Nine bread wheat (Triticum aestivum L.) genotypes were crossed in a line × 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？× Rmada, A899？× Wifak, and A1135？× 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？× Wifak is a best specific combiner to reduce plant height, to increase 1000-kernel weight and number of grains per spike. AA × 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？× 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. , ？ low ratios and low to intermediate estimates of h2ns 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. 1. Introduction Bread wheat (Triticum aestivum L.) is an important staple food in Algeria. This crop ranks third after durum wheat (Triticum durum Desf.) and barley (Hordeum vulgare L.), with a yearly cropped area of 0.8 million hectares, representing 24.2% of the 3.3 million hectares devoted to small grain cereals. Algeria imported 3.0 million tons of bread wheat in 2010/2011, to remedy the decline in the domestic production and to build stocks to meet the needs. Increasing wheat production can be achieved by application of improved agronomic technics, developing and adopting high yielding varieties. Major emphasis, in breeding program, is put on the development of improved varieties with superior qualitative and quantitative traits and resilience to abiotic stresses. In fact, genetic improvement in bread wheat, having better tolerance against terminal heat and water stress, has a good promise to improve grain yield average and total wheat production. However to breed high
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