Heterosis and combining ability analysis for yield contributing traits and fibre quality in GMS based G.hirsutum L. x G.barbadense L. hybrids

Abstract

An experiment was carried out to evaluate the level of heterosis and combining ability in cotton. Thirty five interspecific hybrids were generated by crossing five lines viz., GMS 14, GMS 17, GMS 19, GMS 21 and GMS 27 with seven testers namely CCB26, CCB51, DB1901, CCB2, CCB6, CO18 and Suvin in line x tester mating fashion. Twelve parents along with 35 hybrids and a standard check (DCH 32) were raised in a randomized block design with two replications to evaluate the combining ability and heterosis to identify good combiners and the best hybrids with high yield and fibre quality. The lines viz., GMS 14 and GMS 17 and the testers viz., CO 18 and Suvin were found to record significant gca effects for yield and fibre quality traits. Out of the 35 hybrids, GMS 14 x CO18, GMS 27 x Suvin and GMS 17 x CO18 recorded highly positive significant sca effects for most of the traits. The ratio between additive and dominant genetic variance was less than one for all the traits, indicating the preponderance of dominant gene action or non-additive gene action. The above three crosses also exhibited high heterosis over mid parent, better parent and standard check. Hence, these hybrids could be harnessed after analyzing their performance in yield trials.

Keywords

• cotton
• combining ability
• heterosis
• high yield
• fibre quality.