Heterosis and combining ability in genetic male sterility based diploid cotton hybrids for yield, yield component, fibre quality characters and oil content

Sixteen genetic male sterility based diploid cotton hybrids along with parents and check were evaluated during Kharif 2012 at Cotton Research Station, Dr. PDKV, Akola to estimate the level of heterosis and combining ability. Among the lines GAK-8615 exhibited significant gca effect for more number of characters viz., days to 50% flowering, number sympodia per plant, number boll per plant and seed cotton yield per plant. Among the testers, AKA-7 exhibited significant gca effects for seed cotton yield per plant and 2.5% span length. The genetic male sterility based hybrids GAK-8615 x AKA-7 and GAK-8615 x AKA-0209 were found to be highly heterotic for seed cotton yield, number of bolls per plant and oil content. For fibre quality traits, hybrids (viz.,)GAK-423 x AKA-0209, GAK-423 x AKA-7, GAK-8615 x AKA-9703, GAK-423 x AKA-9009-1, GAK-423 x AKA-5 were found to be promising.