GENETIC VARIATION, CORRELATION AND SELECTION INDICES IN ADVANCED BREEDING LINES OF RICE (Oryza sativa L.) (original) (raw)
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Journal of Plant Breeding and Crop Science, 2014
A study was conducted during 2008 to 2009 in 12 environments in Nigeria, Benin Republic and Togo to evaluate genetic variation and heritability of yield and related traits in 48 rice genotypes. The experiments were laid out in a randomized complete block design (RCBD) with three replications. Genotypes differed significantly at p > 0.001 for all the traits studied, which implies that the genotypes contain adequate genetic variability. Phenotypic coefficients of variation (PCV) were higher than genotypic coefficients of variation (GCV) in all the characters across the 12 environments. High heritability estimates were obtained for days to flowering (91.37), days to maturity (86.86), plant height at maturity, number of tiller per meter square, panicle shattering, panicle threshability, panicle per meter and panicle length (72.21) suggesting that the traits are primarily under genetic control. High estimates of heritability, GCV and genetic advance (GA) observed for grain yield is an indication that selection for grain yield could be achieved through phenotypic performance. Furthermore, high estimates of heritability, GA and GCV recorded in these characters could be explained by additive gene action. Low estimates of heritability, GCV and GA recorded for grain yield and number of grains per panicle could be due to non-additive gene effect suggesting that these traits were less responsive to specific environment influences. Grain yield recorded highly significant positive correlation with panicle length (0.28), leaf width (0.40), grain length (0.30), number of panicles per meter square (0.19) and1000-grain weight (0.17). It correlated negatively with basal leaf sheath coloration (-0.33) and grain width (-0.20) in the 12 environments. The current study indicated that more number of tillers, panicles per meter square, long panicles, high number of primary and secondary branch panicles and large 1000-grain weight are important yield related traits and could be used for selection in rice breeding programs.
Journal of the Bangladesh Agricultural University, 2019
The presence of sufficient genetic variability, the knowledge of nature of association among different characters and relative contribution of different characters to yield is a prerequisite to any breeding programme. The aim of the present study was to estimate genetic parameters of thirteen yield and yield attributing traits in 40 landraces of rice with a view to select better yield attributes in rice. The higher value of phenotypic coefficient of variation (PCV) compared to the corresponding genotypic coefficient of variation (GCV) for all the studied traits indicated that there was an influence of the environment. Number of unfilled grains per panicle exhibited high estimates of PCV and GCV followed by number of filled grains per panicle, number of grains per panicle, flag leaf area. High heritability coupled with high genetic advance was observed in flag leaf area, pollen fertility, number of grains per panicle and number of filled grains per panicle which reflected that the direct selection of these characters based on phenotypic expression by simple selection method for yield improvement would be more reliable. Grain yield per plant showed significant and positive association with days to 50% flowering, days to maturity, flag leaf area, number of total tillers per hill, number of effective tillers per hill, pollen fertility, number of grains per panicle, number of filled grains per panicle indicating selection of these characters for yield improvement may be rewarding. Both at phenotypic and genotypic level, days to 50% flowering, flag leaf area, number of effective tillers per hill, pollen fertility, panicle length, number of grains per panicle and 100 seed weight had direct positive effect on yield per plant indicating their importance during selection in yield improvement program. Moreover, the information generated from this study, can be exploited in future rice breeding program.
Phytopathology, 2020
The present investigation was carried out with thirty two genotypes of rice to study nature and magnitude of variability, degree of association between yield and its component traits and to assess direct and indirect effects of different characters on the grain yield. The analysis of variance revealed significant differences for the characters under study, indicating the presence of high genetic variability among the genotypes. The value of PCV was relatively higher than GCV values with small differences which indicate less environmental influence on the expression of all the traits. High heritability was recorded for all the traits studied. Filled grains per panicle and total grain per panicle exhibited highest heritability followed by plant height and unfilled grains per panicle. Positive and significant correlation was observed between unfilled grains per panicle and yield. In path coefficient analysis the traits like days to maturity, effective tillers, plant height, filled grai...
