Effect of Terminal Drought Stress on Morpho-Physiological and Yield Potential Traits of Bread Wheat Genotypes (original) (raw)
Related papers
2020
ABSTRACT: In order to identify genotypes tolerant to drought, this research was conducted on 12 bread wheat genotypes as split plot based on randomized complete blocks (CRBD) with 3 replication, in which the Main factor included irrigation treatments and sub factor was the genotypes being studied. The study was conducted at research farm of Islamic Azad University, Ardabil Branch Iran, in 2008-09 cropping years. Positively significant correlation (r = 0.512**) between yield under drought stress (Ys) and yield under normal humidity (Yp) was indicative of correlation between drought stress and irrigated conditions. Indices such as STI, TOL, SSI, MP, HARM and GMP and analysis into main components and Bi Plot were used to identify genotypes tolerant to drought. In total, first and second components accounted for 92.92% of the variations, and based on the coefficients of indices in first and second components, first component was designated as component of tolerance, whereas the second c...
In order to study the response of ten bread wheat genotypes to drought stress, two field experiments were conducted in a split plot design with randomized complete blocks (RCB) arrangement with three replications under irrigated and water stress conditions during two successive wheat growing seasons 2011/2012 and 2012/2013. The results of combined analysis of variance for grain yield over years indicated significant differences among main effects (years, water regimes and genotypes) and their interactions (P< 0.01). Based on the results obtained, statistical analysis revealed that grain yield significantly declined due to water deficit. The estimates of stress tolerance attributes indicated that the identification of drought-tolerant genotypes based on a single criterion was contradictory. Result of correlation analysis between grain yield in both conditions and calculated drought resistance indices revealed that stress tolerance index (STI), mean productivity (MP), geometric mean productivity (GMP), yield index (YI), harmonic mean (HM) and drought resistance index (DI) were the best indices for identifying high yielding genotypes in both conditions (drought tolerant genotypes). Therefore, these indices could be used successfully as selection criteria for the screening of genotypes for performance under various soil moisture levels. Screening drought tolerant genotypes using mean rank, standard deviation of ranks and rank sum (RS) distinguished genotypes, Cham 10, Sids 1, Cham 8 and Sahel 1 as the most droughts tolerant. Cluster analysis showed that the genotypes, based on indices tended to group into three groups: tolerant, semi-tolerant and sensitive genotypes. Principal component analysis (PCA), indicated that first and second components justified 99.87% of variations among drought tolerance criteria. Biplot analysis showed significant positive correlation between grain yield in the stress condition (Ys) with indicators STI, GMP, MP, YI, and HM, accordingly they are discriminating drought tolerant genotypes at the same manner. According to all different statistical procedures: Among all genotypes, Bohouth 4, L-R 67 and Sids 1 were identified as the genotype with high and stable yield in both conditions and Sids 1, Sham 10, Sham 8 and Sahel 1 were identified as the most drought tolerant to drought stress. Therefore, they are recommended to be used as parents for improvement of drought tolerance in bread wheat in hybridization programs.
RESPONSE OF SOME PROMISING BREAD WHEAT GENOTYPES TO DROUGHT STRESS
Egypt. J. Plant Breed., 2018
Eighteen bread wheat genotypes that included (thirteen lines from ICARDA, two promising lines from Desert Research Center (SU 1274 and SU 1109) and three local varieties from Agricultural Research Center (Giza 168, Sakha 93 and Gemeiza 10)were grown in two separate experiments; the first under rainfed conditions (stress) and the second was under rainfed in addition to two supplementary irrigations (adequate) at Maryout (North Western Coast of Egypt) during the two successive growing seasons 2013/2014 and 2014/2015, to evaluate these genotypes for drought tolerance. Mean squares due to irrigations (I) and genotypes (G) were significant for all traits studied across seasons, suggesting that all traits were markedly affected by drought stress and the presence of a wide range of differences among genotypes concerning all investigated traits. The variance due to interaction between genotypes and irrigations (G x I) was highly significant for all studied traits, except for number of spikelets/spike. It is clear that all traits increased significantly with adequate conditions compared with stress conditions. Concerning grain yield/plant (g) and straw yield/plant (g), 6068 (L4) recorded the highest values under stress and adequate conditions as well as the combined data. The most important relationships were between grain yield/plant and each of straw yield/plant, number of spikes/plant, number of spikelets/spike and number of grains/plant, indicating that such traits had a greatest influence on grain yield under respective stress environments. The genotypes 6068 (L4), SU 1109 (L15) and SU 1274 (L14) involved in the fourth cluster and positively correlated with yield and yield attributing traits and exhibited the highest values for stress tolerance index (STI), mean productivity (MP), geometric mean productivity (GMP), harmonic mean (HM), abiotic tolerance index (ATI), modified stress tolerance index for favorable conditions (K1 STI), modified stress tolerance index for stress conditions (K2 STI) and stress non-stress production index (SNPI) as well as grain yield under stress and adequate conditions. Therefore, they were considered the most tolerant and high-yielding genotypes under adequate and drought stress conditions. While the genotype 6094 (L8) displayed the lowest values of STI, MP, GMP, HM, ATI, K1 STI, K2 STI and SNPI as well as grain yield under stress and adequate conditions, therefore it was considered as sensitive genotype. Other genotypes were identified as semi-tolerant or semi-sensitive to drought stress. There was highly positive and significant correlation between grain yield under adequate conditions (Yp) and grain yield under stress (Ys). This indicates that high yield performance under adequate conditions resulted in relatively high yield under stress conditions. Both Ys and Yp were highly significant and positively correlated (P<0.01) with STI, TOL, MP, GMP, HM, YI, DI, ATI, SSPI, K1 STI, K2 STI and SNPI and negatively and significantly correlated with RDY, indicating that these criteria were more effective in identifying high yielding genotypes under different water conditions.
Evaluation of tolerant and susceptible bread wheat genotypes under drought stress conditions
2013
In order to identify genotypes tolerant to drought, this research was conducted on 12 bread wheat genotypes as split plot based on randomized complete blocks (CRBD) with 3 replication, in which the Main factor included irrigation treatments and sub factor was the genotypes being studied. The study was conducted at research farm of Islamic Azad University, Ardabil Branch Iran, in 2008-09 cropping years. Positively significant correlation (r = 0.512**) between yield under drought stress (Ys) and yield under normal humidity (Yp) was indicative of correlation between drought stress and irrigated conditions. Indices such as STI, TOL, SSI, MP, HARM and GMP and analysis into main components and Bi Plot were used to identify genotypes tolerant to drought. In total, first and second components accounted for 92.92% of the variations, and based on the coefficients of indices in first and second components, first component was designated as component of tolerance, whereas the second component w...
Turkish Journal Of Field Crops, 2014
The purpose of this study was to determine bread wheat genotypes with high yield potential and stability under controlled field conditions which resembled drought types exist in different plant growth stages in the Central Anatolia Region. This study was conducted using split-plot arrangement in randomized complete block design with four replications, the main plots were five drought treatments (D1: the general drought that represents the long term drought in region, D2:drought from the initiation of stem elongation to the initiation of heading stage, D3:drought from the initiation of heading to the end of flowering stage, D4:drought during grain filling period, D5: full irrigation) and ten bread wheat genotypes (
Post-anthesis drought stress is the most important problem affecting wheat production in dryland fields, specially in Mediterranean regions. The main objective of this research was to evaluate drought tolerance indices in dryland wheat genotypes under post-anthesis drought stress. The research was including two different experiments. In each experiment, twenty dryland bread wheat genotypes were sown in a randomized complete blocks design (RCBD) with three replications. One of experiments belonged to rain-fed conditions (post-anthesis drought stress) and other experiment was under non-stress conditions (with supplemental irrigation). Different drought tolerance indices include Stress Tolerance (Tol), Mean Productivity (MP), Geometric Mean Productivity (GMP), Stress Susceptibility Index (SSI), Stress Tolerance Index (STI), Harmonic Mean (HAM), Yield Index (YI) and Yield Stability Index (YSI) were evaluate based on grain yield under rain-fed (Ys) and supplemental irrigation (Yp) environments. G10 and G12 were the most tolerant genotypes based on TOL and SSI. But, based on MP, GMP, STI, HAM and YI indices, G1 and G2 were selected. STI, GMP and MP indices had high correlation with grain yield under rain-fed and supplementary irrigation conditions and were recognized as appropriate indices to identify genotypes with high grain yield and low sensitivity to drought stress environments.
