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Papers by Crop Breeding

Journal of Crop Breeding, 2024

Background: Alfalfa is the most important leguminous forage that plays a key role in providing fo... more Background: Alfalfa is the most important leguminous forage that plays a key role in providing fodder needed for the production of human protein and dairy products. This plant has high nutritional value with high adaptability to different conditions. Alfalfa is recommended for sustainable agriculture because it has a deep root system and is a perennial plant, hence it can prevent soil erosion. Alfalfa is an excellent source for the biological fixation of air nitrogen. Researchers believe that 65% of the total nitrogen used in agriculture is through biological nitrogen fixation. It is very palatable and effective in the growth of livestock in terms of fodder quality and the optimal amount of energy from plants. In addition to protein, this plant is rich in vitamins, especially A, C, E, and K, as well as mineral compounds such as calcium. The distribution of the types of annual alfalfa at the global level, especially in arid and semi-arid regions, shows their resistance to water shortage and drought conditions. Alfalfa can be used as a successful plant to prevent desertification and the expansion of deserts. Among annual alfalfas, some species can adapt to 80-100 mm of winter rain for improvement and development in dry areas and desert pastures. However, most of Iran is suffering from water shortage, and one of the limitations of breeding for drought stress is the lack of resistance sources among crop genotypes. For this purpose, the evaluation of wild genotypes can be an important step in this direction. Methods: This research was conducted on perennial alfalfa genotypes (one variety) and one-year alfalfa (nine samples) in a factorial experiment (alfalfa genotypes and stress as the first and second factors, respectively) with three replications in a block design. Samples of alfalfa were evaluated in normal and severe stress conditions in the greenhouse of the Faculty of Agricultural Technology, University of Tehran (Abureihan Campus) during 2012-2013. The factorial experiment was conducted based on a randomized complete block design with three replications. The irrigation factor was water deficit stress including irrigation when soil moisture reached 30% of field capacity (severe stress), and the second irrigation level was normal conditions. Cultivation was carried out in May at a temperature of 22 °C, a photoperiod with 16 hours of light, and adequate humidity. Sixty medium plastic pots with an opening diameter of 15 cm, a height of 15 cm, and a capacity of 2 kg were filled with soil. Before planting, the seeds were broken by pulling soft sandpaper on their surfaces and performing stratification, followed by the seed germination test. Light irrigation was done one day before planting. Then, seven seeds were planted in each pot at a depth of 1 cm, and the soil surface was covered with cocopeat to protect soil moisture. The soil of the pots was watered with a sprinkler twice a day until the stress application. After reaching a height of 15 cm, 50% Hoagland's solution was used to feed the plants. After 55 days from the time of planting, the morphological traits, such as stem number, plant height, leaf number, internode number, internode length, leaf area, dry leaf weight, and dry stem weight, were evaluated at the vegetative growth stage. The weight method was used to adjust the soil moisture

Journal of Crop Breeding, 2024

Background: The Production of high-yielding and stable cultivars is the most important objective ... more Background: The Production of high-yielding and stable cultivars is the most important objective of crop breeding programs, including wheat. Wheat is one of the key crops cultivated in Iran. The final yield of each plant is determined by the genotype potential, the environmental effect, and the interaction effect of genotype × environment. Studies on genotype × environment interactions can help determine whether a genotype is stable in performance across a wide range of environments. Various methods (univariate and multivariate methods) have been introduced to evaluate the interaction effect, each of which examines the nature of the interaction effect from a specific point of view. The results of different methods may not be the same, but the best result is obtained when a genotype with different evaluation methods shows similar results in terms of stability. Univariate methods do not provide a complete view of the complex and multidimensional nature of genotype × environment interaction, therefore, the use of multivariate methods is suggested to solve this problem. Among the multivariate methods, genotype × genotype-environment (GGE) biplot methods are more important. Therefore, this study aimed to identify promising and stable top-performing lines of bread wheat for warm and dry climates using the GGE biplot method. Methods: The adaptability and stability of 37 promising bread wheat lines were evaluated in 10 environments, along with three checks (Chamran2, Sarang, and Mehregan). The experiment was conducted using a randomized complete block design with three replications in two cropping seasons (2020-2021 and 2021-2022) at five research stations (Darab, Ahvaz, Dezful, Khorramabad, and Zabol). In the field, each plot was planted with a density of 450 seeds/m 2. Each line was planted in plots with six four-meter lines with 20 cm line spacing. At the end of the growing season, six rows of five-meter spikes from each plot were harvested and threshed by a Wintersteiger combine. The weight of the obtained grains was measured by a digital scale and reported in hectares. Grain yield was determined using combined analyses of variance. The GGE biplot statistical method (genotype effect + genotype × environment interaction) was used to

Journal of Crop Breeding, 2024

Background: One method for selecting high-yielding cultivars is selection based on physiological ... more Background: One method for selecting high-yielding cultivars is selection based on physiological traits. Investigating the seed growth and filling process and its effect on seed weight is among the basic research in breeding programs. The speed and period of grain filling are important traits affecting grain yield in wheat, which are affected by environmental conditions. Selection based on traits such as seed filling speed and period can be a good physiological criterion for cultivar evaluation. This research aimed to evaluate the yield, speed, and period of grain-filling in bread wheat genotypes under end-of-the-season drought stress conditions and to identify superior genotypes. Methods: In this research, 18 bread wheat genotypes along with two control varieties were obtained from the Ardabil Agricultural Research Station and Natural Resources. An experiment was conducted in a completely randomized block design with three replicates in two conditions of full irrigation and drought stress at the end of the season in the Ardabil Agricultural Research Station. In the field, the genotypes were cultivated inside each plot of 4 × 3 m with a distance of 20 cm between lines and a density of 400 seeds/m 2. Genotypes were cultivated in the research station in the fall of 2019. In stress conditions, irrigation was not applied from flowering to seed maturity, while irrigation was carried out three times (early flowering, mid-seed setting, and late seed setting) from flowering to physiological maturity in stress-free conditions. Grain yield traits, grain filling speed, maximum grain dry weight, length of grain filling period, and effective grain filling period were measured in this study. Results: The results of variance analysis for the evaluated traits showed a significant difference between environments and between genotypes in all evaluated traits. The genotype × environment interaction effect was also significant for all mentioned traits. The significance of the difference between genotypes indicates genetic diversity between the studied cultivars. Moreover, the significance of the interaction effect showed that the studied genotypes did not behave the same in two environments without and with stress. The seed-filling rate of all genotypes decreased under drought-stress conditions. The average seed-filling rates were 1.20 and 1.37 mg per day in the stressed and non-stressed environments, respectively. The length of the grain-filling period and the effective grain-filling period decreased with increasing the grain-filling speed. The length of the seed-filling period in the stressed environment was shorter by 2.31 days on average. The effective length and period of seed filling were directly related to the seed dry weight. The average yield of genotypes under stress conditions (594 g/m 2) declined significantly compared to the nonstress environment (768 g/m 2). On average, the length of the seed-filling period in the stressed environment (34.90 days) was shorter than that in the non-stressed environment (37.21 days). The greatest decrease in the effective length of seed filling was observed in genotype 5 (5.30 days). The longest seed-filling periods were recorded for genotypes 14 (41 days) and 12 (40.44 days) in stress conditions, and genotype No. 13 (43.21 days) in non-stress conditions. Genotype 3 showed the shortest seed-filling period in both stress and non-stress conditions. The correlation coefficients showed a negative and significant correlation between the speed and the effective period of seed filling in the stress (r =-0.358**) and non-stress (r =-0.404**) environments. A cluster analysis of the genotypes grouped them into three and four clusters in the stress and nonstress environments, respectively. The heat map of the distribution of genotypes grouped them into three clusters based on the traits studied in the stressful environment. Genotypes 19, 18, 3,

Journal of Crop Breeding, 2024

Conclusion: Based on the findings of this study, the quinoa crop, similar to other salt-tolerant ... more Conclusion: Based on the findings of this study, the quinoa crop, similar to other salt-tolerant plants, employs various strategies (such as ionic balance and alterations in gene expression) to endure saline conditions. The research findings indicate that there was a notable rise in the NHX1 gene expression following the introduction of the sodium ion into the cytosol and receipt of the stress signal. Upon this heightened expression, the plant attempted to chelate sodium ions to mitigate the impact of stress in the vacuole. Additionally, it appears that the plant utilizes the SOS1 gene to initiate an alternative pathway for achieving tolerance and cell stability. This involves releasing sodium ions to the root area, storing them in vacuoles, preventing their buildup in the cytoplasm, and regulating sodium transport over long distances between the roots and leaves. The process also involves the selected loading of sodium ions from the xylem vessels. On the third day, there was a rise in the expression of the CMO gene at the same time as the notable rise of sodium ions in the cytosol, indicating the plant's effort to achieve osmotic equilibrium in the cell by generating glycine-betaine osmolyte and activating the proline synthesis pathway. Alternatively, the plant seeks to preserve the ionic equilibrium by boosting potassium intake and enhancing the stability of the K+/Na+ ratio to mitigate the detrimental impact of stress. Because of inadequate research on this crucial plant, the results of this study can serve as an appropriate blueprint for future research.

Journal of Crop Breeding, 2024

Background: Bread Wheat is the most extensively cultivated wheat and one of the four major crops ... more Background: Bread Wheat is the most extensively cultivated wheat and one of the four major crops in the world that constitutes the principal food of more than 30% of the world population. Biotic and abiotic environmental stressors are major factors limiting plant growth and productivity, which play a significant role in determining the yield and production potential of plants by affecting morphological, physiological, biochemical, and molecular processes. Among the abiotic stresses, the deficiency of micronutrients in the soil is important. Micronutrients regulate food metabolism in humans, and their deficiency endangers human health. Iron and zinc are essential micronutrients for human health and cofactors of many vital enzymes involved in many human metabolic processes. In plants, iron is the most required element among all micronutrients. It is a part of the catalytic group of many oxidation and reduction enzymes and is required for chlorophyll synthesis. To facilitate the adequate uptake and prevent excessive absorption of iron, plants have developed a balanced network to regulate the uptake, use, and storage of ions. In fact, such adjustment processes depend on genes that regulate ion homeostasis in plants. Due to the existence of a large allohexaploid genome and technical challenges in wheat transformation, few genes involved in iron and zinc uptake, transfer, and storage have been characterized functionally. Considering the important role of ZIP proteins in iron uptake efficiency, investigating the expression of the ZIP genes in Fe-efficient andinefficient bread wheat cultivars can be effective in improving Fe-efficient cultivars in this valuable crop. Therefore, this research aimed to evaluate the expression of ZIP3, ZIP6, and ZIP7 genes in the leaves and roots of two Fe-efficient and-inefficient bread wheat cultivars at different growth stages under iron deficiency stress. Methods: This research was carried out in a completely randomized design (CRD) based on a factorial experiment with three replications in the research greenhouse of the Faculty of Agriculture, Urmia University. The first factor was two Fe-efficient (Pishtaz) and-inefficient (Flat) bread wheat cultivars, the second factor was two soil iron levels (iron deficiency and sufficiency, respectively, 1.4 and 10 mg/kg of soil), and the third factor was two sampling stages (vegetative and reproductive, respectively, one month after planting and 30% heading). To evaluate the expression of genes, the roots and leaves of the plants were sampled at each growth stage. The seeds were obtained from the Iranian Seed and Plant Improvement Institute, disinfected with 1% hydrogen peroxide, and planted at a depth of 4 cm in the soil. The plants were irrigated using distilled water to the extent of field capacity during the growing period. Results: The results of variance analysis of the relative expression of all three studied genes showed that the interaction effect of cultivar × organ × sampling stage was significant at the probability level of 1%. The comparison of the means for the cultivar × organ × sampling stage interaction effect revealed the highest ZIP3 expression in the roots of the Fe-efficient cultivar (Pishtaz) in the vegetative and reproductive stages. The relative expression of this gene was higher in the roots of the Fe-inefficient cultivar (Falat) than that of the Fe-efficient cultivar (Pishtaz). However, the Fe-inefficient cultivar (Falat) showed the highest relative expression increase in the leaf in both reproductive and vegetative stages, but the difference in the gene

Journal of Crop Breeding, 2024

Background: In arid and semi-arid regions, biotic and abiotic stresses can directly or indirectly... more Background: In arid and semi-arid regions, biotic and abiotic stresses can directly or indirectly lead to restrictions and decreased growth of different plants. In these areas, salinity stress is one of the major challenges facing agriculture and crop production that causes huge damage to crop yields annually. The amount of salinity in the soil results in plant growth limitation, and increased soil salinity disrupts water and essential nutrient absorption for the plant and reduces plant growth, which can then lead to plant death. Reduced root growth and development, decreased nutrient absorption, increased likelihood of allergies to diseases and pests, decreased yield, and final product quality (e.g., nutrient deficiency), and increased toxic elements, are among the negative effects of salinity on plants. Various factors are involved in the creation of salinity, the most important of which can be climate change, source rock weathering, improper irrigation, drought, excessive consumption of fertilizers, and reduced seawater levels. Following climate change, these damages are on the rise every year. Due to the increase in population growth, demand for food production is increasing day by day. Wheat is known as the major grain in the supply of nutritional needs in the world, hence its sustainable production is of paramount importance. Salinity is recognized as an important factor in reducing wheat yield, and it may increase the accumulation of harmful salts in the plant tissue, which can lead to physiological damage and decreased plant growth. The effects of soil salinity vary depending on the amount of salinity, the type of salinity, and the type of wheat. One way to prevent the negative effects of salinity is to use salinity-resistant wheat cultivars. The range of diversity in relation to salt stress tolerance in different plants, especially the wheat plant, depends on various factors such as plant genotype, duration of stress, and plant growth stage. The seedling stage in wheat is one of the important stages regarding tolerance to salt stress. This study aims to investigate the response of spring wheat cultivars in the seedling stage to salinity stress. Methods: In the present study, the reaction of 64 Iranian spring wheat genotypes at the seedling stage under normal conditions and 12 dS/m salinity stress was investigated in two replications in a simple lattice design at the research greenhouse of the Faculty of Agriculture, Urmia University in 2021-2022. In this study, in the four-leaf stage, salinity stress was applied gradually for two days. The measured traits were chlorophyll (SPAD), canopy temperature, shoot length (SL), root length (RL), seedling length (PL), shoot potassium content (KS)), root potassium content (KR), shoot sodium content (NaS), root sodium content (NaR), shoot potassium to sodium ratio (KNaS), root potassium to sodium ratio (KNaR), root volume (RV), leaf area index (LAI), radicle fresh weight (FWR), radicle dry weight (DWR), relative leaf water content (RWC), shoot fresh weight (FWS), shoot dry weight (DWS), seedling fresh weight (FWP), weight dry matter of seedlings (DWP). The data of the studied traits were obtained in a random complete block design. PROC GLM was used for the analysis of variance (ANOVA) in SAS 9.4 software. The correlation was examined using PROC CORR and decomposition into factors using PROC FACTOR. The figures were grouped using the gplots software package and the biplot diagram was drawn with the factoextra software package in the R 4.1 environment. The MANOVA statement in PROC GLM was used in SAS 9.4 software for multivariate variance analysis. Results: Based on the results of ANOVA, statistically significant differences were observed between the tested cultivars based on the traits studied in the seedling stage, including FWP, DWP, FWR, DWR, FWS, RWS, and (PL). In both normal and salt stress conditions, DWP showed the most significant correlation with FWP, DWS, and DWR. Under the salinity stress conditions, FWS was significantly correlated with DWS, FWP, and DWP. Based on factor

