Cytoplasmic male sterile lines with desirable combining ability enhance the concentration of biochemical attributes and total yield in Capsicum annuum under temperature stress conditions

Abstract

The last couple of decades report showed that the chemical compounds (ascorbic acid, oleoresin, and capsaicin content) of chilli have a significant effect on human health, and increasing application of these important compounds especially oleoresin and capsaicin in various agro-food and pharmaceutical industries has resulted in their demand manifold. Hence, to fulfill the demands of industries, there is urgent need to identify wider adapted inbreds/ parental lines with significant combining ability effects to develop high yielding good quality hybrids with low seed cost. To address this, three newly developed cytoplasmic male sterile lines and 20 potential restorer lines were evaluated in a line × tester mating design to estimate combing ability for 15 plant growth, yield, and biochemical traits over three environments. Early season (low temperature condition, E1), main season (normal temperature condition, E2), and late season (high temperature condition, E3) constituted the three environments. The estimates due to general combining ability of lines, general combining ability of testers, and specific combining ability of crosses over environments were significant for all the traits evaluated, except due to general combining ability of lines for number of primary branches plant−1. In general, the magnitude of the additive variance (σ2A) was more than the non-additive variance (σ2D) except for number of primary branches plant−1 in E2, E3, and across the environments; and for plant height, plant spread, and number of fruits plant−1 in E3. The line CMS463D13A and the testers SL 475, IS 268, PP 402, FL 201, and C 142 were identified as potential parents to breed for high yielding good quality (ascorbic acid, oleoresin, capsaicin, and scoville heat units) genotypes suitable for early, main, and late season planting. