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Exploitation of heterosis is one of the potential means for improvement of sweet pepper (Capsicum annuum var. grossum L.) that can further be utilized for identification of desirable recombinants. Promising hybrids could be acceptable to growers of tropical and subtropical climates if it is a high yielder with attractive fruit colour and blocky shape. Seven diverse parents were selected through multivariate analysis and were crossed in half diallel mating design to determine the extent of heterosis, mode of gene action, combining ability effects, and dominance estimates for 18 quantitative characters. Expression of fruit colour and shape at physiological maturity stage in the F1 generation indicated the dominance of red coloured group over other fruit colour groups and dominance of blocky fruit shape over elongate and round fruit shape. Preponderance of non-additive gene action for most of the characters under study suggested the usefulness of exploitation of hybrid vigour. Three genotypes, 8/4, C/4, and Baby Bell were found most promising donors. The hybrids, Arya×Baby Bell, 8/4×Baby Bell and C/4×8/4 were identified as promising based on per se performance, heterosis manifested, and relevance of specific combining ability effects, for possible commercialization under low cost protected structure of tropical and subtropical climates after critical testing. Partial to over dominance response in inheritance of most traits contributed to the genetic basis of heterosis. Isolation of pure lines from the segregating generation of heterotic hybrids emerged as a promising approach to develop line-bred variety having improved fruit yield and quality. [ABSTRACT FROM AUTHOR]

Recombination of commercially available hybrids could produce desirable segregants that act as sources of new alleles for tomato breeding. Seven commercial single cross (SC) hybrids of tomato (Solanum lycopersicum L.) were crossed in a half diallel fashion to obtain 21 double cross hybrids (DC) to estimate combining ability, mode of gene action and extent of heterobeltiosis for fruit yield, processing qualities and tomato leaf curl virus (ToLCV) disease severity traits. Predominance of non-additive gene action occurred in the control for all characters except for total soluble solids (TSS) content in fruit that was conditioned by both additive and non-additive gene action. Improvement of most traits in DC hybrids over SC hybrids occurred. Maximum heterotic effect in DC hybrids was for vitamin C content followed by lycopene content, fruit yield per plant, titratable acidity content, number of fruit per plant and percent disease index of ToLCV. Two good combiners, 'PAN-1286' and 'Devi' among SC hybrids were identified based on general combining ability effects and average performance. Commercial exploitation of DC hybrids, 'TO-1458 × L-37' and 'NS-501 × TO-1458' following multilocational testing in the tropics and subtropics might be useful. High yielding, ToLCV disease tolerant DC hybrids could be exploited in segregating generations to identify elite multi-parent advanced generation inter-cross (MAGIC) populations. [ABSTRACT FROM AUTHOR]