Heterosis and combining ability in small fruited ash gourd (Benincasa hispida)

Abstract

An attempt was made to develop small fruited ash gourd [Benincasa hispida (Thunb) Cogn] hybrids by crossing 10 genetically diverse ash gourd genotypes in a diallel mating system. The 45 F₁ hybrids along with their parents were evaluated for assessing their heterosis and combining ability for 11 important economic traits. The parent P₂ (Elevenchery local) was the best general combiner for fruit yield and fruits/plant. The specific combining ability component of variance (∂2s) was higher than general combining ability component of variance (∂2g) for the all the 11 characters studied which indicated the predominance of non-additive gene action in the improvement of these characters. The hybrids, viz. P₂ × P₇ (Elevenchery local × Chengamanad) which exhibited the highest heterosis over top parent (79.95 %) and highly significant sca effects for fruit yield, fruit length, flesh thickness, average fruit weight and days to first fruit harvest followed by P₃ × P₄ (Malappuram × IC 392313) which recorded the highest heterosis over better parent (166.38%) and highly significant sca effects for fruit yield, fruits/plant, flesh thickness and fruit length were found promising. Both the hybrids were small fruited with average fruit weight (2.04 kg) and (1.65 kg) respectively.