COMPARISON OF BREAD WHEAT LINES SELECTED BY DOUBLED HAPLOID, SINGLE-SEED DESCENT AND PEDIGREE SELECTION METHODS

Yield performance of each group of ten spring bread wheat lines select ed by doubled haploid (DH), single-seed descent (SSD) and pedigree sel ection (PS) methods from three F-1 crosses was compared with the aim o f evaluating the DH method in breeding programs. Populations of 65-97 DH lines and 110 SSD lines per cross were used for selection. PS lines were developed by repeated selections from 1500 F-2 plants. Yield eva luation was performed at the Fg generation of SSD and PS lines along w ith DH lines in a 2-year field experiment. It took only 2 years from t he planting of wheat materials for DH production to the planting of se lected DH lines for yield evaluation. There was no significant differe nce in grain yield between DH lines and PS lines selected from an F-1 cross whose parental varieties were closely related in their pedigrees , In two crosses with low coefficients of parentage and a large variat ion in their progenies, grain yield of selected DH lines was significa ntly lower than those of selected SSD and PS lines. These results conf irm that the DH method can save time in obtaining recombinant inbred l ines ready for yield evaluation. However, a larger DH population is re quired to achieve the same level of genetic advance with the PS method in crosses containing greater genetic variation.