Studies on heterosis and combining ability through introgression in diploid cotton

摘要

Improvement in diploid cotton through introgression is an important tool. The well established stable varieties of diploid cotton were crossed with introgressed materials for better improvement in yield and to assess the heterosis and combining ability effects. The developed 18 diploid hybrids were evaluated alongwith line and testers. ANOVA revealed highly significant varietal differences for all the traits except boll weight, indicating sufficient variability among the genotypes in all traits except boll weight. The variances due to gca and sea were non-significant and gca : sea ratio indicated predominance to non-additive gene action for theses traits except boll weight. Among female parents, G. Cot-23 appeared good general combiner for seed cotton yield, number of sympodia per plant and number of bolls per plant. Whereas among males, AKA-01-3 was isolated as a good general combiner for ginning percentage, plant height and boll weight. The cross of a poor x poor parents G. Cot-17 x AKA-01-4 registered high per se performance, coupled with significant heterobeltiosis and sea effects in desired direction,, can be considered promising for commercial exploitation.