Selection for high yield and quality in half-diallel bread wheat F2 populations (Triticum aestivum L.) through heterosis and combining ability analysis

The study was carried out to evaluate the combining ability and heterosis of seven parents and their 21 half-diallel F2 populations for yield and quality traits during the 2013-14 season in the randomized complete block design with three replications. Significant differences were observed among the genotypes, GCA (general combining ability) and SCA (specific combining ability) effects for all traits, except spike length. The best combiner parents were identified as Esperia and Pehlivan for grain yield, and Flamura85, Aldane and Selimiye for quality traits because of significant GCA and per se performance. The ranges of best parent heterosis were -12.71 to 8.23% for plant height, -15.46 to 8.36% for spike length, -16.62 to 24.80% for number of grains per spike, -23.61 to 36.50% for grain weight per spike, -17.13 to 8.84% for harvest index and -44.26 to 15.83 for grain yield, -17.61 to 8.38% for thousand grain weight, -18.55 to 8.44% for wet gluten content, -33.80 to 24.78% for gluten index, -20.24 to 15.23% for Zeleny sedimentation value, -15.58 to 10.00% for quality index and -8.96 to 6.87 for grain protein content. The three (Slm/Phl, F85/Slm and F85/Esp) and seven (F85/Phl, Sb/Fs, Fs/Slm, Esp/Slm, Fs/Phl, Esp/Sb and Sb/Slm) of F2 populations are offered a good opportunity in base material for selection of potential because of significant SCA effects and best parent heterosis for grain yield and quality traits respectively.