Breeding chili pepper for simultaneous improvement in dry fruit yield, fruit quality and leaf curl virus disease tolerance

Abstract

ABSTRACT Enhanced productivity in dry chili pepper (Capsicum annuum L.), and improvement of fruit quality for industrial use in the export market, is a goal of plant breeders worldwide. Genotypes having a broad genetic background, and phenotypic diversity, were chosen as parents and crossed in a 6 × 6 diallel fashion without reciprocals to produce 15 F1 pepper hybrids to determine the mode of gene action, the extent of heterosis and dominance effect, and to estimate combining ability for quantitative traits. The predictability ratio exhibited a desired response for non-additive gene action in controlling expression of most traits including dry fruit yield per plant, but not for fruit length, fruit diameter, and capsaicin content which were controlled by additive and non-additive gene action, and dry fruit weight, percent disease index (PDI) of leaf curl virus controlled by additive gene effect. The maximum heterobeltiosis, in the desired direction, was for dry fruit yield per plant followed by a number of fruit per plant, fruit β-carotene content, PDI of chili leaf curl virus, and American Spice Trade Association (ASTA) color value. The good combiners cvs. Srinagar, Beldanga and BCCH Sel-4 were identified based on general combining ability effects and average performance. Hybrids ‘BCC-30 × G-4ʹand ‘BCCH Sel-4 × Beldanga’ were considered promising for value-added products and export based on average values, heterosis manifested, and relevance of specific combining ability effects. Testing is required to verify responses under field conditions. Promising hybrids could also be exploited in segregating generations to identify pure lines with desirable traits. Commercially exploitable chili hybrids tolerant to leaf curl virus disease could be developed with involvement of a single parent tolerant to this disease. Correlation indicated that selecting high yielding genotypes could have more contents of capsaicin, β-carotene, and ASTA color value in dry chili fruit. The outcome of the study for improved quality and productivity of dry chili will enable India and neighboring dry chili producing countries (China, Pakistan and Bangladesh) to increase exports of chilies and chili products, effectively meeting the competition from South American and African countries.