Evaluation of some breeding methods in durum wheat

Four breeding methods representing different cycles of phenotypic selection were evaluated using durum wheat (Triticum durum L.) crosses. This included ; 1) pedigree method (PM) with three cycles of selection in F3, F4 and F5, 2 ) modified bulk, (MB1) two cycles of selection in F4 and F5, 3) modified bulk2 (MB2) where only one cycle of selection in F3 was exercised, 4 ) bulk method (BM) where only natural breeding or selection was involved. This study was conducted at the farm of El-Giza Agric. Res. Station, ARC, Egypt, during four successive seasons from 2005/2006 through 2008/2009 to evaluate the efficiency of four different breeding methods in improving grain yield potentiality and some other agronomic traits in six durum wheat crosses. The lines derived from various selection cycles were evaluated in terms of number of spikes/plant, number of kernels/spike, 100-kernel weight and grain yield/plant. Results of analysis of variance for every cross showed significant differences among breeding methods in all crosses. Moreover, the genotypes showed significant differences in number of spikes/plant except crosses No. 1, 2 and 5, number of kernels/spike, except cross No. 1, 100-kernel weight except cross No. 2 and grain yield/plant for all crosses. The interaction between genotypes and methods of breeding was significant in all characteristics studied for all crosses except number of spikes/plant in cross No. 5, number of kernels/spike in cross No. 4, 100-kernel weight in crosses No. 1 and 6 and grain yield/plant for all crosses. Combined analysis for all methods of breeding crosses and genotypes showed significant differences for crosses (C), methods of breeding (M), genotypes (G), (C x M), (M x G) and (C x M x G). The best methods of breeding for all studied traits were pedigree method (PM) followed by modified bulk 2 (MP2) Results revealed that the six durum wheat crosses differed in all studied characteristics. Cross No. 5 had the highest number of spikes/plant, cross No. 2 had the highest number of kernels/spike, cross No. 3 had the highest 100-kernel weight and cross No. 5 the highest grain yield/plant