Utility of gynoecious sex form in heterosis breeding of bitter gourd and genetics of associated vegetative and flowering traits

Abstract

This is the first report on discovering gene action in bitter gourd using gynoecious line as one parent in experimental design. Gene effects for yield and its contributing traits in bitter gourd were studied by involving 36 cross combinations obtained from crossing 9 diverse bitter gourd lines including one gynoecious line in halfdiallel fashion. The ratio between additive and dominance variance revealed the predominance of non-additive gene action for node to first female flower appearance, days to first female flower appearance, days from fruit setting to maturity, sex ratio and yield per plant. However, greater role of additive gene effects than dominance was evident for the characters like vine length. Heterosis over standard check (~Pusa Do Mousami) was also appreciable for all the traits under study. All the hybrids with gynoecious line (~DBGY-201) as one parent were heterotic for earliness as well for vine length in desirable direction. The hybrid, DBGY-201 × Priya was the best performer for yield, DBGY-201 × Arka Harit for sex ratio and NDBT-12 × Priya for days to fruit set from maturity. Highest yield was recorded in the parental line P1 (DBGY-201) followed by P2 (Pusa Do Mousami) and P3 (Pusa Vishesh). Gynoecious line was promising for its future use in heterosis and hybridization programme based on combining ability.