Journal of Crop Breeding, 2024

Background: Lentil (Lens culinaris Medik) is a cool season seed legume and a good source of nutri... more Background: Lentil (Lens culinaris Medik) is a cool season seed legume and a good source of nutrients needed by humans, including protein, carbohydrates, vitamins, and minerals. The production of high-yielding and high-plant-height varieties is one of the lentil improvement goals. For this purpose, it is necessary to collect and evaluate germplasm as a base population, along with identifying and utilizing lines with high potential and other desirable traits. The environment has a significant effect on the crop production of this plant. Therefore, direct selection is important for seed yield. Since seed yield depends on the yield components, the yield and its components must be regarded as a group at the selection time to improve the yield. To properly increase yield and economic efficiency, we need to collect desirable lines with desirable genes and transfer these genes to cultivated lines to produce desirable cultivars. Consequently, sufficient information is necessary on accessible genetic materials, which is possible by evaluating different traits. Methods: To assess the model of the simultaneous effect of traits on the lentil seed yield for determining the selection procedure in native lentil lines of Zanjan province, an experiment was conducted in the research farm of the Faculty of Agriculture, Zanjan University, during two cropping years 2017-2018 and 2018-2019. In both years of the experiment, improved cultivars, such as Kimia, Sabz Kohin, Gachsaran, Maragheh, and Bilehsavar, were used as control cultivars. The first-year experiment was conducted in an augmented design based on a randomized complete block design with 200 lines. Each experimental unit included a 1-m row. The distance between the rows was 25 cm, the distance between plants in a row was 5 cm, and the planting depth was 5 cm. Two rows of Kohin-Sabz lentils were planted as margins at the beginning and end of each block. Due to obtaining a sufficient amount of seeds from the first year, the second-year experiment was carried out as a simple lattice design with two replications and larger experimental units for the lines selected from the first year. Each experimental unit included two 1-m lines. The distance between the rows, the distance between plants in a row, and the planting depth were similar to the first-year experiment. Two rows of Kuhin green lentils were planted as margins at the beginning and end of each incomplete block. The measured traits included phenological and morphological traits, yield, and yield components per plant and unit area. Results: Among the studied traits, the highest coefficient of variation was obtained for the number of seeds, biomass, straw yield, and seed yield. The coefficient of correlation showed that the number of seeds and seed yield were positively and significantly correlated with phenological traits, such as the podding period, physiological maturity, and seed-filing period, as well as morphological traits such as plant height and first branching height, respectively. A positive and significant correlation was observed between the number of seeds and seed yield with the number of pods per plant and biomass per plant. In regression analysis by the stepwise method, plant height was the first trait entered into the model, which could explain 46.8% of the variation related to seed yield per plant. Then, the number of seeds per plant, 1000-seed weight (TSW), straw yield per plant, and the seed-filling period were entered into the model, respectively, which could totally explain 67.5% of the variation related to seed yield per plant. The results of the path analysis showed that the number of seeds per plant had the most considerable direct and positive effect on seed

Journal of Crop Breeding, 2024

Background: Lentil (Lens culinaris Medik.) is one of the main food legume crops in Iran, where it... more Background: Lentil (Lens culinaris Medik.) is one of the main food legume crops in Iran, where it is grown as a rainfed crop in spring in cold regions. One of the obstacles of spring cultivation in cold regions is drought stress exposure at the end of the growing season in the late cultivation date, which dramatically increases null pods and decreases seed yield. Until introducing autumn cultivation, specific, and cold-tolerant lentil varieties, the only solution for this problem is to find ways to deal with the damage of drought stress. Nanotechnology serves as a precursor of the new industrial revolution that has the potential to bring alteration in agricultural production. Nanoparticles (NPs) have been applied for enhancing seed germination, growth, physiology, productivity, and quality traits of various crops under normal or stressful conditions. Therefore, to reduce the negative effect of drought stress at dryland conditions in late cultivations, the effect of ZnSO4 and Fe2O3 NPs at 0.5% and 1% were studied on the agronomic, physiologic, root traits, and antioxidant system of lentils in the cold region. Methods: A field study was carried out at the Dryland Agricultural Research Center (DARI) in Maragheh during the 2019-2020 growing season. Experiments were conducted in rainfed conditions using a complete block design with three replications. Treatments were no spray, 0.5% nano ZnSO4, 1% nano ZnSO4, 0.5% ZnSO4, 1% ZnSO4, 0.5% nano Fe2O3, 1% nano Fe2O3, 0.5% Fe2O3, and 1% Fe2O3. Treatments were applied at two stages (10 days after the plant first establishment and 50% of flowering) in the early morning and not on windy days. The Bilesavar variety, which is suitable for spring cultivation in cold regions, was used in this experiment. Plant height, relative water content (RWC), cell membrane stability (CMS), canopy temperature, and the normalized difference in the vegetative index (NDVI) were recorded during the growing season. The seed yield and 100 seed weight (HSW) were calculated after harvesting. The activity of ascorbate peroxidase (ASP), catalase (CAT), glutathione peroxidase (GPX), superoxide dismutase (SOD), peroxidase (POX), and the contents of proline, chlorophyll a, chlorophyll b, and carotenoids were calculated in gathered leaf samples during the growing season. Results: Differences between treatments were significant for RWC, CMS, canopy temperature, NDVI, and seed yield at 1%, and for HSW at 0.5%. The highest seed weight was observed in using nano Fe2O3 0.5%, and the lowest belonged to no spray treatment. The lowest RWC, CMS, and the highest canopy temperature were recorded in no spray treatment. Analysis of variance results showed that differences between treatments for all biochemical traits were significant at the 1% level. Chlorophylls a and b contents increased using NPs, and the highest level belonged to 1% nano ZnSO4 treatment and as expected the lowest calculated in no spray treatments. The highest carotenoids, and the activities CAT, ASP, GPX, and SOD were observed in 1% nano ZnSO4 treatment. The lowest activity of these enzymes as well as the highest H2O2, proline, and malondialdehyde (MDA) belonged to no spray treatment. According to the results, seed yield was significantly correlated with CAT (0.

Journal of Crop Breeding, 2024

Background: About 30% of the world's sugar needs are provided by sugar beet and sugar cane. Many ... more Background: About 30% of the world's sugar needs are provided by sugar beet and sugar cane. Many biotic factors, such as pests, diseases, and weeds, decrease production and damage sugar beet fields. To bring sugar beet production to its real potential and maintain it at this level, it is necessary to identify biotic stress-causing factors, determine their individual role in reducing the yield, and investigate their management and control methods. One of the pests of sugar beet is the root aphid that settles on the secondary roots and causes dwarfism and wilting of the plants by feeding on plant sap. It also causes a decrease in root weight and a 30-36% decrease in sugar content. Due to the special conditions of the aphid's life under the soil, the effect of the aphid's white wax secretions on soil non-wetting by the poison solution, and the lack of a suitable systemic poison, the use of chemical poisons in the form of soil-water is not recommended in controlling this pest. Therefore, the most effective method for managing this pest in sugar beet fields is to use resistant and tolerant cultivars. Therefore, this research aimed to evaluate the resistance of domestic and foreign cultivars to this type of aphid. This study also investigates the effect of this pest on their quantitative and qualitative yields to use them or their ancestors in future breeding programs to produce resistant cultivars. Methods: The resistance to root aphid of eight sugar beet cultivars (Asia, Arta, Dena, Shokoofa, biopolymerized Shokoofa, Nika, Palma, and BTS505) and the effect of this pest on their quantitative and qualitative yields were evaluated in a pilot experiment based on a randomized complete block design with four replications in the West Azarbaijan Agricultural and Natural Resources Research Center, agricultural education center of Miandoab city, in 2023 crop season. To this aim, sugar beet root aphid was sampled by harvesting 20 sugar beet roots (four replicates per cultivar) in the middle of September. The samples were grouped into four resistant, semiresistant (tolerant), sensitive, and very sensitive groups based on the percentage of sugar beet roots infected with aphids. Traits related to quantitative and qualitative yields were also measured after harvesting. Results: The results of the analysis of variance showed that the effect of the cultivar was significant on all measured traits (p ≥ 0.01). The highest and lowest values of the genotypic and phenotypic coefficients of variation belonged to the percentage of aphid-infected roots (46.52% and 46.73%, respectively) and the sugar extraction coefficient (4.55% and 4.69%, respectively). Based on the results from mean comparisons for the cultivars, the highest and lowest values of the root yield trait was measured in BTS505 and Palma foreign cultivars with 82.35 and 62.81 t.ha-1 , respectively, which were placed in two statistical groups. However, the average root yield of the Palma cultivar with the lowest root yield was not significantly different from the Shokoofa cultivar (64.41 t.ha-1). The highest sugar content trait belonged to the BTS505 foreign cultivar (16.86%), and the lowest values were obtained for the Palma foreign cultivar and the Shokoofa domestic cultivar (12.65 and 13.01%, respectively). No significant differences were observed between the domestic and foreign cultivars in the averages of the root yield trait (69.56 and 72.58 t.ha-1 , respectively) and sugar content (14.25 and 14.75%, respectively). This indicates the genetic progress of the newly introduced domestic hybrid cultivars in terms of these two important traits that influence the final yield of sugar. In terms of the percentage of aphid-infected roots, the

Journal of Crop Breeding, 2024

Background: Chickpea (Cicer arietinum L.) is a legume grown in cool season areas. It is one of th... more Background: Chickpea (Cicer arietinum L.) is a legume grown in cool season areas. It is one of the main sources of protein and energy and plays a major role in improving soil fertility. Peas are divided into two classes, Desi and Kabali. The Desi seed is smaller, wrinkled, and darker while Kabli has a lighter, whiter seed color, larger seed size, and smooth surface. The chickpea yield is 1199 kg per hectare in America, 1261 kg per hectare in India, and 409 kg per hectare in Iran. Until 2005, this plant was called an orphan plant due to the insufficient genetic resources in chickpeas, but the plant was known as a plant with a rich genomic resource after many efforts at national and international levels. Further studies on chickpea genetic diversity are important to improve the yield. Chickpeas have plenty of diversity in different geographical regions, and the genetic pattern and the amount of variation within and between these populations should be known to progress breeding programs and effectively use these germplasm collections. The evaluation of genotypes faces two key challenges. The first is the genotype-environment interaction, and the second is the interaction between the studied traits. This study aimed to investigate the genetic diversity in the Desi chickpea germplasm under autumn cultivation conditions, analyze the relationships of morphological-agronomical traits, and select superior genotypes in terms of all morphologicalagronomical traits. Methods: This study was conducted on 416 genotypes, including 335 landrace of Iran, 1 ICARDA genotype, and 78 ICRISAT genotypes, along with two checks named Kaka and Pirouz cultivars in the experimental farm of the Dryland Agricultural Research Institute (Kermanshah). The cultivars were evaluated in terms of morphological-agronomic traits, including the number of days to flowering, the number of main branches, the number of secondary branches, the number of pods per plant, plant height, the end number of days to maturity, seed yield, and 100-seed weight (HSW). The experiment was conducted during 2020-2021 under autumn sowing conditions and as an augmentation based on a randomized complete block design with nine blocks. The variance, heritability, and genetic advance were analyzed with the R software packages (augmentedRCBD). The R software package (metan) and (GGEBiplotGUI) were used for the biplot analysis of the genotype by trait. Data were grouped using the K-mean algorithm, single method, and Euclidean distance with R software. The R software package (NbClust) was used to calculate the number of appropriate groups resulting from the cluster analysis. Using the R software package (metan) with the selection index (MGIDI), the top genotypes were ranked based on several traits. Results: The results of the analysis of variance were significant for the number of days to maturity, HSW, and plant height. The highest and the lowest coefficients of variation belonged to the number of secondary branches and days to maturity, respectively. The plant height and HSW traits had high values of heritability and genetic advancement. According to the results of the genotype by trait biplot, genotypes 148, 327, 391, and 277 were in the best conditions in terms of HSW, days to maturity, plant height, and days to flowering. Genotypes 6, 400, 18, 42, 26, 168, 15, and 2 were in the best conditions for the number of pods per plant, seed yield, the number of main branches, and the number of secondary branches per plant. According to the findings of the genotype by trait biplot, most of the selected genotypes were from the landrace of the Iranian chickpea. Clustering was performed using the K-means method, which divided the genotypes into two groups. In the second group, genotypes 6, 18, 148, 327, and 91 had more distances (according

Journal of Crop Breeding, 2024

Background: Alfalfa is one of the key fodder plants due to its species diversity and high stresst... more Background: Alfalfa is one of the key fodder plants due to its species diversity and high stresstolerance range. In addition to producing significant palatable fodder, this plant stabilizes air nitrogen through symbiosis with rhizobium and causes soil fertility in addition to meeting its own needs. For fodder production in the hot and dry region of Sistan as the hub of animal husbandry in the province, it is inevitable to investigate and introduce high-yielding alfalfa cultivars. Therefore, the present research aimed to evaluate tropical alfalfa cultivars and identify high-yielding and more compatible cultivars in terms of yield production and selection of stands with suitable potential for selection. Methods: The phenological, morphological, and functional traits of 10 tropical alfalfa genotypes (Zabol local purified alfalfa, Zabol local mass, Baghdadi, two Afghani masses, Nikshahri, Omid, and lines 473, 472, and 471) were investigated in the Zahak Agricultural and Natural Resources Research Station, located 20 km from Zabol city. An experiment was conducted in a statistical design of randomized complete blocks with three replications during 2017-2018. The bed preparation, including plowing, disk, and leveling, was operated exactly the same for the replications. The distance between the plots in each block was 75 cm, and the distance between the blocks in each replication was 1 m. After preparing the bed on November 15, 2016, furrows were created at a distance of 30 cm (four lines of 6 m) in the plots, and seeds with 95-100% germination capacity were planted at a rate of 15 kg per hectare. Seeds were sown in a row manually by opening grooves to a depth of 1 cm using the method of Hiramkari. During the experiment, the operation consisted of irrigation every 15 days in winter, spring, and summer (once a week) according to the needs. Weeds were mechanically weeded in the early stages of growth. In each year, eight plants were harvested at the 20% flowering stage. Days to greening, days to flowering, plant height, leaf-to-stem percentage, stem diameter, stem number, dry matter percentage, and wet and dry fodder yields were the traits measured during the experiment. At the end of the experiment, data on the fodder yield and morphological and phenological traits of alfalfa cultivars were analyzed using MSTAT-C software. The correlation was calculated using SPSS 16 software. Analysis into principal components and the biplot were done using the Past software. The means of traits were compared with Duncan's test at the probability level of 5%.

Journal of Crop Breeding, 2024

Background: Wheat is the key crop in many parts of the world that has the largest cultivated area... more Background: Wheat is the key crop in many parts of the world that has the largest cultivated area. As much as 30% of all grains produced in the country belong to wheat, which is known as the main food of half of the world's people. At the same time, environmental stresses, including biotic stresses, have been one of the most important factors in reducing wheat yield in recent years. Powdery mildew (Blumeria graminis f.sp. tritici) is one of the important diseases of wheat that causes great losses to wheat production every year. On the other hand, the resistance of resistant wheat genotypes is not constant over time, and the resistance of almost all resistance genes commonly used in the world has been broken by new pathogenic strains of powdery mildew. This is because research has shown that the high pressure imposed by resistance genes on disease-causing populations has caused the rapid evolution of new pathogenic races, resulting in the loss of resistance. For this reason, one of the most effective and logical methods of controlling this disease, which is most compatible with the environment and sustainable agriculture, is the identification and production of resistant cultivars. Methods: In the present study, 32 different bread wheat genotypes (Triticum aestivum L.