Investigation of Drought Stress on Morphological Traits in Some Bread Wheat Cultivars
2013
In order to study the drought stress effects on wheat morphological traits, 20 bread wheat cultivars evaluated in two separate experiments in field conditions. A completely randomized complete blocks design with three replications was used. The results showed that there is a considerable variation between the understudying genotypes for the most traits such as height of the plant, length of the spike, length of the awn, the weight of the 100 kernel, length of the seed, length of the peduncle and the diameter of the seed. Factor analysis indicated that 4 factor explains more than 70 percent of data variance. Among them, the first factor by 29.1 percent had the more important effect. In stress condition path analysis showed that biological yield had the most direct effect (0.97) on the kernel yield. The most indirect effect by this trait was caused by the length of peduncle (0.30). For classification the genotypes, we used the cluster analyzing with the method on the base of the squar...
EVALUATION OF YIELD AND SOME MORPHOLOGICAL TRAITS OF WHEAT VARIETIES UNDER DROUGHT STRESS
International Journal of Plant, Animal and Environmental Sciences, 2014
Since the drought is known as one of the mostessential factor limiting growth and crop production, an experiment was carried out to evaluate the yield components of 15 bread wheat genotypes in a randomized complete block design with three replications in Islamic Azad University Research Farm of Ardabil in 2011-12. In this study, traits such as yield per ha, plant height, spike length, number of grains per spike and seed weight were studied. Analysis of variance indicated a significant difference among genotypes for all traits were evaluated. The overall mean yield in genotypes was 2427.1 kg ha in this study. Genotype 12 with 3125 kg ha produced the higher grain yield and genotype 9 had the lowest (1650 kg ha) than other genotypes.
2018
Drought and moisture stress is the most limiting factor affecting growth and productivity of crop plants.In order to study the response of ten bread wheat cultivars to drought stress, a field xperiment was conducted in 2013–2015 years at the the Agriculture and environmental research center of Ardabili, located at Moghan, Iran. The experimental design was a Split-plot xperiment based on randomized complete block design with three replications under five Drought stresses (no irrigation) regimes: rainfed (T1), the tillering stage (T2), at booting stage (T3), after anthesis (T4), full irrigation (T5) and 10 bread wheat cultivars. Combined analysis of variance revealed significant genotypic differences for Yp, STI, GMP, MP, TOL and HAM. Significant differences were also observed between drought treatments for Ys, STI, GMP, MP, TOL, HAM, SSI, YSI and DI. Nine drought tolerance indices including stress STI, SSI, TOL, HM, GMP, MP, YSI, DI) were calculated based on grain yield under drought...
Agriculture and Food, 2018
Drought stress is a main abiotic stress factor constraining wheat production in some years. Rainfall fluctuation during vegetative and generative growing periods causes grain yield reduction in Trakya Region, Turkey. This research was carried out in 2008-2009 and 2009-2010 growing years. Experiments were set up in a randomized completely blocks design in split-plot with three replications with 15 genotypes. The main plots were assigned for five moisture regimes, which included 3 drought stress environments (GS31-94, GS31-51 and GS51-94) one non-stress and non-treatment (control) environment. Droughts were created under mobile rain shelter at various plant growth stages from shooting up to maturating stage. Based on grain yield stress susceptible index (SSI), stress tolerance index (STI), tolerance index (TOL), mean productivity (MP), and geometric mean productivity (GMP) were calculated with their relation. The results of variance analyses for Yp, Ys and other drought tolerance indices indicated that genotypic differences were highly significant. Effect of drought stress on grain yield of all tested genotypes was different. Drought stress caused an average reduction of 59.9% on yield. Bereket was the highest yielding cultivar under fully drought stress condition. STI, MP and GMP showing the highest correlation coefficient with grain yield were the most desirable selection criteria for high yielding and drought tolerant genotypes. A positive and significant correlation was observed between Yp with TOL, MP, STI, GMP and HM, and negative correlation with YSI. These indices are the most suitable indices to screen genotypes in drought stress conditions.