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A study was conducted for estimating genetic variability and characters association for eleven yield components using 169 genotypes (13 parents, 78 F 1 and 78 F 2 ) of bread wheat through half-diallel mating design during rabi season 2012-13 and 2013-14. The genetic variability, heritability in broad sense, genetic advance, correlation coefficients and path analysis were carried out for the assessment of genotypes through eleven yield component traits namely; days to 50% flowering, days to maturity, plant height, spike length, number of effective tillers per plant, number of grains per spikelet, number of grains per spike, 1000-grain weight, biological yield per plant, harvest index and grain yield per plant. Analysis of variance showed significant differences (at1% level of significance) for all the traits under study in both the generations (F 1 and F 2 ). The phenotypic coefficient of variation (PCV) and genotypic coefficient of variation (GCV) were high for plant height followed by number of effective tillers per plant, biological yield per plant, grain yield per plant, while high heritability coupled with high genetic advance were recorded for plant height and spike length in both F 1 and F 2 generations, respectively. Grain yield per plant was positively and significantly associated with number of effective tillers per plant, spike length, number of grains per spike, 1000-grain weight, biological yield per plant and harvest index while significantly but negatively associated with plant height. Path analysis revealed that the traits namely biological yield per plant, number of effective tillers per plant, number of grains per spike, plant height and harvest index exhibited positive direct effects on grain yield at both phenotypic and genotypic level in both generation (F 1 and F 2 ). These results, thereby suggests that yield improvement in breads wheats could be possible by emphasizing these traits while making selections in early generations.

Genetic analysis was conducted for grain yield and its component traits in a set of 13 bread wheat genotypes following a diallel (excluding reciprocals) mating design. The analysis of variance revealed highly significant differences in mean squares due to both general combining ability (GCA) and specific combining ability (SCA) for all the eleven traits in both F 1 and F 2 generations. This indicated involvement of both additive and non-additive gene action governing inheritance of traits. The σ 2 s was higher than σ 2 g and the ratio of σ 2 g/σ 2 s was less than unity (1.00) for all traits, suggesting the importance of non-additive gene action in both F 1 and F 2 generation. The parental genotypes NW 1014, PBW 343, PBW 502, DBW 14 and RAJ 3765 were found to be good combiners for multiple traits along with grain yield in both F 1 and F 2 generations. The seven crosses PBW 343 / K 8962, UP 2490 / CBW 38, PBW 343 / HI 1563, HP 1744 / UP 2425, HP 1744 / CBW 38, DBW 14 / CBW 38 and RAJ 3765 / UP 2490 were found to be good combiners for grain yield and its contributing multiple traits in both F 1 and F 2 generations and these crosses may be utilized in the development of high yielding progenies in bread wheat.

Genetic variability is the back bone of crop improvement programme, effectiveness of selection depends upon nature and magnitude of genetic variability present in the genetic material. The aim of the present study was that to identify the potential genotypes performing well under partially reclaimed saline- sodic soil (pH 8.6-8.9, EC = 4-4.2 dSm-1, ESP = > 15). Sixty four released varieties of barley collected from Directorate of Wheat Research, Karnal were grown during rabi season 2010-11, showing wide spectrum of variation for various characters. The characters studied were yield and yield contributing traits; namely plant height, days to maturity, fertile tillers / plant, length of main spike, grains per main spike, 1000-grains weight, grain yield per plant. The data on 7 characters was utilized for estimation of mean, range and least significant differences. The varieties RD-2552(8.52), HBL-276(8.35), RD- 2592(8.17), PL-419(8.15), Kedar(8.11), PL-751(8.10), JB-58(8.06), K-508(7.96) produced higher grain yield per plant and showed high to very high mean performance for several other yield component also. These selected varieties can be used in breeding program and can be recommended direct cultivation under partially reclaimed salinesodic soil.

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