Heterosis and combining ability for yield attributes and quality traits in tomato (Solanum lycopersicum) under mid hill conditions of Himachal Pradesh

Abstract

The present investigation was undertaken to evaluate heterosis and combining ability among nine elite tomato (Solanum lycopersicum L.) genotypes and their 36 F₁ hybrids developed through a diallel mating design excluding reciprocals under mid-hill conditions of Himachal Pradesh during summer seasons of 2020 and 2021. The hybrids, along with parents and a commercial check hybrid, Naveen 2000+, were evaluated in a randomised block design with three replications for nine agronomic and quality traits. Significant heterosis over the better parent and standard check was observed for most of the characters studied. The crosses Arka Abha × H-7998 and Solan Lalima × BajT-4 exhibited desirable heterosis for earliness, whereas Solan Lalima × BajT-4, Solan Lalima × Arka Meghali and H-7998 × BajT-4 recorded superior performance for fruit yield/plant. The parents Solan Lalima and BajT-4 were identified as good general combiners for fruit yield and quality traits while BajT-4 also exhibited superior combining ability for number of fruits/plant, fruits/cluster and average fruit weight. High specific combining ability effects were observed in the crosses Solan Lalima × BajT-4, Solan Lalima × Arka Meghali and H-7998 × BajT-4 for fruit yield and associated traits. Predictability ratios less than unity for most traits indicated the predominance of non-additive gene action in the inheritance of these characters, suggesting the scope for exploitation of heterosis in tomato improvement programmes. The study identified promising parental combinations and hybrids for further evaluation under mid-hill conditions of Himachal Pradesh.