Line x tester mating design analysis for grain yield and yield related traits in bread wheat (Triticum aestivum L.).

摘要

Nine bread wheat (Triticum aestivum L.) genotypes were crossed in a line x tester mating design. The 20 F₁'s and their parents were evaluated in a randomized complete block design with three replications at the Field Crop Institute-Agricultural Experimental Station of Setif (Algeria) during the 2011/2012 cropping season. The results indicated that sufficient genetic variability was observed for all characters studied. A₈₉₉ x Rmada, A₈₉₉ x Wifak, and A₁₁₃₅ x Wifak hybrids had greater grain yield mean than the parents. A₉₀₁ line and the tester Wifak were good combiners for the number of grains per spike. MD is a good combiner for 1000-kernel weight and number of fertile tillers. HD₁₂₂₀ is a good general combiner to reduce plant height; Rmada is a good general combiner to shorten the duration of the vegetative growth period. A₉₀₁ x Wifak is a best specific combiner to reduce plant height, to increase 1000-kernel weight and number of grains per spike. AA x MD is a best specific combiner to reduce duration of the vegetative period, plant height and to increase the number of kernels per spike. A₈₉₉ x Wifak showed the highest heterosis for grain yield, accompanied with positive heterosis for the number of fertile tillers and spike length, and negative heterosis for 1000-kernel weight and the number of days to heading. sigma 2_gca/ sigma 2_sca, ( sigma 2_D/ sigma 2_A)1/2 low ratios and low to intermediate estimates of h2_ns supported the involvement of both additive and nonadditive gene effects. The preponderance of non-additive type of gene actions clearly indicated that selection of superior plants should be postponed to later generation.