Journal of Crop Breeding, 2024

Background: As one of the most important cereals, bread wheat is an essential part of food securi... more Background: As one of the most important cereals, bread wheat is an essential part of food security in the world, which supplies one-fifth of the total calories of the world population. Nowadays, the yield of wheat has been affected by climate change-driven drought as one of the most important abiotic stresses that has become an important threat to food security in the world. Root and stomatal traits are especially important in breeding plants to withstand drought stress. Stomata play a key role in controlling carbon dioxide uptake and water loss through transpiration. Therefore, stomatal characteristics are used as indicators of water status and plant growth, especially in drought stress conditions. Having a wide range of physiological and morphological characteristics, roots play an essential role in absorbing water and nutrients. They are also the first organ that sends signals to control the stomata in response to dryness. Therefore, the difference in the structure of the root system can cause the difference between the performance in different cultivars. This study was conducted to investigate stomatal characteristics and their relationship with the root system and plant performance in 24 bread wheat lines and cultivars. Methods: To investigate the relationship between stomatal dimensions and density with the root system, an experiment was conducted on 24 bread wheat genotypes in the form of a randomized complete block design with three replications in the rainfed conditions of the research farm at Zanjan University Faculty of Agriculture in the crop year 2018-2019. In this experiment, PVC pipes were used to study the root system. Twelve seeds were planted in each tube, which were thinned to seven after germination. In each experimental unit, there were two tubes for each genotype, one of which was used to evaluate traits and final yield, and the second tube was used for root studies. Stomatal traits, including the length and width of stomata and number of stomata per unit area, root traits including root length, root diameter, root volume, root surface, and root biomass, and seed yield were measured in the end. The resulting data from the measured traits were analyzed in the form of a randomized complete block design, and the averages were compared using the LSD method. The data were analyzed using multivariate statistical analyses, including regression analysis, path analysis, and factor analysis, and cluster analysis was used to group genotypes. Statistical calculations were done using SAS 9.0 and SPSS 21 software. Results: The results of analysis of variance and mean comparison showed high variability among genotypes for all measured traits. The results of the mean comparison of genotypes showed that genotypes 2, 5, 8, and 16 had the highest yield, and genotype 23 had the lowest yield among the examined genotypes. The highest number of stomata on the upper and lower leaf surfaces belonged to genotypes 5 and 2. In terms of root traits, the highest diameter, volume, length, root surface, and root dry weight at a depth of 0-25 cm were recorded for genotypes 2, 3, 18, and 5, respectively. There was a high and significant correlation between the

Journal of Crop Breeding, 2024

Introduction and Objective: Salinity stress is one of the most important limitations of rice cult... more Introduction and Objective: Salinity stress is one of the most important limitations of rice cultivation worldwide. On the other hand, the use of physical and chemical mutagens can be very important not only to the development and combination of new genes or alleles with agricultural importance but also to introduce genotypes more adaptable and stable to adverse weather and soil conditions. For this reason, with the development and progress of rice varieties that are tolerant and adapted to salinity, it is possible to increase the sustainable production of this stable food. Therefore, the present study was conducted with the aim of investigating the response of the tenth generation (M10) of rice mutants to salinity stress in the reproductive stage using agronomic and biochemical characteristics. Material and Methods: In this research, 13 mutant lines of Seng-e-Tarem, Hashemi and Khazar cultivars using gamma ray irradiation from Cobalt 60 which have been previously identified as tolerant lines in molecular studies were used along with the tolerant cultivars of Nonabukra and Deylamani and sensitive cultivars of IR29 and Sepidrood. The genotypes were exposed to three levels of salinity (0, 4 and 8 dS/m) from the source of sodium chloride. A factorial experiment based a randomized complete block design (RCBD) and a factorial split based a RCBD with three replicates were used to evaluate agronomic traits along with yield and biochemical traits, respectively. The measured parameters were tillers number (TN), the number of filled (NFG) and unfilled grains (NUG), 1000 grains weight (TGW), plant height (PH), Days to 50% of flowering (DTF) and the paddy yield (PY), and for the biochemical traits, the activity of catalase (CAT) and superoxide dismutase (SOD), protein (PN), proline (PR) and malondialdehyde (MDA) contents and electrolyte leakage (EL) percentage. Results: The results of the variance analysis showed that the effect of salinity and genotype and their interactions were significant for all the measured traits. A wide range of genetic diversity was observed among the genotypes for the agronomic and biochemical traits. Among the traits, PY was identified as the best and the most indicative trait to classify the tolerant genotype under salt stress conditions. Among the investigated mutants at different levels of salinity, the highest PY was recorded in MP6, MP10 and Deylamani genotypes, respectively. PY value in MP10 mutant at the salinity level of 8 dS/m was closed to Deylamani variety (tolerant check). With the increase of salinity from zero to 8 dS/m, the measured traits adversely affected. The cluster analysis diagram of studied genotypes based on agronomic traits and PY at a salinity level of 4 dS/m classified the genotypes into three separate groups. The genotypes MP2, MP3, MP4, MP9, and MP10 were grouped in the second group, in which Deylamani cultivar was also present as a tolerant check. The cluster analysis diagram of agronomic traits and PY at the salinity stress level of 8 dS/m divided the genotypes into four different groups. In the third group, two genotypes of MP9 and MP10 were included with Tarem Deylamani variety (tolerant check). The correlation coefficient between agronomic traits in 8 dS/m of salt conditions showed that PY had a positive and significant correlation with PH (r=0.51), the NFG (r=0.88) and TGW (r=0.63). Also, there is a negative correlation between DTF with PH (r=-0.70) and NFG (r=-0.62) and a positive and significant correlation with TN (r=0.60). Biplot analysis divided the studied lines into four groups based on agronomic traits at a salinity level of 4 dS/m. The first group includes six mutant lines as very sensitive group, the second group includes two mutant lines as sensitive group, the third group with three genotypes including lines MP9, MP10 and Tarem Deylamani variety (tolerant check) as tolerant group and the fourth group with six genotypes included lines MP11, MP12, MP13 and Nonabukra variety (international tolerant check) as well as Sepidrood and IR29 varieties as high salt tolerant group. Also, biplot analysis based on agronomic traits at a salinity level of 8 dS/m divided the studied lines into four groups. The first group consisted three mutant lines as very sensitive group, the second group included six lines as sensitive group, the third group involved five genotypes including MP11 and MP13 lines and Nonabukra varieties (tolerant check), Sepidrood and IR29 as the tolerant group and the fourth group with three genotypes included MP9 and MP10 lines and Tarem Deylamani variety (native tolerant check) as high salt tolerant group. For biochemical traits at 8 dS/m of salt stress, the highest amount of SOD was recorded in Deylamani cultivar (tolerant check), PN for MP2 mutant, PR for MP3 mutant, and the lowest amount of EL and MDA was recorded for MP2 and MP10 mutants, respectively. Conclusion: In general, PY of MP10 mutant line in salt stress conditions was closed to Deylamani as a native salt tolerant cultivar, therefore could be introduced as a superior line for further research in saline conditions.

Journal of Crop Breeding, 2024

Introduction and Objective: Black rust is one of the important fungal diseases that widely affect... more Introduction and Objective: Black rust is one of the important fungal diseases that widely affects the quantity and quality of wheat in many regions of the world. The damages caused by black rust disease can be more than other pathogens in wheat and its importance is such that millions of hectares of healthy fields with high production potential can be destroyed in less time. Destroy it completely in one month. Resistance is one of the genetic characteristics of the host that plant breeders use to produce cultivars. Lines that are recognized as resistant in a survey can be used as a source of resistance in another breeding program. Genetic resistance reduces or eliminates the consumption of chemical poisons, and as a result, it is considered as the most economical and healthiest method of combating plant diseases. Accordingly, in order to statistically investigate some physiological markers related to resistance to black rust disease, 24 bread wheat genotypes including 8 cultivars and 16 promising lines were studied. In this study, two varieties MV-17 (disease-resistant variety) and Morocco (disease-susceptible variety) were selected as controls in this study due to their different behavior in resistance to wheat black rust. Material and Methods: This experiment was carried out in 2019 in the greenhouse of the Research Institute of Plant Breeding and Seed Preparation under the conditions of infection and non-infection with the native race TKTTF of wheat black rust disease and in the form of a randomized complete block design with four replications. Physiological traits including relative leaf water content (RWC), cell membrane stability (MP), electrical conductivity (EC), chlorophyll content (SPAD) and chlorophyll fluorescence were measured and recorded. Results: At the probability level of 1%, a significant difference between genotypes was observed and the interaction effect of disease x genotype was significant for all traits, which indicates the non-homogeneous difference of genotypes for the studied traits in two conditions of infection and non-infection. Also, for all measured traits, there was a significant difference between two different levels of disease infection, which shows the effect of the black rust pathogen on the relative content of leaves, membrane permeability, electrical conductivity, chlorophyll concentration, primary fluorescence, fluorescence It has maximum, variable fluorescence and photochemical efficiency of photosystem II. The results showed that pathogen contamination increases the relative water content, chlorophyll concentration, membrane permeability, initial fluorescence, maximum fluorescence, variable fluorescence, photochemical efficiency of photosystem II and decrease in electrical conductivity. Based on all studied physiological traits of genotypes MV-17, C-98-17, C-98-11, C-98-5, C-98-12, C-98-18, C-98-16, C-98-3 and CD-94-9 were identified as the genotypes that showed more resistance to the disease agent. There was a high correlation between initial fluorescence, maximum fluorescence, variable fluorescence, photochemical efficiency of photosystem II, membrane permeability and electrical conductivity in response to stem rust. Based on Ward's cluster analysis and detection function analysis, the genotypes were divided into four separate groups in the conditions of infection and non-infection with black rust. They were placed in a group. While, in the condition of no disease contamination, 6, 9, 4 and 5 genotypes were clustered in four separate groups, respectively. Conclusion: This study showed the effect of East Azerbaijan stem rust TKTTF race on the physiological traits of winter cultivars and lines of wheat. This race caused changes in the studied physiological traits in both experimental conditions, from this output it can be concluded that the resistant lines are more resistant to the disease than the commercial variety and are recommended as selected lines in breeding programs should be used. It is worth mentioning that according to the results of the grouping of genotypes and also the placement of valuable genotypes in terms of relative water content traits, membrane permeability index, chlorophyll content, initial fluorescence, maximum fluorescence, variable fluorescence, and photochemical efficiency. Photosystem II and electrical conductivity in the first and second groups in the conditions of disease infection and non-infection, it was concluded that the results of cluster analysis had a good relationship with the results of variance analysis and comparing the average of the studied traits. The results showed that the physiological traits measured in response to black rust disease have diversity. Therefore, possible genotypes with resistance to this pathogen can be identified by using the changes of these traits. Also, considering the relationship between the results obtained from the evaluation of physiological and pathological traits, the possibility of using physiological traits as indicators related to resistance to wheat black rust disease was benefited. In other words, the physiological indicators used were able to detect the existence of diversity and response to resistance to black rust disease and they can be used as physiological indicators related to resistance to black rust disease of wheat. Examining different traits in different environmental conditions has shown that the way the genotypes act and respond to the pathogen changes with the change of environmental conditions. For this purpose, these studies should be carried out in several years and in different environments. It is also recommended to carry out the above test using agricultural traits at the stage of the sorghum plant as well as biochemical traits related to the disease.

Journal of Crop Breeding, 2024

Introduction and Objective: The genetic diversity of plant species and their relationship with wi... more Introduction and Objective: The genetic diversity of plant species and their relationship with wild species is very important to improve the yield of crops..The first step in the improvement of medicinal plants is to identify and collect endemic genotypes.Endemic genotypes are very important in the selection of cultivars due to their adaptability to the climate of the region. Mentha longifolia is one of the important endemic medicinal plants of Iran, which is used in various pharmaceutical, food and cosmetic industries. Essential oil, phenolic compounds, flavonoids and other compounds such as steroids and ceramides are important chemical compounds in oregano plant. In this study, morphological diversity, essential oil and antioxidant activity of 20 Mentha longifolia genotypes in West and East Azerbaijan provinces were investigated. The aim of this research, on the one hand, is to know the potential and range of diversity of Menta longifolia genotypes in its natural habitats in West Azarbaijan and East Azarbaijan provinces. On the other hand, the introduction of regions with superior genotypes in terms of these traits is for use in breeding programs. Material and Methods: The collection of plant samples from some areas of two northwestern provinces of Iran (West Azerbaijan and East Azerbaijan) was done in the spring of 2022. In order to evaluate the morphological traits of the plant in the flowering season, 11 quantitative traits of the plant including plant height, inflorescence length, crown diameterstem diameter, internode length, leaf length, leaf width, number of leaves, number of inflorescences, fresh weight, dry weight and the number of sub-branches were evaluated. After drying the plant samples, essential oil extraction was done using a clonger, and the essential oil samples were transferred to Urmia University Jihad to identify compounds by gas chromatography. Extraction of plant samples was done by ultrasonic method. Antioxidant activity was evaluated by DPPH method. All the obtained data were analyzed with three repetitions and based on a completely random design using SPSS software. LSD test was used to compare the mean data. Data clustering was done based on Ward's method and Euclidean distance square measure. Principal component analysis was performed on the data .Also, in this study, correlation between studied traits was done by R software. Results: The results of analysis of variance showed that the genotypes collected from different regions have significant differences in terms of plant height, inflorescence length, crown diameterstem diameter, internode length, leaf length, leaf width, number of leaves, number of inflorescences, fresh weight, dry weight and the number of sub-branches are investigated (P < 0.01). The results of the analysis of the percentage and chemical composition of the essential oil showed that the type of genotype had a significant effect on the amount of these compounds in different genotypes of Mentha longifolia (P < 0.01). Among the studied genotypes, the highest percentage of essential oil and the amount of Trans-Caryophyllene and Germacrene D compounds were found in G18 of Iranq region of Tabriz, also the highest amount of Alpha-Terpineol and Spathulenol was found in G16 of Aghajari region of Maragheh. Also, there was a significant difference between different genotypes of mint in terms of antioxidant activity. The maximum amount of antioxidant activity (80.81%) was observed in G3 of Hachesu area in Shahindej. Based on Ward's cluster analysis, the genotypes were divided into three main groups. G1 alone was placed in a separate group due to the high content of Spathulenol and high antioxidant activity. The second group, which includes most of the genotypes (G2,

Journal of Crop Breeding, 2024

Introduction and Objective: Maize (Zea mays L.) is the third most important cereal after wheat an... more Introduction and Objective: Maize (Zea mays L.) is the third most important cereal after wheat and rice, which accounts for 26% of total cereal cultivated area and 37% of their production. Maize is a valuable raw material for extracting oil, starch, alcohol, glucose, plastic, lactic acid, acetic acid, acetone and paint, and it is possible to made paper, cardboard, and nitrocellulose from its stalks. As an important nutrient, phosphorus plays important role in energy transfer, photosynthetic oxidation-reduction reactions, as well as in biochemical compounds including nucleic acids, structural proteins, enzymes, and signal transmission. Due to the predominance of calcareous soils with high pH in arid and semi-arid agricultural climates, the amount of available phosphorus is limited. In order to increase available phosphorus for plants, large amounts of phosphorus chemical fertilizers are needed regularly. However, a large amount of phosphorus in fertilizers may be converted to insoluble phosphate, immediately by reaction with calcium in the soil after its application. On the other hand, indiscriminate use of phosphorus chemical fertilizers leads to many environmental problems such as surface runoff of phosphorus, eutrophication of aquatic ecosystems, reduction of biodiversity and abnormal changes in soil salt concentration and pH. Breeding cultivars that absorb phosphate or phosphorus more efficiently is one of the solutions to deal with the stress of phosphorus deficiency as a trait with low heredity. The use of selection indices can be an effective method for the indirect selection of traits with complex genetics. Material and Methods: 93 maize genotypes prepared from different research centers were evaluated in terms of agromorphological traits under normal and phosphorus deficit conditions using completely randomized design with three replications in the crop year 2016-2017 in an open area conditions. For this purpose, after analyzing the soil of different regions, soil with low phosphorus content (7.240 mg/kg) was selected and the pots (15 kg) were filled with soil and sand in a ratio of two to one. Usable soil phosphorus was determined by the Olsen method in the soil science laboratory of Urmia University. In both optimal and phosphorus deficit conditions, soil was strengthened with nitrogen fertilizers (in the amount of 9 g/pot (during three stages during the growth period)), potassium sulfate (in the amount of 13.5 g/pot), Sequestrin (1.5 g /pot), manganese sulfate (0.225 g/pot), zinc sulfate (0.99 g/pot), copper sulfate (0.3 g/pot) and boric acid (0.21 g/pot). In optimal conditions, phosphorus fertilizer in the form of triple superphosphate was added to each pot in the amount of 6 g/pot. Phosphorous fertilizer was not added to the soil in the phosphorus deficit conditions. With the beginning of the tasseling stage, various agro-morphological and chemical traits were measured. In the physiological maturity stage, the ears relating to each replication were separated from the plants. Seed yield per plant was determined by separating the seeds on the ears of each plant and weighing it. In order to select the desired genotypes, four selection indexes including Smith-Hazel, Pesek-Baker, Brim and Robinson indices were calculated. In this study, the same weight was considered for the attributes, which is done in this way in most studies. To select the best selection index, different criteria, including the genetic gain of traits (∆G), expected gain (∆H) and relative efficiency of selection index (RE) were calculated. Results: According to analysis of variance results, the effect of genotype and stress was significant on all studied traits at the probability level of 1%. Also, the interaction effect of genotype × stress was significant on all studied traits except for flag leaf length (FLL), flag leaf width (FLW), number of leaves (NL), plant height (PH), stem diameter (SD), ear length (EL), number of rows per ear (RpE), number of grain per row (GpR), ear diameter (ED) and 100 seeds weight (HGW). In the normal conditions (without stress) in the Smith-Hazel index (optimal index), the highest coefficient (7.21 and 3.98,) was observed in FLW and ear length (EL) traits, respectively, and the lowest ones (-3.03) was observed in RpE trait. In the phosphorus deficit conditions, the highest coefficient (3.91) was observed in EL and the lowest ones (-5.35) was observed in RpE trait. In the Pesak-Baker index, under normal conditions, the highest coefficient (5.64) was observed in GpR trait and the lowest ones (-9.28) was observed in EL. In phosphorus deficit conditions, the highest coefficient (8.49) was seen in FLW trait, followed by EL (4.53) and the lowest ones (-2.17) was observed in RpE. The highest coefficient in Robinson's index under normal conditions was 2.21 for LW, which was-5.91 for that under phosphorus deficit conditions. In this index, the lowest coefficient was seen in RpE (-0.92). In Robinson's index, under phosphorus deficit conditions, the highest coefficient (1.46) was seen in EL, and the lowest ones (-5.92) was seen in FLW, followed by RpE with a value of-2.13. The Smith-Hazel index with expected gain (∆H) value of 296.306 and 229.374, and relative efficiency of (RE) of 1.0011 and 1.0839 and the Brim with expected gain (∆H) value of 296.217 and 233.083, and relative efficiency of selection index (RE) of 0.9995 and 1.0836, in normal and phosphorus deficit conditions, respectively, were the best indices. Under both normal and phosphorus deficit conditions, biomass yield, seed yield, and plant height had the highest coefficients for these indices. Based on both indices, genotype with cod number 7 and the genotype with cod number 10 are introduced as superior genotypes under normal and phosphorus deficient conditions, respectively. Conclusion: In general, the results of present investigation showed that in both normal and phosphorus deficit conditions, selection based on the Smith-Hazel and Brim indices will increase the biomass yield, seed yield and plant height due to their highest relative efficiency and expected gain. The selected genotypes after validation at the molecular level with different technologies, such as studying the expression of genes involved in tolerance to phosphorus deficit conditions using Real time PCR, can be used in the production of hybrid varieties as a way to reduce the use of phosphorus fertilizers.