Pharma innovation, 2021
The present study was carried out at the Bagusala farm, M. S. Swaminathan School of Agriculture, Centurion University of Technology and Management, Paralakhemundi, Odisha in Rabi, 2020 with twenty one genotypes comprising nineteen traditional rice varieties and two checks to examine the nature of associations between yield and yield attributing characters. The characters association at both the genotypic and phenotypic level for grain yield per hill and its component characters revealed that the grain yield per hill exhibited highly significant positive phenotypic association with traits number of filled spikelets per panicle (0.675**), number of spikelets per panicle (0.72**), percentage of filled grain per panicle (0.09**), days to 50% flowering (0.495**), 1000-grain weight (0.493**), straw yield per hill (0.412**) and starch content (0.375**). The characters like plant height, flag leaf area, number of tillers per hill and protein content showed significant to highly significant negative association with grain yield per hill. Path coefficient analysis at phenotypic level showed that the character 1000-grain weight (0.538) exhibited highest positive direct effect on grain yield per plant followed by number of filled spikelets per panicle (0.420), protein content (0.327), number of spikelet per panicle (0.317), number of panicles per hill (0.127), straw yield per hill (0.094), number of tillers per hill (0.02), and days to 50% flowering (0.057). Therefore direct selection for these characters will be rewarding.
Nineteen promising rice genotypes were evaluated for variability, correlation and path analysis for yield and yield component traits. High genetic advance as per cent of mean was observed for plant height and grain yield per plant. High estimates of heritability were recorded for days to 50% flowering, plant height, panicle length, productive tillers per plant, spikelets per panicle, spikelet fertility and grain yield per plant. Character associations revealed a positive and significant association of grain yield with days to 50% flowering, plant height, panicle length, productive tillers per plant, the number of spikelets per panicle, spikelet fertility and test weight. Significant and positive association of plant height with panicle length and test weight; panicle length with spikelets per panicle and spikelets fertility; productive tillers per plant with spikelets per panicle, spikelets fertility and test weight; spikelets per panicle with spikelets fertility and test weight; spikelets fertility with test weight indicating a scope for simultaneous improvement of these traits through selection. The path analysis revealed a high positive direct effect of spikelet fertility, moderate positive direct effect of productive tillers per plant and spikelets per panicle in addition to significant and positive association with grain yield per plant. The productive tillers per plant had shown highest positive indirect effect via spikelet fertility on grain yield per plant. Plant height and productive tillers per plant recorded moderate to high PCV, GCV, heritability, genetic advance as per cent of mean in addition to correlation and direct effects of the trait with grain yield, indicating its effectiveness as important selection criteria for yield improvement.
The Pharma Innovation Journal, 2021
The present investigation entitled "Assessment of genetic variability and qualitative traits of Rice (Oryza sativa L.) germplasm for yield and yield attributing characters" was undertaken to evaluate 72 germplasm accessions along with three local checks in rice for yield and yield attributing characters in rice with row to row and plant to plant spacing 20×15 cm. The experiment was carried out to study the morphological characters, to access the genetic variability and to estimate the correlation coefficient among yield and ant its contributing traits in rice germplasm. The experiment was carried out at experimental area of rice in instructional farm, College of Agriculture, Rewa (M.P.) during kharif-2018. The experiment was laid out in Randomized Block Design with three replications. The analysis of variance revealed that highly significant variations were recorded among all the germplasm accessions for all the traits under study. It indicated that adequate amount of genetic variability were present in all studied characters. High estimates of phenotypic coefficient of variations (PCV%), genotypic coefficient of variations (GCV%) and high heritability coupled with high genetic advance as percentage of mean was recorded for were recorded for number of tillers per plant, number of productive tillers per plant, number of grains per panicle, biological yield per plant and grain yield per plant. These characters showed additive gene action in their expression. The grain yield per plant had significant positive correlation with biological yield per plant followed by harvest index, panicle length, number of tillers per plant, number of productive tillers per plant, seed index and number of grains per panicle. The grain yield also showed negative correlation with plant height, days to 50 percent flowering and days to maturity.
