Studies on Genetic Variability, Heritability and Genetic Advance in Recombinant Inbred Lines of Wheat (Trticum aestivum L.)

The present investigation consisted twenty two heat tolerant Recombinant Inbred Lines (RILs) of wheat derived from crosses viz: AAI12 x K9162 and AAI12 x K8962. These heat tolerant lines along with two check varieties (NW 1017 and HD 2733) were raised during Rabi-2013-14 in RBD design. The mean sum of squares due to genotypes was significant for all the sixteen characters. The significant difference among the genotypes for all the characters under study suggested that there was ample scope for selection of promising Recombinant Inbred Lines (RILs) for yield improvement. Estimates of variability, heritability, genetic advance for sixteen quantitative and physiological characters. On the basis of per se performance for grain yieldper plant, genotypes RLW 3, 7, 13, 5 and 15 were found promising. The highest variability (VP and VG) was recorded for membrane stability (64.51, 54.64) plant height (48.08, 41.90), on an average. High estimates of heritability were recorded for all characters studied. High heritability along with moderate genetic advance was registered for plant height, grain filling period, grains per spike and test weight. Suggesting sufficient variability and thus scope for genetic improvement through selection for these traits. The higher magnitude of Genotypic coefficient of variation (GCV) and Phenotypic coefficient of variation (PCV) were recorded for canopy of temperature depressions, chlorophyll content, membrane stability suggesting sufficient variability and thus scope for genetic improvement through selecting for these traits. Relatively low magnitudinal difference was observed between GCV and PCV for all the traits studied. This indicated less environmental influence on the expression of all the attributes