Journal of Crop Breeding, 2024

Introduction and Objective: Lentil (Lens Culinaris Medik.) belongs to cool season pulses. It is a... more Introduction and Objective: Lentil (Lens Culinaris Medik.) belongs to cool season pulses. It is annual, self pollinated and diploid crop and its seed is rich in protein. Lentil, such as other legumes that are in symbiosis with nitrogen-fixing bacteria plays an important role in reducing fertilizer consumption and increasing the productivity of other crops that are in rotation with lentil. Success in breeding programs depends on genetic diversity, heritability and selection. Investigating the genetic diversity is the basis of breeding and releasing high-yielding cultivars with high quantitative and qualitative characteristics and capacities. Therefore, the evaluation of genetic diversity in crops is essential for breeding programs and the protection of genetic resources. For this purpose, it is necessary to collect plant germplasm to be evaluated as a base population, and genotypes with yield potential and other desirable traits are identified and exploited. Due to the low yield potential of the exsistance cultivars, investigating the genetic diversity among native lentil lines and comparing them with control cultivars could assiste the breeder in selecting superior lines in terms of yield potential and agromorphological triats. Material and Methods: To select and introduce new cultivars, native lentil lines collected from the target areas in Zanjan province were evaluated in the two cropping years of 2017-2018 and 2018-2019 in the experimental farm of Zanjan University's Faculty of Agriculture. In both years of the experiment, improved cultivars such as Kimia, Sabz Koohin, Gachsaran, Maragheh and Bilehsavar were used as control cultivars. The first year, the experiment was conducted in the augmented design based on randomized complete bloke design with 200 lines. Each experimental unit consisted of one metere row. The distance between the rows was 25 cm, the distance on the rows was 5 cm, and the planting depth was 5 cm. At the beginning and end of each block, two rows of Sabz Koohin were planted as borders. The second year, Due to echeaving enough seeds from the first year, the experiment was carried out in square lattice design with tow replications and larger experimental units for the selected lines from the first year. Each experimental unit consisted of two one-meter rows. The distance between the rows, the distance on the rows and the planting depth were similar to the first year experiment. At the beginning and end of each incomplete blocks, two rows of Sabz Koohin were planted as borders. Results: In the first year, the results of analysis of variance showed that there is significant difference among lentil lines in terms of canopy temperature difference, podding period, number of seed per plant, seed yield per plant, harvest index per plant, number of seed per area, seed yield per area and 1000-seed weight at 0.01and 0.05 level. in this year, canopy temperature difference, podding period, first branch height, number of pod per plant, number of vacant pod per plant, number of seed per plant, seed yield per plant, harvest index per plant, number of seed per area, seed yield per area and 1000-seed weight had high value of genetic variation coefficient, heritability and genetic advance. lines 14, 68 and 165 were the superior lines in terms of phonological traits. The height of the plant and the height of the first pod in lines 85, 92, 193 and 195 were higher than other lines. Lines 32, 90 and 156 had the highest number of full pods. Lines 122, 163, 165 and 200 had the highest seed yield per plant. The 1000-seed weight in lines 163, 166, 171 and 174 was higher in compared with other lines. The highest seed yield was observed in lines 23, 150, 192 and 200. Finaly, based on the results of comparison of mean with superior control cultivar for each trait by LSD method and considering the degree of importance of traits, the 95 superior lentil lines from 200 examined lines were selected. In the second year, the results of analysis of variance indicated a significant variation among lentil lines in terms of all studied traits except for the first branch height at 0.01 and 0.05 levels. The canopy temperature difference, number of vacant pods per plant and number of seed per plant had high value of genetic variation coefficient. High heritability was observed in the days to 50% flowering, flowering period, days to 50% podding, days to 50% physiological maturity, seed filling period and straw yield per plant. The canopy temperature difference, flowering period, first pod height, number of vacant pod per plant, seed yield per plant, biomass per plant and straw yield per plant had high genetic advance. lines 150, 155, 173 and 176 were the superior lines in terms of phonological traits. The highest plant height and the highest height of the first pod was observed in lines 146 and 180 and lines 12, 47 and 130 respectively. Lines 1, 131 and 176 had the highest number of full pods. In terms of yield and yield components per plant, lines 1, 131 and 176 had the highest number of seeds and seed yield. The 1000-seed weight in lines 23, 52, 163 and 178 was higher in compared with other lines. In terms of yield and yield components, lines 55, 69, 86, and 176 were recognized as the superior lines. Finally, based on the results of comparison of mean lines with superior control cultivar for each trait by LSD method and considering the degree of importance of traits, the 44 superior lentil lines from 100 examined lines were selected. Conclusion: The evaluated lines were significantly different from each other in terms of most traits. High heritability was observed in the days to 50% flowering, flowering period, days to 50% podding, days to 50% physiological maturatry, seed filling period and straw yield per plant. Comparing to the control cultivars, the evaluated lines had a higher mean in most of the studied traits. Therefor by selecting superior lines in terms of yield potential and agromorphological traits this genetic potential can be used to create superior population and introduce high yield cultivars.

Journal of Crop Breeding, 2024

Introduction and Objectives: The evaluation of the genotype × environment interaction effect prov... more Introduction and Objectives: The evaluation of the genotype × environment interaction effect provides valuable information regarding the yield of plant cultivars in different environments and plays an important role in evaluating the stability of the yield of breeding cultivars. Genotype × environment interaction effect, especially in stressful environments, are important limiting factors in the introduction of new cultivars; therefore, it is very important to know the type and nature of the interaction effect and reach the verities that have the least role in creating interaction effects. Various methods have been introduced to evaluate the interaction effect, each of which examines the nature of the interaction effect from a specific point of view. The results of different methods may not be the same, but the best result is obtained when a genotype with different evaluation methods shows similar results in terms of stability. The purpose of this research was to evaluate the genotype × environment interaction effect in experiments conducted in different environments, to determine the relationships between genotypes and environments and to introduce the most stable red bean genotypes. Material and Methods: In this research, 14 red bean lines along with Yakut, Ofog and Dadfar control cultivars were cultivated in the form of a randomized complete block design with three replications in Khomein, Borujerd, Shahrekord and Zanjan research stations for 2 crop years under the same conditions. After combined variance analysis, according to the significance of genotype × environment interaction, AMMI and GGE-Biplot analysis methods were used to determine the compatibility and stability of genotypes. After AMMI Analysis, the stability parameters of AMMI were calculated. In addition to the AMMI stability parameters, the simultaneous selection index was also calculated for each of the indices, which was the sum of the rank of the genotypes based on each of the AMMI stability indices and the average seed yield rank of the genotypes in all environments. Results: The significance of the double and triple interaction effects of genotype with year and place (environment) in this study showed that genotypes showed different responses in different environments, and in other words, the difference between genotypes is not the same from one environment to another, and in these conditions, the stability of grain yield can be evaluated. The contribution of about 2.5 times the interaction effect of genotype × environment from the total sum of squares, compared to the effect of genotype, indicated the possibility of the existence of megaenvironmental groups in which some genotypes show their maximum performance potential in those environmental groups. Genotypes G12, G5 and G17 had the highest seed yield among the genotypes with yields of 3288, 3136 and 3111 kg per hectare, respectively. AMMI analysis showed that the first to seventh main components were significant at the 1% probability level, and despite the significance of all model components, the first and second main components had the largest contribution to the expression of genotype × environment interaction (66.5%). Based on AMMI1 biplot Genotypes G4, G5, G16, G17 and G12 had the highest values (positive and negative) of IPCA1. In contrast, genotypes G8, G3, G2, G7 and G11 had IPCA1 values close to zero. However, only the genotype G11 showed a performance higher than the average total yield and therefore it can be introduced as a stable genotype with high general compatibility. Based on AMMI2 biplot, genotypes G2, G7, G3 and to some extent G8 and G13 were introduced as stable genotypes, but only G13 genotype had a higher yield in all environments, so this genotype can be introduced as a stable genotype with good yield.; also, every two years, the same place under investigation had a high correlation with each other, so that Bro1 and Bro2 environments on the one hand and Kho1 and Kho2 environments and finally Zan1 and Zan2 showed a high positive correlation (the same effect) to create a mutual effect. In total of the simultaneous selection indices calculated based on AMMI analysis, genotypes G11, G17, G7, G13 and G12 were introduced as stable genotypes with high yield. GGE-Biplot analysis based on average yield and stability showed that genotypes G1, G2, G3, G8 and G7 had the highest general stability compared to other genotypes despite having the lowest yield. On the other hand, G12, G5 and G17 genotypes had the highest yield with less stability. No ideal environment was observed. But Kho1, Kho2 and Sha1 environments are closer to the ideal environment than other environments and they can be used to distinguish the studied genotypes to some extent. On the other hand, G12 genotype can be considered as a desirable genotype that has high average yield and high yield stability. In the same way, G17, G5 and G11 genotypes were in the next stage compared to the ideal genotype and to some extent they can also be considered as desirable genotypes. Conclusion: According to all the results, G12 genotype can be considered as a desirable genotype that has a high average yield and also has yield stability, and G17, G5 and G11 genotypes were in the next stage.

Journal of Crop Breeding, 2024

Introduction and Objectives: Oilseed rape is one of the most important sources of vegetable oil i... more Introduction and Objectives: Oilseed rape is one of the most important sources of vegetable oil in the world, and its seed contains more than 40% of oil, and the meal obtained from oil extraction has more than 35% of protein, and currently it ranks third among oil plants after soybean and oil palm. in the world. The existance of environmental stresses, such as drought stress, causes a significant decrease in oilseed rape yields. Therefore, breeding for drought tolerance is very important, and creating high yielding and early maturing or drought tolerant cultivars is one of the important goals of breeders. The purpose of this study was to determine the best general and specific combiners and the amount of heterosis compared to the superior parent in spring rapeseed using line×tester analysis in two conditions of normal irrigation and drought stress. Material and Methods: Seven high-yielding rapeseed lines were crossed with five testers with a range of early maturity in the 2018-2019. The first generation hybrids along with 12 parents (47 genotypes in total) were evaluated in the randomized complete block design with three replications in two conditions of normal irrigation and terminal drought stress (irrigation cut off at the beginning of podding stage) in the 2019-2020. The studied traits included physiological maturity date, plant height, number of pods per plant, pod length, number of grains per pod, height of the first pod from the ground, 1000-grain weight, seed yield, oil percentage and oil yield. Results: The results of analysis of variance in both normal irrigation and drought stress conditions showed a significant difference between hybrids for all investigated traits, which indicated a significant diversity between genotypes. In analyzing the effect of hybrids into the relevant components, the interaction effect of line × tester was significant for all the traits under normal irrigation conditions and also under drought stress conditions except for the height of the first pod from the ground, and oil yield. The effect of parents versus hybrids was significant in normal for all traits except the number of seeds per pod under normal irrigation conditions and except for plant height, pod length and number of seeds per pod in drought stress conditions, which indicates the existence of heterosis for these traits. For the trait of physiological maturing, among the lines, line 6 showed the highest negative general combining ability under normal irrigation and drought stress conditions, and tester 5 showed the highest negative general combining ability among the testers under normal irrigation and drought stress conditions. Tester 5 was contributed in early maturing T5×L3 hybrid under drought stress conditions. L1 and L5 in both conditions and T2, and L3 and L4 in normal irrigation conditions and T1 in drought stress conditions were identified as the best general positive and significant combiner for the number of pods per plant, and hybrids T5×L1, T1× L5, T2×L4, T4×L4, T1×L7, T1×L6, T2×L7, T3×L2, T5×L7, and T4×L3 were the best specific combiner to increase the number of pods per plant in both experiment conditions. T4 was the most significant positive general combiner under normal irrigation conditions and drought stress for the 1000-grain trait. Also, regarding the positive significant specific combining ability for this trait hybrids T2×L7, T3×L7 in both conditions, and in addition hybrids T1×L7 and T5×L4 under normal irrigation conditions and hybrids T1×L6 and T3×L5 under drought stress conditions showed the highest amount. The most significant positive general combining ability in grain yield was determined to T5 and L1 and L6 in both conditions. The best significant positive specific combining ability were T2×L7 and T3×L7 in both conditions. The highest positive and significant amount of general combining ability of the amount of oil, was given to T3 and T5 and L6 in both experimet conditions, and T4 and L7 in normal irrigation conditions and L5 in drought stress conditions. T1×L6, T5×L1, T2×L5, T3×L1, T5×L3 and T4×L4 were among the best hybrids in both conditions. In normal irrigation conditions, T2×L3, T4×L3, T5×L1, T4×L6, and T5×L3 and in drought stress, T5×L1, T2×L3, T2×L4, T4×L4, T4×L3, T4×L5 and T2×L7 had the highest amount of heterosis in the positive direction for the number of pods per plant. The trait of the number of grain per pods, T2×L3, T4×L3, T5×L1, and T2×L5 under normal irrigation conditions and T5×L6, T3×L6, and T5×L3 under drought stress condition had the highest amount of heterosis. Conclusion: The estimation of traits' combining ability showed that T5 and L1 and L6 were the best general combiners to increase grain yield. T3×L7 and T2×L7 hybrids were the best specific combiner for increasing grain yield under normal irrigation and drought stress conditions. Also for the 1000-seed trait, T3×L6, T4×L1, T5×L4 and T1×L1 hybrids under normal irrigation conditions and T3×L7, T1×L6, T2×L6 and T3×L3 hybrids under drought stress conditions have the highest amount of heterosis. The number of pods per plant and the number of grain per pods under normal irrigation conditions, T2×L3, T4×L3 and T5×L1 had significant positive heterosisTherefore, their parents can be suggested for hybrid varieties production programs.