Physically hard working people prefer bold grained rice with good taste and qualities. But most of the modern high yielding varieties are medium and fine grained. The present experiment was conducted on 47 bold grained rice genotypes with two locally recommended high yielding check varieties namely Ranjit and Monohar Sali of Barak Valley, Assam to assess the genetic variability, correlation and coheritability for eight morpho-physiological characters. The characters were days to 50% flowering, plant height, flag leaf length, flag leaf breadth, effective branch tillers per hill, panicle length, sterility percentage and grain yield per hill. Very small difference between GCV and PCV was observed for the characters like days to 50% flowering and flag leaf breadth. Wide difference between GCV and PCV was observed for the characters like plant height, flag leaf length, effective branch tillers per hill, panicle length, sterility percentage and yield per plant. In the present investigation, high heritability associated with high genetic advance was found in the characters grain yield per hill and sterility percentage. These characters were predominantly governed by additive gene action. High heritability along with moderate genetic advance was observed in the character plant height. Moderate heritability associated with moderate genetic advance was recorded for the characters effective branch tillers per hill, flag leaf length and flag leaf breadth. Lastly, high heritability with low genetic advance was recorded for the character days to 50% flowering. This indicated that these characters were mostly governed by non-additive gene action (dominance and epistasis). The genotypic correlation coefficient was found to be higher than the corresponding phenotypic correlation coefficient. This indicates a strong inherent association among grain yield per plant and other morpho-physiological characters. The characters sterility percentage, effective branch tiller per hill and panicle length showed significant positive genotypic correlation with grain yield per hill. Sterility percentage, effective branch tiller per hill and panicle length had high coheritability with grain yield suggesting that selection for these characters would improve grain yield. Bold grained rice is preferred by the hard working people. Genetic yield enhancement of bold grained rice is a long term demand of the hard working class. Crop yield is a complex character which is dependent on many other characters. Yield responds very poorly to direct selection due to complex inheritance pattern. The present investigation was therefore, undertaken to obtain information on different genetic parameters namely GCV, PCV, heritability in broad sense coheritability, genotypic and phenotypic correlation of morphometric traits with grain yield. Such information could be used in formulating a successful rice breeding programme for genetic improvement of yield.
2022
Higher grain yield/production is the primary requirement to feed the fast growing population in the world, and the improvement of any trait mainly depends on magnitude of genetic variability present in base population. In this regard present investigation consists of 25 rice varieties and the experiment was conducted during Kharif 2020 and 2021 in Randomized Block Design with three replications. The data were recorded for 7 quantitative characters to study genetic variability, heritability, genetic advance and varieties performance. On the basis of mean performance, high seed yield per plant were exhibited by the varieties NDR-8002, CR Sugandha dhan-908, HUR-105, CR Sugandha dhan-910 and HUR-3022. Analysis of variance among 25 varieties showed significant difference for all characters studied. Highest genotypic coefficient of variation (GCV) & phenotypic coefficient variation (PCV) was observed for seed yield per plant that these characters could be used as selection for crop improvement. High evaluation of heritability was observed for traits days to 50% flowering, Plant height (cm), Number of tillers/plant, Panicle length (cm), Number of grains/panicle, Test weight (g) and yield/plant. High genetic advance were observed for number of traits days to 50% flowering, Plant height (cm), Number of tillers/plant, Panicle length (cm), Number of grains/panicle, Test weight (g) and yield/plant indicating predominance of additive gene effects and possibilities of effective selection for the improvement of these characters.
Estimation of genetic components of variability was done by taking into consideration twenty nine genotypes of rice collected from diverse locations. Analysis revealed that plant height exhibited high estimates of GCV and PCV preceded by number of tillers and effective tillers per plant, number of spikelets and number of grains per panicle and grain weight per panicle. Heritability was higher for days to 50% flowering followed by days to maturity, plant height and panicle length which suggested that these traits would respond to selection owing to their high genetic variability and transmissibility. High heritability coupled with high genetic advance as per cent of mean was recorded for number of spikelets and number of grains per panicle and grain weight per panicle. These characters indicate the predominance of additive gene effects in their expression and would respond to selection effectively as they are least influenced by environment.
The present investigation was conducted to estimate genetic parameters such as genotypic coefficient of variation (GCV), phenotypic coefficient of variation (PCV), heritability and genetic advance (GA) along with correlations and path coefficients from data collected on 83 rice genotypes. Analysis of variance indicated significant differences among the genotypes for different morphological characters. High GCV and PCV were observed for grain yield per plant, Panicle weight/plant, Biological yield/plant, Filled spikletes/plant, 1000 seed weight, Harvest index, Number of tillers/plant, where as moderate GCV and PCV was observed for Plant height. High heritability coupled with high genetic advance as percent of mean were observed for grain yield per plant, panicle weight/plant, biological yield/plant, filled spikletes/plant, harvest index, 1000 seed weight, number of tillers/plant, panicle length/plant, where as high heritability coupled with moderate genetic advance as percent of mean for days to 50% flowering and days to maturity. The filled spikletes/plant, harvest index, biological yield per plant showed high genetic advance that helped in effective and reliable selection through these characters for crop improvement. Grain yield per plant showed positive association with panicle weight/plant, biological yield/plant, number of tillers/plant and Harvest index, while, negative association with plant height. The biological yield per plant had maximum direct effect on grain yield/plant followed by panicle length/plant, harvest index, filled spikletes/plant, panicle length/plant and days to maturity. Hence, biological yield per plant, harvest index and number of seeds per plant are identified as key traits for developing high yielding genotypes of rice for future breeding programme.