Evaluation of F4 Bread Wheat (Triticum aestivum l.) Genotypes for Genetic Variability, Heritability, Genetic Advance and Correlation Studies

Abstract

This research was carried out to check genetic variability, heritability and genetic advance in 11 F₄ bread wheat (Triticum aestivum L.) genotypes (10 F₄ lines and one check) in a randomized block design with three replications at the University of Agriculture Peshawar, Pakistan during 2015-16. Data was/were taken on parameters such as days to heading (days), plant height (cm), flag leaf area (cm²), spike length (cm), grain weight spike^-1 (g), 1000-grain weight (g), grain yield plant^-1 (g), biological yield plant^-1 (g)and harvest index (%). The statistically significant difference(s) was/were detected for the investigated traits.  The high magnitude of heritability (˃0.62) was noted for all parameters except spike length (0.57) which was moderate. Low expected genetic advance was recorded for days to heading (3.90%) and spike length (8.13%), moderate expected genetic advance was observed for plant height (9.95%), grain weight spike^-1 (11.54%) and 1000 grain weight (13.41%), while high expected genetic advance was noted for flag leaf area (24.72%), grain yield plant^-1 (20.45%), biological yield plant^-1 (23.64%) and harvest index (24%). Grain yield plant^-1 was non-significantly and positively correlated with days to heading (rG = 0.19^NS and rP = 0.07 ^NS),  plant height (rG = 0.30 ^NS and rP = 0.26 ^NS), flag leaf area (rG = 0.25 ^NS and rP = 0.18 ^NS), spike length (rG = 0.01 ^NS and rP = 0.07 ^NS), grain weight spike^-1 (rG = 0.28 ^NS and rP = 0.22 ^NS) and 1000-grain weight (rG = 0.02 ^NS and rP = 0.07 ^NS) at both genotypic and phenotypic levels. While significantly and positively correlated with biological yield plant^-1 (rG = 0.34* and rP = 0.33*) and harvest index (rG = 0.58** and rP = 0.66**) at both genotypic and phenotypic levels. High heritability showed that these traits are under genetic control and single plant selection could be started in F₅ generation. The strong correlation of grain yield plant^-1 with the mentioned traits showed that grain yield could be indirectly improved by improving these traits.