Breeding cherry tomato grown under open field conditions for simultaneous improvement in yield, nutritional quality, and leaf curl virus disease tolerance

Abstract

ABSTRACTCherry tomato [Solanum lycopersicum var. cerasiforme (Dunnal) A. Gray] has the potential for improvement through heterosis breeding, which can be further utilized for the development of desirable recombinants. However, genetic control of yield, fruit quality, and disease severity traits are not well known. Six phenotypically diverse parents were crossed in half-diallel mating design to determine the extent of heterobeltiosis, mode of gene action, combining ability effects, and dominance effects for 18 quantitative traits to produce information that could lead to the development of improved genotypes. The predictability ratio indicated an overwhelming response of non-additive gene action in controlling the expression of most traits studied. Based on general combining ability effects, and average performance, genitors ‘16/TOCVAR-1ʹ and ‘16/TOCVAR-3ʹ could be potential donor parents in breeding. Based on average performance, heterosis manifested, and specific combining ability effects, crosses ‘16/TOCVAR-1 × 16/TOCVAR-3ʹ and ‘16/TOCVAR-1 × 16/TOCVAR-4ʹ were best in respect to yield, nutritional quality, and level of field tolerance against leaf curl virus disease under tropical and sub-tropical conditions. Partial- to over-dominance reactions for the inheritance of fruit yield, and other economically important traits, reflect the genetic basis of heterosis. Commercially exploitable cherry tomato hybrids with high antioxidant activity, tolerance to leaf curl virus disease, could be developed with the involvement of a single parent tolerant to this disease.