Journal of Crop Breeding, 2024

Background: Alfalfa is the most important leguminous forage that plays a key role in providing fo... more Background: Alfalfa is the most important leguminous forage that plays a key role in providing fodder needed for the production of human protein and dairy products. This plant has high nutritional value with high adaptability to different conditions. Alfalfa is recommended for sustainable agriculture because it has a deep root system and is a perennial plant, hence it can prevent soil erosion. Alfalfa is an excellent source for the biological fixation of air nitrogen. Researchers believe that 65% of the total nitrogen used in agriculture is through biological nitrogen fixation. It is very palatable and effective in the growth of livestock in terms of fodder quality and the optimal amount of energy from plants. In addition to protein, this plant is rich in vitamins, especially A, C, E, and K, as well as mineral compounds such as calcium. The distribution of the types of annual alfalfa at the global level, especially in arid and semi-arid regions, shows their resistance to water shortage and drought conditions. Alfalfa can be used as a successful plant to prevent desertification and the expansion of deserts. Among annual alfalfas, some species can adapt to 80-100 mm of winter rain for improvement and development in dry areas and desert pastures. However, most of Iran is suffering from water shortage, and one of the limitations of breeding for drought stress is the lack of resistance sources among crop genotypes. For this purpose, the evaluation of wild genotypes can be an important step in this direction. Methods: This research was conducted on perennial alfalfa genotypes (one variety) and one-year alfalfa (nine samples) in a factorial experiment (alfalfa genotypes and stress as the first and second factors, respectively) with three replications in a block design. Samples of alfalfa were evaluated in normal and severe stress conditions in the greenhouse of the Faculty of Agricultural Technology, University of Tehran (Abureihan Campus) during 2012-2013. The factorial experiment was conducted based on a randomized complete block design with three replications. The irrigation factor was water deficit stress including irrigation when soil moisture reached 30% of field capacity (severe stress), and the second irrigation level was normal conditions. Cultivation was carried out in May at a temperature of 22 °C, a photoperiod with 16 hours of light, and adequate humidity. Sixty medium plastic pots with an opening diameter of 15 cm, a height of 15 cm, and a capacity of 2 kg were filled with soil. Before planting, the seeds were broken by pulling soft sandpaper on their surfaces and performing stratification, followed by the seed germination test. Light irrigation was done one day before planting. Then, seven seeds were planted in each pot at a depth of 1 cm, and the soil surface was covered with cocopeat to protect soil moisture. The soil of the pots was watered with a sprinkler twice a day until the stress application. After reaching a height of 15 cm, 50% Hoagland's solution was used to feed the plants. After 55 days from the time of planting, the morphological traits, such as stem number, plant height, leaf number, internode number, internode length, leaf area, dry leaf weight, and dry stem weight, were evaluated at the vegetative growth stage. The weight method was used to adjust the soil moisture

Journal of Crop Breeding, 2024

Background: The Production of high-yielding and stable cultivars is the most important objective ... more Background: The Production of high-yielding and stable cultivars is the most important objective of crop breeding programs, including wheat. Wheat is one of the key crops cultivated in Iran. The final yield of each plant is determined by the genotype potential, the environmental effect, and the interaction effect of genotype × environment. Studies on genotype × environment interactions can help determine whether a genotype is stable in performance across a wide range of environments. Various methods (univariate and multivariate methods) have been introduced to evaluate the interaction effect, each of which examines the nature of the interaction effect from a specific point of view. The results of different methods may not be the same, but the best result is obtained when a genotype with different evaluation methods shows similar results in terms of stability. Univariate methods do not provide a complete view of the complex and multidimensional nature of genotype × environment interaction, therefore, the use of multivariate methods is suggested to solve this problem. Among the multivariate methods, genotype × genotype-environment (GGE) biplot methods are more important. Therefore, this study aimed to identify promising and stable top-performing lines of bread wheat for warm and dry climates using the GGE biplot method. Methods: The adaptability and stability of 37 promising bread wheat lines were evaluated in 10 environments, along with three checks (Chamran2, Sarang, and Mehregan). The experiment was conducted using a randomized complete block design with three replications in two cropping seasons (2020-2021 and 2021-2022) at five research stations (Darab, Ahvaz, Dezful, Khorramabad, and Zabol). In the field, each plot was planted with a density of 450 seeds/m 2. Each line was planted in plots with six four-meter lines with 20 cm line spacing. At the end of the growing season, six rows of five-meter spikes from each plot were harvested and threshed by a Wintersteiger combine. The weight of the obtained grains was measured by a digital scale and reported in hectares. Grain yield was determined using combined analyses of variance. The GGE biplot statistical method (genotype effect + genotype × environment interaction) was used to

Journal of Crop Breeding, 2024

Background: One method for selecting high-yielding cultivars is selection based on physiological ... more Background: One method for selecting high-yielding cultivars is selection based on physiological traits. Investigating the seed growth and filling process and its effect on seed weight is among the basic research in breeding programs. The speed and period of grain filling are important traits affecting grain yield in wheat, which are affected by environmental conditions. Selection based on traits such as seed filling speed and period can be a good physiological criterion for cultivar evaluation. This research aimed to evaluate the yield, speed, and period of grain-filling in bread wheat genotypes under end-of-the-season drought stress conditions and to identify superior genotypes. Methods: In this research, 18 bread wheat genotypes along with two control varieties were obtained from the Ardabil Agricultural Research Station and Natural Resources. An experiment was conducted in a completely randomized block design with three replicates in two conditions of full irrigation and drought stress at the end of the season in the Ardabil Agricultural Research Station. In the field, the genotypes were cultivated inside each plot of 4 × 3 m with a distance of 20 cm between lines and a density of 400 seeds/m 2. Genotypes were cultivated in the research station in the fall of 2019. In stress conditions, irrigation was not applied from flowering to seed maturity, while irrigation was carried out three times (early flowering, mid-seed setting, and late seed setting) from flowering to physiological maturity in stress-free conditions. Grain yield traits, grain filling speed, maximum grain dry weight, length of grain filling period, and effective grain filling period were measured in this study. Results: The results of variance analysis for the evaluated traits showed a significant difference between environments and between genotypes in all evaluated traits. The genotype × environment interaction effect was also significant for all mentioned traits. The significance of the difference between genotypes indicates genetic diversity between the studied cultivars. Moreover, the significance of the interaction effect showed that the studied genotypes did not behave the same in two environments without and with stress. The seed-filling rate of all genotypes decreased under drought-stress conditions. The average seed-filling rates were 1.20 and 1.37 mg per day in the stressed and non-stressed environments, respectively. The length of the grain-filling period and the effective grain-filling period decreased with increasing the grain-filling speed. The length of the seed-filling period in the stressed environment was shorter by 2.31 days on average. The effective length and period of seed filling were directly related to the seed dry weight. The average yield of genotypes under stress conditions (594 g/m 2) declined significantly compared to the nonstress environment (768 g/m 2). On average, the length of the seed-filling period in the stressed environment (34.90 days) was shorter than that in the non-stressed environment (37.21 days). The greatest decrease in the effective length of seed filling was observed in genotype 5 (5.30 days). The longest seed-filling periods were recorded for genotypes 14 (41 days) and 12 (40.44 days) in stress conditions, and genotype No. 13 (43.21 days) in non-stress conditions. Genotype 3 showed the shortest seed-filling period in both stress and non-stress conditions. The correlation coefficients showed a negative and significant correlation between the speed and the effective period of seed filling in the stress (r =-0.358**) and non-stress (r =-0.404**) environments. A cluster analysis of the genotypes grouped them into three and four clusters in the stress and nonstress environments, respectively. The heat map of the distribution of genotypes grouped them into three clusters based on the traits studied in the stressful environment. Genotypes 19, 18, 3,

Journal of Crop Breeding, 2024

Conclusion: Based on the findings of this study, the quinoa crop, similar to other salt-tolerant ... more Conclusion: Based on the findings of this study, the quinoa crop, similar to other salt-tolerant plants, employs various strategies (such as ionic balance and alterations in gene expression) to endure saline conditions. The research findings indicate that there was a notable rise in the NHX1 gene expression following the introduction of the sodium ion into the cytosol and receipt of the stress signal. Upon this heightened expression, the plant attempted to chelate sodium ions to mitigate the impact of stress in the vacuole. Additionally, it appears that the plant utilizes the SOS1 gene to initiate an alternative pathway for achieving tolerance and cell stability. This involves releasing sodium ions to the root area, storing them in vacuoles, preventing their buildup in the cytoplasm, and regulating sodium transport over long distances between the roots and leaves. The process also involves the selected loading of sodium ions from the xylem vessels. On the third day, there was a rise in the expression of the CMO gene at the same time as the notable rise of sodium ions in the cytosol, indicating the plant's effort to achieve osmotic equilibrium in the cell by generating glycine-betaine osmolyte and activating the proline synthesis pathway. Alternatively, the plant seeks to preserve the ionic equilibrium by boosting potassium intake and enhancing the stability of the K+/Na+ ratio to mitigate the detrimental impact of stress. Because of inadequate research on this crucial plant, the results of this study can serve as an appropriate blueprint for future research.

Journal of Crop Breeding, 2024

Background: Bread Wheat is the most extensively cultivated wheat and one of the four major crops ... more Background: Bread Wheat is the most extensively cultivated wheat and one of the four major crops in the world that constitutes the principal food of more than 30% of the world population. Biotic and abiotic environmental stressors are major factors limiting plant growth and productivity, which play a significant role in determining the yield and production potential of plants by affecting morphological, physiological, biochemical, and molecular processes. Among the abiotic stresses, the deficiency of micronutrients in the soil is important. Micronutrients regulate food metabolism in humans, and their deficiency endangers human health. Iron and zinc are essential micronutrients for human health and cofactors of many vital enzymes involved in many human metabolic processes. In plants, iron is the most required element among all micronutrients. It is a part of the catalytic group of many oxidation and reduction enzymes and is required for chlorophyll synthesis. To facilitate the adequate uptake and prevent excessive absorption of iron, plants have developed a balanced network to regulate the uptake, use, and storage of ions. In fact, such adjustment processes depend on genes that regulate ion homeostasis in plants. Due to the existence of a large allohexaploid genome and technical challenges in wheat transformation, few genes involved in iron and zinc uptake, transfer, and storage have been characterized functionally. Considering the important role of ZIP proteins in iron uptake efficiency, investigating the expression of the ZIP genes in Fe-efficient andinefficient bread wheat cultivars can be effective in improving Fe-efficient cultivars in this valuable crop. Therefore, this research aimed to evaluate the expression of ZIP3, ZIP6, and ZIP7 genes in the leaves and roots of two Fe-efficient and-inefficient bread wheat cultivars at different growth stages under iron deficiency stress. Methods: This research was carried out in a completely randomized design (CRD) based on a factorial experiment with three replications in the research greenhouse of the Faculty of Agriculture, Urmia University. The first factor was two Fe-efficient (Pishtaz) and-inefficient (Flat) bread wheat cultivars, the second factor was two soil iron levels (iron deficiency and sufficiency, respectively, 1.4 and 10 mg/kg of soil), and the third factor was two sampling stages (vegetative and reproductive, respectively, one month after planting and 30% heading). To evaluate the expression of genes, the roots and leaves of the plants were sampled at each growth stage. The seeds were obtained from the Iranian Seed and Plant Improvement Institute, disinfected with 1% hydrogen peroxide, and planted at a depth of 4 cm in the soil. The plants were irrigated using distilled water to the extent of field capacity during the growing period. Results: The results of variance analysis of the relative expression of all three studied genes showed that the interaction effect of cultivar × organ × sampling stage was significant at the probability level of 1%. The comparison of the means for the cultivar × organ × sampling stage interaction effect revealed the highest ZIP3 expression in the roots of the Fe-efficient cultivar (Pishtaz) in the vegetative and reproductive stages. The relative expression of this gene was higher in the roots of the Fe-inefficient cultivar (Falat) than that of the Fe-efficient cultivar (Pishtaz). However, the Fe-inefficient cultivar (Falat) showed the highest relative expression increase in the leaf in both reproductive and vegetative stages, but the difference in the gene

Journal of Crop Breeding, 2024

Background: In arid and semi-arid regions, biotic and abiotic stresses can directly or indirectly... more Background: In arid and semi-arid regions, biotic and abiotic stresses can directly or indirectly lead to restrictions and decreased growth of different plants. In these areas, salinity stress is one of the major challenges facing agriculture and crop production that causes huge damage to crop yields annually. The amount of salinity in the soil results in plant growth limitation, and increased soil salinity disrupts water and essential nutrient absorption for the plant and reduces plant growth, which can then lead to plant death. Reduced root growth and development, decreased nutrient absorption, increased likelihood of allergies to diseases and pests, decreased yield, and final product quality (e.g., nutrient deficiency), and increased toxic elements, are among the negative effects of salinity on plants. Various factors are involved in the creation of salinity, the most important of which can be climate change, source rock weathering, improper irrigation, drought, excessive consumption of fertilizers, and reduced seawater levels. Following climate change, these damages are on the rise every year. Due to the increase in population growth, demand for food production is increasing day by day. Wheat is known as the major grain in the supply of nutritional needs in the world, hence its sustainable production is of paramount importance. Salinity is recognized as an important factor in reducing wheat yield, and it may increase the accumulation of harmful salts in the plant tissue, which can lead to physiological damage and decreased plant growth. The effects of soil salinity vary depending on the amount of salinity, the type of salinity, and the type of wheat. One way to prevent the negative effects of salinity is to use salinity-resistant wheat cultivars. The range of diversity in relation to salt stress tolerance in different plants, especially the wheat plant, depends on various factors such as plant genotype, duration of stress, and plant growth stage. The seedling stage in wheat is one of the important stages regarding tolerance to salt stress. This study aims to investigate the response of spring wheat cultivars in the seedling stage to salinity stress. Methods: In the present study, the reaction of 64 Iranian spring wheat genotypes at the seedling stage under normal conditions and 12 dS/m salinity stress was investigated in two replications in a simple lattice design at the research greenhouse of the Faculty of Agriculture, Urmia University in 2021-2022. In this study, in the four-leaf stage, salinity stress was applied gradually for two days. The measured traits were chlorophyll (SPAD), canopy temperature, shoot length (SL), root length (RL), seedling length (PL), shoot potassium content (KS)), root potassium content (KR), shoot sodium content (NaS), root sodium content (NaR), shoot potassium to sodium ratio (KNaS), root potassium to sodium ratio (KNaR), root volume (RV), leaf area index (LAI), radicle fresh weight (FWR), radicle dry weight (DWR), relative leaf water content (RWC), shoot fresh weight (FWS), shoot dry weight (DWS), seedling fresh weight (FWP), weight dry matter of seedlings (DWP). The data of the studied traits were obtained in a random complete block design. PROC GLM was used for the analysis of variance (ANOVA) in SAS 9.4 software. The correlation was examined using PROC CORR and decomposition into factors using PROC FACTOR. The figures were grouped using the gplots software package and the biplot diagram was drawn with the factoextra software package in the R 4.1 environment. The MANOVA statement in PROC GLM was used in SAS 9.4 software for multivariate variance analysis. Results: Based on the results of ANOVA, statistically significant differences were observed between the tested cultivars based on the traits studied in the seedling stage, including FWP, DWP, FWR, DWR, FWS, RWS, and (PL). In both normal and salt stress conditions, DWP showed the most significant correlation with FWP, DWS, and DWR. Under the salinity stress conditions, FWS was significantly correlated with DWS, FWP, and DWP. Based on factor

Journal of Crop Breeding, 2024

Background: Lentil (Lens culinaris Medik) is a cool season seed legume and a good source of nutri... more Background: Lentil (Lens culinaris Medik) is a cool season seed legume and a good source of nutrients needed by humans, including protein, carbohydrates, vitamins, and minerals. The production of high-yielding and high-plant-height varieties is one of the lentil improvement goals. For this purpose, it is necessary to collect and evaluate germplasm as a base population, along with identifying and utilizing lines with high potential and other desirable traits. The environment has a significant effect on the crop production of this plant. Therefore, direct selection is important for seed yield. Since seed yield depends on the yield components, the yield and its components must be regarded as a group at the selection time to improve the yield. To properly increase yield and economic efficiency, we need to collect desirable lines with desirable genes and transfer these genes to cultivated lines to produce desirable cultivars. Consequently, sufficient information is necessary on accessible genetic materials, which is possible by evaluating different traits. Methods: To assess the model of the simultaneous effect of traits on the lentil seed yield for determining the selection procedure in native lentil lines of Zanjan province, an experiment was conducted in the research farm of the Faculty of Agriculture, Zanjan University, during two cropping years 2017-2018 and 2018-2019. In both years of the experiment, improved cultivars, such as Kimia, Sabz Kohin, Gachsaran, Maragheh, and Bilehsavar, were used as control cultivars. The first-year experiment was conducted in an augmented design based on a randomized complete block design with 200 lines. Each experimental unit included a 1-m row. The distance between the rows was 25 cm, the distance between plants in a row was 5 cm, and the planting depth was 5 cm. Two rows of Kohin-Sabz lentils were planted as margins at the beginning and end of each block. Due to obtaining a sufficient amount of seeds from the first year, the second-year experiment was carried out as a simple lattice design with two replications and larger experimental units for the lines selected from the first year. Each experimental unit included two 1-m lines. The distance between the rows, the distance between plants in a row, and the planting depth were similar to the first-year experiment. Two rows of Kuhin green lentils were planted as margins at the beginning and end of each incomplete block. The measured traits included phenological and morphological traits, yield, and yield components per plant and unit area. Results: Among the studied traits, the highest coefficient of variation was obtained for the number of seeds, biomass, straw yield, and seed yield. The coefficient of correlation showed that the number of seeds and seed yield were positively and significantly correlated with phenological traits, such as the podding period, physiological maturity, and seed-filing period, as well as morphological traits such as plant height and first branching height, respectively. A positive and significant correlation was observed between the number of seeds and seed yield with the number of pods per plant and biomass per plant. In regression analysis by the stepwise method, plant height was the first trait entered into the model, which could explain 46.8% of the variation related to seed yield per plant. Then, the number of seeds per plant, 1000-seed weight (TSW), straw yield per plant, and the seed-filling period were entered into the model, respectively, which could totally explain 67.5% of the variation related to seed yield per plant. The results of the path analysis showed that the number of seeds per plant had the most considerable direct and positive effect on seed

Journal of Crop Breeding, 2024

Background: Lentil (Lens culinaris Medik.) is one of the main food legume crops in Iran, where it... more Background: Lentil (Lens culinaris Medik.) is one of the main food legume crops in Iran, where it is grown as a rainfed crop in spring in cold regions. One of the obstacles of spring cultivation in cold regions is drought stress exposure at the end of the growing season in the late cultivation date, which dramatically increases null pods and decreases seed yield. Until introducing autumn cultivation, specific, and cold-tolerant lentil varieties, the only solution for this problem is to find ways to deal with the damage of drought stress. Nanotechnology serves as a precursor of the new industrial revolution that has the potential to bring alteration in agricultural production. Nanoparticles (NPs) have been applied for enhancing seed germination, growth, physiology, productivity, and quality traits of various crops under normal or stressful conditions. Therefore, to reduce the negative effect of drought stress at dryland conditions in late cultivations, the effect of ZnSO4 and Fe2O3 NPs at 0.5% and 1% were studied on the agronomic, physiologic, root traits, and antioxidant system of lentils in the cold region. Methods: A field study was carried out at the Dryland Agricultural Research Center (DARI) in Maragheh during the 2019-2020 growing season. Experiments were conducted in rainfed conditions using a complete block design with three replications. Treatments were no spray, 0.5% nano ZnSO4, 1% nano ZnSO4, 0.5% ZnSO4, 1% ZnSO4, 0.5% nano Fe2O3, 1% nano Fe2O3, 0.5% Fe2O3, and 1% Fe2O3. Treatments were applied at two stages (10 days after the plant first establishment and 50% of flowering) in the early morning and not on windy days. The Bilesavar variety, which is suitable for spring cultivation in cold regions, was used in this experiment. Plant height, relative water content (RWC), cell membrane stability (CMS), canopy temperature, and the normalized difference in the vegetative index (NDVI) were recorded during the growing season. The seed yield and 100 seed weight (HSW) were calculated after harvesting. The activity of ascorbate peroxidase (ASP), catalase (CAT), glutathione peroxidase (GPX), superoxide dismutase (SOD), peroxidase (POX), and the contents of proline, chlorophyll a, chlorophyll b, and carotenoids were calculated in gathered leaf samples during the growing season. Results: Differences between treatments were significant for RWC, CMS, canopy temperature, NDVI, and seed yield at 1%, and for HSW at 0.5%. The highest seed weight was observed in using nano Fe2O3 0.5%, and the lowest belonged to no spray treatment. The lowest RWC, CMS, and the highest canopy temperature were recorded in no spray treatment. Analysis of variance results showed that differences between treatments for all biochemical traits were significant at the 1% level. Chlorophylls a and b contents increased using NPs, and the highest level belonged to 1% nano ZnSO4 treatment and as expected the lowest calculated in no spray treatments. The highest carotenoids, and the activities CAT, ASP, GPX, and SOD were observed in 1% nano ZnSO4 treatment. The lowest activity of these enzymes as well as the highest H2O2, proline, and malondialdehyde (MDA) belonged to no spray treatment. According to the results, seed yield was significantly correlated with CAT (0.

Journal of Crop Breeding, 2024

Background: About 30% of the world's sugar needs are provided by sugar beet and sugar cane. Many ... more Background: About 30% of the world's sugar needs are provided by sugar beet and sugar cane. Many biotic factors, such as pests, diseases, and weeds, decrease production and damage sugar beet fields. To bring sugar beet production to its real potential and maintain it at this level, it is necessary to identify biotic stress-causing factors, determine their individual role in reducing the yield, and investigate their management and control methods. One of the pests of sugar beet is the root aphid that settles on the secondary roots and causes dwarfism and wilting of the plants by feeding on plant sap. It also causes a decrease in root weight and a 30-36% decrease in sugar content. Due to the special conditions of the aphid's life under the soil, the effect of the aphid's white wax secretions on soil non-wetting by the poison solution, and the lack of a suitable systemic poison, the use of chemical poisons in the form of soil-water is not recommended in controlling this pest. Therefore, the most effective method for managing this pest in sugar beet fields is to use resistant and tolerant cultivars. Therefore, this research aimed to evaluate the resistance of domestic and foreign cultivars to this type of aphid. This study also investigates the effect of this pest on their quantitative and qualitative yields to use them or their ancestors in future breeding programs to produce resistant cultivars. Methods: The resistance to root aphid of eight sugar beet cultivars (Asia, Arta, Dena, Shokoofa, biopolymerized Shokoofa, Nika, Palma, and BTS505) and the effect of this pest on their quantitative and qualitative yields were evaluated in a pilot experiment based on a randomized complete block design with four replications in the West Azarbaijan Agricultural and Natural Resources Research Center, agricultural education center of Miandoab city, in 2023 crop season. To this aim, sugar beet root aphid was sampled by harvesting 20 sugar beet roots (four replicates per cultivar) in the middle of September. The samples were grouped into four resistant, semiresistant (tolerant), sensitive, and very sensitive groups based on the percentage of sugar beet roots infected with aphids. Traits related to quantitative and qualitative yields were also measured after harvesting. Results: The results of the analysis of variance showed that the effect of the cultivar was significant on all measured traits (p ≥ 0.01). The highest and lowest values of the genotypic and phenotypic coefficients of variation belonged to the percentage of aphid-infected roots (46.52% and 46.73%, respectively) and the sugar extraction coefficient (4.55% and 4.69%, respectively). Based on the results from mean comparisons for the cultivars, the highest and lowest values of the root yield trait was measured in BTS505 and Palma foreign cultivars with 82.35 and 62.81 t.ha-1 , respectively, which were placed in two statistical groups. However, the average root yield of the Palma cultivar with the lowest root yield was not significantly different from the Shokoofa cultivar (64.41 t.ha-1). The highest sugar content trait belonged to the BTS505 foreign cultivar (16.86%), and the lowest values were obtained for the Palma foreign cultivar and the Shokoofa domestic cultivar (12.65 and 13.01%, respectively). No significant differences were observed between the domestic and foreign cultivars in the averages of the root yield trait (69.56 and 72.58 t.ha-1 , respectively) and sugar content (14.25 and 14.75%, respectively). This indicates the genetic progress of the newly introduced domestic hybrid cultivars in terms of these two important traits that influence the final yield of sugar. In terms of the percentage of aphid-infected roots, the

Journal of Crop Breeding, 2024

Background: Chickpea (Cicer arietinum L.) is a legume grown in cool season areas. It is one of th... more Background: Chickpea (Cicer arietinum L.) is a legume grown in cool season areas. It is one of the main sources of protein and energy and plays a major role in improving soil fertility. Peas are divided into two classes, Desi and Kabali. The Desi seed is smaller, wrinkled, and darker while Kabli has a lighter, whiter seed color, larger seed size, and smooth surface. The chickpea yield is 1199 kg per hectare in America, 1261 kg per hectare in India, and 409 kg per hectare in Iran. Until 2005, this plant was called an orphan plant due to the insufficient genetic resources in chickpeas, but the plant was known as a plant with a rich genomic resource after many efforts at national and international levels. Further studies on chickpea genetic diversity are important to improve the yield. Chickpeas have plenty of diversity in different geographical regions, and the genetic pattern and the amount of variation within and between these populations should be known to progress breeding programs and effectively use these germplasm collections. The evaluation of genotypes faces two key challenges. The first is the genotype-environment interaction, and the second is the interaction between the studied traits. This study aimed to investigate the genetic diversity in the Desi chickpea germplasm under autumn cultivation conditions, analyze the relationships of morphological-agronomical traits, and select superior genotypes in terms of all morphologicalagronomical traits. Methods: This study was conducted on 416 genotypes, including 335 landrace of Iran, 1 ICARDA genotype, and 78 ICRISAT genotypes, along with two checks named Kaka and Pirouz cultivars in the experimental farm of the Dryland Agricultural Research Institute (Kermanshah). The cultivars were evaluated in terms of morphological-agronomic traits, including the number of days to flowering, the number of main branches, the number of secondary branches, the number of pods per plant, plant height, the end number of days to maturity, seed yield, and 100-seed weight (HSW). The experiment was conducted during 2020-2021 under autumn sowing conditions and as an augmentation based on a randomized complete block design with nine blocks. The variance, heritability, and genetic advance were analyzed with the R software packages (augmentedRCBD). The R software package (metan) and (GGEBiplotGUI) were used for the biplot analysis of the genotype by trait. Data were grouped using the K-mean algorithm, single method, and Euclidean distance with R software. The R software package (NbClust) was used to calculate the number of appropriate groups resulting from the cluster analysis. Using the R software package (metan) with the selection index (MGIDI), the top genotypes were ranked based on several traits. Results: The results of the analysis of variance were significant for the number of days to maturity, HSW, and plant height. The highest and the lowest coefficients of variation belonged to the number of secondary branches and days to maturity, respectively. The plant height and HSW traits had high values of heritability and genetic advancement. According to the results of the genotype by trait biplot, genotypes 148, 327, 391, and 277 were in the best conditions in terms of HSW, days to maturity, plant height, and days to flowering. Genotypes 6, 400, 18, 42, 26, 168, 15, and 2 were in the best conditions for the number of pods per plant, seed yield, the number of main branches, and the number of secondary branches per plant. According to the findings of the genotype by trait biplot, most of the selected genotypes were from the landrace of the Iranian chickpea. Clustering was performed using the K-means method, which divided the genotypes into two groups. In the second group, genotypes 6, 18, 148, 327, and 91 had more distances (according

Journal of Crop Breeding, 2024

Background: Alfalfa is one of the key fodder plants due to its species diversity and high stresst... more Background: Alfalfa is one of the key fodder plants due to its species diversity and high stresstolerance range. In addition to producing significant palatable fodder, this plant stabilizes air nitrogen through symbiosis with rhizobium and causes soil fertility in addition to meeting its own needs. For fodder production in the hot and dry region of Sistan as the hub of animal husbandry in the province, it is inevitable to investigate and introduce high-yielding alfalfa cultivars. Therefore, the present research aimed to evaluate tropical alfalfa cultivars and identify high-yielding and more compatible cultivars in terms of yield production and selection of stands with suitable potential for selection. Methods: The phenological, morphological, and functional traits of 10 tropical alfalfa genotypes (Zabol local purified alfalfa, Zabol local mass, Baghdadi, two Afghani masses, Nikshahri, Omid, and lines 473, 472, and 471) were investigated in the Zahak Agricultural and Natural Resources Research Station, located 20 km from Zabol city. An experiment was conducted in a statistical design of randomized complete blocks with three replications during 2017-2018. The bed preparation, including plowing, disk, and leveling, was operated exactly the same for the replications. The distance between the plots in each block was 75 cm, and the distance between the blocks in each replication was 1 m. After preparing the bed on November 15, 2016, furrows were created at a distance of 30 cm (four lines of 6 m) in the plots, and seeds with 95-100% germination capacity were planted at a rate of 15 kg per hectare. Seeds were sown in a row manually by opening grooves to a depth of 1 cm using the method of Hiramkari. During the experiment, the operation consisted of irrigation every 15 days in winter, spring, and summer (once a week) according to the needs. Weeds were mechanically weeded in the early stages of growth. In each year, eight plants were harvested at the 20% flowering stage. Days to greening, days to flowering, plant height, leaf-to-stem percentage, stem diameter, stem number, dry matter percentage, and wet and dry fodder yields were the traits measured during the experiment. At the end of the experiment, data on the fodder yield and morphological and phenological traits of alfalfa cultivars were analyzed using MSTAT-C software. The correlation was calculated using SPSS 16 software. Analysis into principal components and the biplot were done using the Past software. The means of traits were compared with Duncan's test at the probability level of 5%.

Journal of Crop Breeding, 2024

Background: Wheat is the key crop in many parts of the world that has the largest cultivated area... more Background: Wheat is the key crop in many parts of the world that has the largest cultivated area. As much as 30% of all grains produced in the country belong to wheat, which is known as the main food of half of the world's people. At the same time, environmental stresses, including biotic stresses, have been one of the most important factors in reducing wheat yield in recent years. Powdery mildew (Blumeria graminis f.sp. tritici) is one of the important diseases of wheat that causes great losses to wheat production every year. On the other hand, the resistance of resistant wheat genotypes is not constant over time, and the resistance of almost all resistance genes commonly used in the world has been broken by new pathogenic strains of powdery mildew. This is because research has shown that the high pressure imposed by resistance genes on disease-causing populations has caused the rapid evolution of new pathogenic races, resulting in the loss of resistance. For this reason, one of the most effective and logical methods of controlling this disease, which is most compatible with the environment and sustainable agriculture, is the identification and production of resistant cultivars. Methods: In the present study, 32 different bread wheat genotypes (Triticum aestivum L.

Journal of Crop Breeding, 2024

Background: As one of the most important cereals, bread wheat is an essential part of food securi... more Background: As one of the most important cereals, bread wheat is an essential part of food security in the world, which supplies one-fifth of the total calories of the world population. Nowadays, the yield of wheat has been affected by climate change-driven drought as one of the most important abiotic stresses that has become an important threat to food security in the world. Root and stomatal traits are especially important in breeding plants to withstand drought stress. Stomata play a key role in controlling carbon dioxide uptake and water loss through transpiration. Therefore, stomatal characteristics are used as indicators of water status and plant growth, especially in drought stress conditions. Having a wide range of physiological and morphological characteristics, roots play an essential role in absorbing water and nutrients. They are also the first organ that sends signals to control the stomata in response to dryness. Therefore, the difference in the structure of the root system can cause the difference between the performance in different cultivars. This study was conducted to investigate stomatal characteristics and their relationship with the root system and plant performance in 24 bread wheat lines and cultivars. Methods: To investigate the relationship between stomatal dimensions and density with the root system, an experiment was conducted on 24 bread wheat genotypes in the form of a randomized complete block design with three replications in the rainfed conditions of the research farm at Zanjan University Faculty of Agriculture in the crop year 2018-2019. In this experiment, PVC pipes were used to study the root system. Twelve seeds were planted in each tube, which were thinned to seven after germination. In each experimental unit, there were two tubes for each genotype, one of which was used to evaluate traits and final yield, and the second tube was used for root studies. Stomatal traits, including the length and width of stomata and number of stomata per unit area, root traits including root length, root diameter, root volume, root surface, and root biomass, and seed yield were measured in the end. The resulting data from the measured traits were analyzed in the form of a randomized complete block design, and the averages were compared using the LSD method. The data were analyzed using multivariate statistical analyses, including regression analysis, path analysis, and factor analysis, and cluster analysis was used to group genotypes. Statistical calculations were done using SAS 9.0 and SPSS 21 software. Results: The results of analysis of variance and mean comparison showed high variability among genotypes for all measured traits. The results of the mean comparison of genotypes showed that genotypes 2, 5, 8, and 16 had the highest yield, and genotype 23 had the lowest yield among the examined genotypes. The highest number of stomata on the upper and lower leaf surfaces belonged to genotypes 5 and 2. In terms of root traits, the highest diameter, volume, length, root surface, and root dry weight at a depth of 0-25 cm were recorded for genotypes 2, 3, 18, and 5, respectively. There was a high and significant correlation between the

Journal of Crop Breeding, 2024

Introduction and Objective: Salinity stress is one of the most important limitations of rice cult... more Introduction and Objective: Salinity stress is one of the most important limitations of rice cultivation worldwide. On the other hand, the use of physical and chemical mutagens can be very important not only to the development and combination of new genes or alleles with agricultural importance but also to introduce genotypes more adaptable and stable to adverse weather and soil conditions. For this reason, with the development and progress of rice varieties that are tolerant and adapted to salinity, it is possible to increase the sustainable production of this stable food. Therefore, the present study was conducted with the aim of investigating the response of the tenth generation (M10) of rice mutants to salinity stress in the reproductive stage using agronomic and biochemical characteristics. Material and Methods: In this research, 13 mutant lines of Seng-e-Tarem, Hashemi and Khazar cultivars using gamma ray irradiation from Cobalt 60 which have been previously identified as tolerant lines in molecular studies were used along with the tolerant cultivars of Nonabukra and Deylamani and sensitive cultivars of IR29 and Sepidrood. The genotypes were exposed to three levels of salinity (0, 4 and 8 dS/m) from the source of sodium chloride. A factorial experiment based a randomized complete block design (RCBD) and a factorial split based a RCBD with three replicates were used to evaluate agronomic traits along with yield and biochemical traits, respectively. The measured parameters were tillers number (TN), the number of filled (NFG) and unfilled grains (NUG), 1000 grains weight (TGW), plant height (PH), Days to 50% of flowering (DTF) and the paddy yield (PY), and for the biochemical traits, the activity of catalase (CAT) and superoxide dismutase (SOD), protein (PN), proline (PR) and malondialdehyde (MDA) contents and electrolyte leakage (EL) percentage. Results: The results of the variance analysis showed that the effect of salinity and genotype and their interactions were significant for all the measured traits. A wide range of genetic diversity was observed among the genotypes for the agronomic and biochemical traits. Among the traits, PY was identified as the best and the most indicative trait to classify the tolerant genotype under salt stress conditions. Among the investigated mutants at different levels of salinity, the highest PY was recorded in MP6, MP10 and Deylamani genotypes, respectively. PY value in MP10 mutant at the salinity level of 8 dS/m was closed to Deylamani variety (tolerant check). With the increase of salinity from zero to 8 dS/m, the measured traits adversely affected. The cluster analysis diagram of studied genotypes based on agronomic traits and PY at a salinity level of 4 dS/m classified the genotypes into three separate groups. The genotypes MP2, MP3, MP4, MP9, and MP10 were grouped in the second group, in which Deylamani cultivar was also present as a tolerant check. The cluster analysis diagram of agronomic traits and PY at the salinity stress level of 8 dS/m divided the genotypes into four different groups. In the third group, two genotypes of MP9 and MP10 were included with Tarem Deylamani variety (tolerant check). The correlation coefficient between agronomic traits in 8 dS/m of salt conditions showed that PY had a positive and significant correlation with PH (r=0.51), the NFG (r=0.88) and TGW (r=0.63). Also, there is a negative correlation between DTF with PH (r=-0.70) and NFG (r=-0.62) and a positive and significant correlation with TN (r=0.60). Biplot analysis divided the studied lines into four groups based on agronomic traits at a salinity level of 4 dS/m. The first group includes six mutant lines as very sensitive group, the second group includes two mutant lines as sensitive group, the third group with three genotypes including lines MP9, MP10 and Tarem Deylamani variety (tolerant check) as tolerant group and the fourth group with six genotypes included lines MP11, MP12, MP13 and Nonabukra variety (international tolerant check) as well as Sepidrood and IR29 varieties as high salt tolerant group. Also, biplot analysis based on agronomic traits at a salinity level of 8 dS/m divided the studied lines into four groups. The first group consisted three mutant lines as very sensitive group, the second group included six lines as sensitive group, the third group involved five genotypes including MP11 and MP13 lines and Nonabukra varieties (tolerant check), Sepidrood and IR29 as the tolerant group and the fourth group with three genotypes included MP9 and MP10 lines and Tarem Deylamani variety (native tolerant check) as high salt tolerant group. For biochemical traits at 8 dS/m of salt stress, the highest amount of SOD was recorded in Deylamani cultivar (tolerant check), PN for MP2 mutant, PR for MP3 mutant, and the lowest amount of EL and MDA was recorded for MP2 and MP10 mutants, respectively. Conclusion: In general, PY of MP10 mutant line in salt stress conditions was closed to Deylamani as a native salt tolerant cultivar, therefore could be introduced as a superior line for further research in saline conditions.

Journal of Crop Breeding, 2024

Introduction and Objective: Black rust is one of the important fungal diseases that widely affect... more Introduction and Objective: Black rust is one of the important fungal diseases that widely affects the quantity and quality of wheat in many regions of the world. The damages caused by black rust disease can be more than other pathogens in wheat and its importance is such that millions of hectares of healthy fields with high production potential can be destroyed in less time. Destroy it completely in one month. Resistance is one of the genetic characteristics of the host that plant breeders use to produce cultivars. Lines that are recognized as resistant in a survey can be used as a source of resistance in another breeding program. Genetic resistance reduces or eliminates the consumption of chemical poisons, and as a result, it is considered as the most economical and healthiest method of combating plant diseases. Accordingly, in order to statistically investigate some physiological markers related to resistance to black rust disease, 24 bread wheat genotypes including 8 cultivars and 16 promising lines were studied. In this study, two varieties MV-17 (disease-resistant variety) and Morocco (disease-susceptible variety) were selected as controls in this study due to their different behavior in resistance to wheat black rust. Material and Methods: This experiment was carried out in 2019 in the greenhouse of the Research Institute of Plant Breeding and Seed Preparation under the conditions of infection and non-infection with the native race TKTTF of wheat black rust disease and in the form of a randomized complete block design with four replications. Physiological traits including relative leaf water content (RWC), cell membrane stability (MP), electrical conductivity (EC), chlorophyll content (SPAD) and chlorophyll fluorescence were measured and recorded. Results: At the probability level of 1%, a significant difference between genotypes was observed and the interaction effect of disease x genotype was significant for all traits, which indicates the non-homogeneous difference of genotypes for the studied traits in two conditions of infection and non-infection. Also, for all measured traits, there was a significant difference between two different levels of disease infection, which shows the effect of the black rust pathogen on the relative content of leaves, membrane permeability, electrical conductivity, chlorophyll concentration, primary fluorescence, fluorescence It has maximum, variable fluorescence and photochemical efficiency of photosystem II. The results showed that pathogen contamination increases the relative water content, chlorophyll concentration, membrane permeability, initial fluorescence, maximum fluorescence, variable fluorescence, photochemical efficiency of photosystem II and decrease in electrical conductivity. Based on all studied physiological traits of genotypes MV-17, C-98-17, C-98-11, C-98-5, C-98-12, C-98-18, C-98-16, C-98-3 and CD-94-9 were identified as the genotypes that showed more resistance to the disease agent. There was a high correlation between initial fluorescence, maximum fluorescence, variable fluorescence, photochemical efficiency of photosystem II, membrane permeability and electrical conductivity in response to stem rust. Based on Ward's cluster analysis and detection function analysis, the genotypes were divided into four separate groups in the conditions of infection and non-infection with black rust. They were placed in a group. While, in the condition of no disease contamination, 6, 9, 4 and 5 genotypes were clustered in four separate groups, respectively. Conclusion: This study showed the effect of East Azerbaijan stem rust TKTTF race on the physiological traits of winter cultivars and lines of wheat. This race caused changes in the studied physiological traits in both experimental conditions, from this output it can be concluded that the resistant lines are more resistant to the disease than the commercial variety and are recommended as selected lines in breeding programs should be used. It is worth mentioning that according to the results of the grouping of genotypes and also the placement of valuable genotypes in terms of relative water content traits, membrane permeability index, chlorophyll content, initial fluorescence, maximum fluorescence, variable fluorescence, and photochemical efficiency. Photosystem II and electrical conductivity in the first and second groups in the conditions of disease infection and non-infection, it was concluded that the results of cluster analysis had a good relationship with the results of variance analysis and comparing the average of the studied traits. The results showed that the physiological traits measured in response to black rust disease have diversity. Therefore, possible genotypes with resistance to this pathogen can be identified by using the changes of these traits. Also, considering the relationship between the results obtained from the evaluation of physiological and pathological traits, the possibility of using physiological traits as indicators related to resistance to wheat black rust disease was benefited. In other words, the physiological indicators used were able to detect the existence of diversity and response to resistance to black rust disease and they can be used as physiological indicators related to resistance to black rust disease of wheat. Examining different traits in different environmental conditions has shown that the way the genotypes act and respond to the pathogen changes with the change of environmental conditions. For this purpose, these studies should be carried out in several years and in different environments. It is also recommended to carry out the above test using agricultural traits at the stage of the sorghum plant as well as biochemical traits related to the disease.

Journal of Crop Breeding, 2024

Introduction and Objective: The genetic diversity of plant species and their relationship with wi... more Introduction and Objective: The genetic diversity of plant species and their relationship with wild species is very important to improve the yield of crops..The first step in the improvement of medicinal plants is to identify and collect endemic genotypes.Endemic genotypes are very important in the selection of cultivars due to their adaptability to the climate of the region. Mentha longifolia is one of the important endemic medicinal plants of Iran, which is used in various pharmaceutical, food and cosmetic industries. Essential oil, phenolic compounds, flavonoids and other compounds such as steroids and ceramides are important chemical compounds in oregano plant. In this study, morphological diversity, essential oil and antioxidant activity of 20 Mentha longifolia genotypes in West and East Azerbaijan provinces were investigated. The aim of this research, on the one hand, is to know the potential and range of diversity of Menta longifolia genotypes in its natural habitats in West Azarbaijan and East Azarbaijan provinces. On the other hand, the introduction of regions with superior genotypes in terms of these traits is for use in breeding programs. Material and Methods: The collection of plant samples from some areas of two northwestern provinces of Iran (West Azerbaijan and East Azerbaijan) was done in the spring of 2022. In order to evaluate the morphological traits of the plant in the flowering season, 11 quantitative traits of the plant including plant height, inflorescence length, crown diameterstem diameter, internode length, leaf length, leaf width, number of leaves, number of inflorescences, fresh weight, dry weight and the number of sub-branches were evaluated. After drying the plant samples, essential oil extraction was done using a clonger, and the essential oil samples were transferred to Urmia University Jihad to identify compounds by gas chromatography. Extraction of plant samples was done by ultrasonic method. Antioxidant activity was evaluated by DPPH method. All the obtained data were analyzed with three repetitions and based on a completely random design using SPSS software. LSD test was used to compare the mean data. Data clustering was done based on Ward's method and Euclidean distance square measure. Principal component analysis was performed on the data .Also, in this study, correlation between studied traits was done by R software. Results: The results of analysis of variance showed that the genotypes collected from different regions have significant differences in terms of plant height, inflorescence length, crown diameterstem diameter, internode length, leaf length, leaf width, number of leaves, number of inflorescences, fresh weight, dry weight and the number of sub-branches are investigated (P < 0.01). The results of the analysis of the percentage and chemical composition of the essential oil showed that the type of genotype had a significant effect on the amount of these compounds in different genotypes of Mentha longifolia (P < 0.01). Among the studied genotypes, the highest percentage of essential oil and the amount of Trans-Caryophyllene and Germacrene D compounds were found in G18 of Iranq region of Tabriz, also the highest amount of Alpha-Terpineol and Spathulenol was found in G16 of Aghajari region of Maragheh. Also, there was a significant difference between different genotypes of mint in terms of antioxidant activity. The maximum amount of antioxidant activity (80.81%) was observed in G3 of Hachesu area in Shahindej. Based on Ward's cluster analysis, the genotypes were divided into three main groups. G1 alone was placed in a separate group due to the high content of Spathulenol and high antioxidant activity. The second group, which includes most of the genotypes (G2,

Journal of Crop Breeding, 2024

Introduction and Objective: Maize (Zea mays L.) is the third most important cereal after wheat an... more Introduction and Objective: Maize (Zea mays L.) is the third most important cereal after wheat and rice, which accounts for 26% of total cereal cultivated area and 37% of their production. Maize is a valuable raw material for extracting oil, starch, alcohol, glucose, plastic, lactic acid, acetic acid, acetone and paint, and it is possible to made paper, cardboard, and nitrocellulose from its stalks. As an important nutrient, phosphorus plays important role in energy transfer, photosynthetic oxidation-reduction reactions, as well as in biochemical compounds including nucleic acids, structural proteins, enzymes, and signal transmission. Due to the predominance of calcareous soils with high pH in arid and semi-arid agricultural climates, the amount of available phosphorus is limited. In order to increase available phosphorus for plants, large amounts of phosphorus chemical fertilizers are needed regularly. However, a large amount of phosphorus in fertilizers may be converted to insoluble phosphate, immediately by reaction with calcium in the soil after its application. On the other hand, indiscriminate use of phosphorus chemical fertilizers leads to many environmental problems such as surface runoff of phosphorus, eutrophication of aquatic ecosystems, reduction of biodiversity and abnormal changes in soil salt concentration and pH. Breeding cultivars that absorb phosphate or phosphorus more efficiently is one of the solutions to deal with the stress of phosphorus deficiency as a trait with low heredity. The use of selection indices can be an effective method for the indirect selection of traits with complex genetics. Material and Methods: 93 maize genotypes prepared from different research centers were evaluated in terms of agromorphological traits under normal and phosphorus deficit conditions using completely randomized design with three replications in the crop year 2016-2017 in an open area conditions. For this purpose, after analyzing the soil of different regions, soil with low phosphorus content (7.240 mg/kg) was selected and the pots (15 kg) were filled with soil and sand in a ratio of two to one. Usable soil phosphorus was determined by the Olsen method in the soil science laboratory of Urmia University. In both optimal and phosphorus deficit conditions, soil was strengthened with nitrogen fertilizers (in the amount of 9 g/pot (during three stages during the growth period)), potassium sulfate (in the amount of 13.5 g/pot), Sequestrin (1.5 g /pot), manganese sulfate (0.225 g/pot), zinc sulfate (0.99 g/pot), copper sulfate (0.3 g/pot) and boric acid (0.21 g/pot). In optimal conditions, phosphorus fertilizer in the form of triple superphosphate was added to each pot in the amount of 6 g/pot. Phosphorous fertilizer was not added to the soil in the phosphorus deficit conditions. With the beginning of the tasseling stage, various agro-morphological and chemical traits were measured. In the physiological maturity stage, the ears relating to each replication were separated from the plants. Seed yield per plant was determined by separating the seeds on the ears of each plant and weighing it. In order to select the desired genotypes, four selection indexes including Smith-Hazel, Pesek-Baker, Brim and Robinson indices were calculated. In this study, the same weight was considered for the attributes, which is done in this way in most studies. To select the best selection index, different criteria, including the genetic gain of traits (∆G), expected gain (∆H) and relative efficiency of selection index (RE) were calculated. Results: According to analysis of variance results, the effect of genotype and stress was significant on all studied traits at the probability level of 1%. Also, the interaction effect of genotype × stress was significant on all studied traits except for flag leaf length (FLL), flag leaf width (FLW), number of leaves (NL), plant height (PH), stem diameter (SD), ear length (EL), number of rows per ear (RpE), number of grain per row (GpR), ear diameter (ED) and 100 seeds weight (HGW). In the normal conditions (without stress) in the Smith-Hazel index (optimal index), the highest coefficient (7.21 and 3.98,) was observed in FLW and ear length (EL) traits, respectively, and the lowest ones (-3.03) was observed in RpE trait. In the phosphorus deficit conditions, the highest coefficient (3.91) was observed in EL and the lowest ones (-5.35) was observed in RpE trait. In the Pesak-Baker index, under normal conditions, the highest coefficient (5.64) was observed in GpR trait and the lowest ones (-9.28) was observed in EL. In phosphorus deficit conditions, the highest coefficient (8.49) was seen in FLW trait, followed by EL (4.53) and the lowest ones (-2.17) was observed in RpE. The highest coefficient in Robinson's index under normal conditions was 2.21 for LW, which was-5.91 for that under phosphorus deficit conditions. In this index, the lowest coefficient was seen in RpE (-0.92). In Robinson's index, under phosphorus deficit conditions, the highest coefficient (1.46) was seen in EL, and the lowest ones (-5.92) was seen in FLW, followed by RpE with a value of-2.13. The Smith-Hazel index with expected gain (∆H) value of 296.306 and 229.374, and relative efficiency of (RE) of 1.0011 and 1.0839 and the Brim with expected gain (∆H) value of 296.217 and 233.083, and relative efficiency of selection index (RE) of 0.9995 and 1.0836, in normal and phosphorus deficit conditions, respectively, were the best indices. Under both normal and phosphorus deficit conditions, biomass yield, seed yield, and plant height had the highest coefficients for these indices. Based on both indices, genotype with cod number 7 and the genotype with cod number 10 are introduced as superior genotypes under normal and phosphorus deficient conditions, respectively. Conclusion: In general, the results of present investigation showed that in both normal and phosphorus deficit conditions, selection based on the Smith-Hazel and Brim indices will increase the biomass yield, seed yield and plant height due to their highest relative efficiency and expected gain. The selected genotypes after validation at the molecular level with different technologies, such as studying the expression of genes involved in tolerance to phosphorus deficit conditions using Real time PCR, can be used in the production of hybrid varieties as a way to reduce the use of phosphorus fertilizers.

Journal of Crop Breeding, 2024

Introduction and Objective: Lentil (Lens Culinaris Medik.) belongs to cool season pulses. It is a... more Introduction and Objective: Lentil (Lens Culinaris Medik.) belongs to cool season pulses. It is annual, self pollinated and diploid crop and its seed is rich in protein. Lentil, such as other legumes that are in symbiosis with nitrogen-fixing bacteria plays an important role in reducing fertilizer consumption and increasing the productivity of other crops that are in rotation with lentil. Success in breeding programs depends on genetic diversity, heritability and selection. Investigating the genetic diversity is the basis of breeding and releasing high-yielding cultivars with high quantitative and qualitative characteristics and capacities. Therefore, the evaluation of genetic diversity in crops is essential for breeding programs and the protection of genetic resources. For this purpose, it is necessary to collect plant germplasm to be evaluated as a base population, and genotypes with yield potential and other desirable traits are identified and exploited. Due to the low yield potential of the exsistance cultivars, investigating the genetic diversity among native lentil lines and comparing them with control cultivars could assiste the breeder in selecting superior lines in terms of yield potential and agromorphological triats. Material and Methods: To select and introduce new cultivars, native lentil lines collected from the target areas in Zanjan province were evaluated in the two cropping years of 2017-2018 and 2018-2019 in the experimental farm of Zanjan University's Faculty of Agriculture. In both years of the experiment, improved cultivars such as Kimia, Sabz Koohin, Gachsaran, Maragheh and Bilehsavar were used as control cultivars. The first year, the experiment was conducted in the augmented design based on randomized complete bloke design with 200 lines. Each experimental unit consisted of one metere row. The distance between the rows was 25 cm, the distance on the rows was 5 cm, and the planting depth was 5 cm. At the beginning and end of each block, two rows of Sabz Koohin were planted as borders. The second year, Due to echeaving enough seeds from the first year, the experiment was carried out in square lattice design with tow replications and larger experimental units for the selected lines from the first year. Each experimental unit consisted of two one-meter rows. The distance between the rows, the distance on the rows and the planting depth were similar to the first year experiment. At the beginning and end of each incomplete blocks, two rows of Sabz Koohin were planted as borders. Results: In the first year, the results of analysis of variance showed that there is significant difference among lentil lines in terms of canopy temperature difference, podding period, number of seed per plant, seed yield per plant, harvest index per plant, number of seed per area, seed yield per area and 1000-seed weight at 0.01and 0.05 level. in this year, canopy temperature difference, podding period, first branch height, number of pod per plant, number of vacant pod per plant, number of seed per plant, seed yield per plant, harvest index per plant, number of seed per area, seed yield per area and 1000-seed weight had high value of genetic variation coefficient, heritability and genetic advance. lines 14, 68 and 165 were the superior lines in terms of phonological traits. The height of the plant and the height of the first pod in lines 85, 92, 193 and 195 were higher than other lines. Lines 32, 90 and 156 had the highest number of full pods. Lines 122, 163, 165 and 200 had the highest seed yield per plant. The 1000-seed weight in lines 163, 166, 171 and 174 was higher in compared with other lines. The highest seed yield was observed in lines 23, 150, 192 and 200. Finaly, based on the results of comparison of mean with superior control cultivar for each trait by LSD method and considering the degree of importance of traits, the 95 superior lentil lines from 200 examined lines were selected. In the second year, the results of analysis of variance indicated a significant variation among lentil lines in terms of all studied traits except for the first branch height at 0.01 and 0.05 levels. The canopy temperature difference, number of vacant pods per plant and number of seed per plant had high value of genetic variation coefficient. High heritability was observed in the days to 50% flowering, flowering period, days to 50% podding, days to 50% physiological maturity, seed filling period and straw yield per plant. The canopy temperature difference, flowering period, first pod height, number of vacant pod per plant, seed yield per plant, biomass per plant and straw yield per plant had high genetic advance. lines 150, 155, 173 and 176 were the superior lines in terms of phonological traits. The highest plant height and the highest height of the first pod was observed in lines 146 and 180 and lines 12, 47 and 130 respectively. Lines 1, 131 and 176 had the highest number of full pods. In terms of yield and yield components per plant, lines 1, 131 and 176 had the highest number of seeds and seed yield. The 1000-seed weight in lines 23, 52, 163 and 178 was higher in compared with other lines. In terms of yield and yield components, lines 55, 69, 86, and 176 were recognized as the superior lines. Finally, based on the results of comparison of mean lines with superior control cultivar for each trait by LSD method and considering the degree of importance of traits, the 44 superior lentil lines from 100 examined lines were selected. Conclusion: The evaluated lines were significantly different from each other in terms of most traits. High heritability was observed in the days to 50% flowering, flowering period, days to 50% podding, days to 50% physiological maturatry, seed filling period and straw yield per plant. Comparing to the control cultivars, the evaluated lines had a higher mean in most of the studied traits. Therefor by selecting superior lines in terms of yield potential and agromorphological traits this genetic potential can be used to create superior population and introduce high yield cultivars.

Journal of Crop Breeding, 2024

Introduction and Objectives: The evaluation of the genotype × environment interaction effect prov... more Introduction and Objectives: The evaluation of the genotype × environment interaction effect provides valuable information regarding the yield of plant cultivars in different environments and plays an important role in evaluating the stability of the yield of breeding cultivars. Genotype × environment interaction effect, especially in stressful environments, are important limiting factors in the introduction of new cultivars; therefore, it is very important to know the type and nature of the interaction effect and reach the verities that have the least role in creating interaction effects. Various methods have been introduced to evaluate the interaction effect, each of which examines the nature of the interaction effect from a specific point of view. The results of different methods may not be the same, but the best result is obtained when a genotype with different evaluation methods shows similar results in terms of stability. The purpose of this research was to evaluate the genotype × environment interaction effect in experiments conducted in different environments, to determine the relationships between genotypes and environments and to introduce the most stable red bean genotypes. Material and Methods: In this research, 14 red bean lines along with Yakut, Ofog and Dadfar control cultivars were cultivated in the form of a randomized complete block design with three replications in Khomein, Borujerd, Shahrekord and Zanjan research stations for 2 crop years under the same conditions. After combined variance analysis, according to the significance of genotype × environment interaction, AMMI and GGE-Biplot analysis methods were used to determine the compatibility and stability of genotypes. After AMMI Analysis, the stability parameters of AMMI were calculated. In addition to the AMMI stability parameters, the simultaneous selection index was also calculated for each of the indices, which was the sum of the rank of the genotypes based on each of the AMMI stability indices and the average seed yield rank of the genotypes in all environments. Results: The significance of the double and triple interaction effects of genotype with year and place (environment) in this study showed that genotypes showed different responses in different environments, and in other words, the difference between genotypes is not the same from one environment to another, and in these conditions, the stability of grain yield can be evaluated. The contribution of about 2.5 times the interaction effect of genotype × environment from the total sum of squares, compared to the effect of genotype, indicated the possibility of the existence of megaenvironmental groups in which some genotypes show their maximum performance potential in those environmental groups. Genotypes G12, G5 and G17 had the highest seed yield among the genotypes with yields of 3288, 3136 and 3111 kg per hectare, respectively. AMMI analysis showed that the first to seventh main components were significant at the 1% probability level, and despite the significance of all model components, the first and second main components had the largest contribution to the expression of genotype × environment interaction (66.5%). Based on AMMI1 biplot Genotypes G4, G5, G16, G17 and G12 had the highest values (positive and negative) of IPCA1. In contrast, genotypes G8, G3, G2, G7 and G11 had IPCA1 values close to zero. However, only the genotype G11 showed a performance higher than the average total yield and therefore it can be introduced as a stable genotype with high general compatibility. Based on AMMI2 biplot, genotypes G2, G7, G3 and to some extent G8 and G13 were introduced as stable genotypes, but only G13 genotype had a higher yield in all environments, so this genotype can be introduced as a stable genotype with good yield.; also, every two years, the same place under investigation had a high correlation with each other, so that Bro1 and Bro2 environments on the one hand and Kho1 and Kho2 environments and finally Zan1 and Zan2 showed a high positive correlation (the same effect) to create a mutual effect. In total of the simultaneous selection indices calculated based on AMMI analysis, genotypes G11, G17, G7, G13 and G12 were introduced as stable genotypes with high yield. GGE-Biplot analysis based on average yield and stability showed that genotypes G1, G2, G3, G8 and G7 had the highest general stability compared to other genotypes despite having the lowest yield. On the other hand, G12, G5 and G17 genotypes had the highest yield with less stability. No ideal environment was observed. But Kho1, Kho2 and Sha1 environments are closer to the ideal environment than other environments and they can be used to distinguish the studied genotypes to some extent. On the other hand, G12 genotype can be considered as a desirable genotype that has high average yield and high yield stability. In the same way, G17, G5 and G11 genotypes were in the next stage compared to the ideal genotype and to some extent they can also be considered as desirable genotypes. Conclusion: According to all the results, G12 genotype can be considered as a desirable genotype that has a high average yield and also has yield stability, and G17, G5 and G11 genotypes were in the next stage.

Journal of Crop Breeding, 2024

Introduction and Objectives: Oilseed rape is one of the most important sources of vegetable oil i... more Introduction and Objectives: Oilseed rape is one of the most important sources of vegetable oil in the world, and its seed contains more than 40% of oil, and the meal obtained from oil extraction has more than 35% of protein, and currently it ranks third among oil plants after soybean and oil palm. in the world. The existance of environmental stresses, such as drought stress, causes a significant decrease in oilseed rape yields. Therefore, breeding for drought tolerance is very important, and creating high yielding and early maturing or drought tolerant cultivars is one of the important goals of breeders. The purpose of this study was to determine the best general and specific combiners and the amount of heterosis compared to the superior parent in spring rapeseed using line×tester analysis in two conditions of normal irrigation and drought stress. Material and Methods: Seven high-yielding rapeseed lines were crossed with five testers with a range of early maturity in the 2018-2019. The first generation hybrids along with 12 parents (47 genotypes in total) were evaluated in the randomized complete block design with three replications in two conditions of normal irrigation and terminal drought stress (irrigation cut off at the beginning of podding stage) in the 2019-2020. The studied traits included physiological maturity date, plant height, number of pods per plant, pod length, number of grains per pod, height of the first pod from the ground, 1000-grain weight, seed yield, oil percentage and oil yield. Results: The results of analysis of variance in both normal irrigation and drought stress conditions showed a significant difference between hybrids for all investigated traits, which indicated a significant diversity between genotypes. In analyzing the effect of hybrids into the relevant components, the interaction effect of line × tester was significant for all the traits under normal irrigation conditions and also under drought stress conditions except for the height of the first pod from the ground, and oil yield. The effect of parents versus hybrids was significant in normal for all traits except the number of seeds per pod under normal irrigation conditions and except for plant height, pod length and number of seeds per pod in drought stress conditions, which indicates the existence of heterosis for these traits. For the trait of physiological maturing, among the lines, line 6 showed the highest negative general combining ability under normal irrigation and drought stress conditions, and tester 5 showed the highest negative general combining ability among the testers under normal irrigation and drought stress conditions. Tester 5 was contributed in early maturing T5×L3 hybrid under drought stress conditions. L1 and L5 in both conditions and T2, and L3 and L4 in normal irrigation conditions and T1 in drought stress conditions were identified as the best general positive and significant combiner for the number of pods per plant, and hybrids T5×L1, T1× L5, T2×L4, T4×L4, T1×L7, T1×L6, T2×L7, T3×L2, T5×L7, and T4×L3 were the best specific combiner to increase the number of pods per plant in both experiment conditions. T4 was the most significant positive general combiner under normal irrigation conditions and drought stress for the 1000-grain trait. Also, regarding the positive significant specific combining ability for this trait hybrids T2×L7, T3×L7 in both conditions, and in addition hybrids T1×L7 and T5×L4 under normal irrigation conditions and hybrids T1×L6 and T3×L5 under drought stress conditions showed the highest amount. The most significant positive general combining ability in grain yield was determined to T5 and L1 and L6 in both conditions. The best significant positive specific combining ability were T2×L7 and T3×L7 in both conditions. The highest positive and significant amount of general combining ability of the amount of oil, was given to T3 and T5 and L6 in both experimet conditions, and T4 and L7 in normal irrigation conditions and L5 in drought stress conditions. T1×L6, T5×L1, T2×L5, T3×L1, T5×L3 and T4×L4 were among the best hybrids in both conditions. In normal irrigation conditions, T2×L3, T4×L3, T5×L1, T4×L6, and T5×L3 and in drought stress, T5×L1, T2×L3, T2×L4, T4×L4, T4×L3, T4×L5 and T2×L7 had the highest amount of heterosis in the positive direction for the number of pods per plant. The trait of the number of grain per pods, T2×L3, T4×L3, T5×L1, and T2×L5 under normal irrigation conditions and T5×L6, T3×L6, and T5×L3 under drought stress condition had the highest amount of heterosis. Conclusion: The estimation of traits' combining ability showed that T5 and L1 and L6 were the best general combiners to increase grain yield. T3×L7 and T2×L7 hybrids were the best specific combiner for increasing grain yield under normal irrigation and drought stress conditions. Also for the 1000-seed trait, T3×L6, T4×L1, T5×L4 and T1×L1 hybrids under normal irrigation conditions and T3×L7, T1×L6, T2×L6 and T3×L3 hybrids under drought stress conditions have the highest amount of heterosis. The number of pods per plant and the number of grain per pods under normal irrigation conditions, T2×L3, T4×L3 and T5×L1 had significant positive heterosisTherefore, their parents can be suggested for hybrid varieties production programs.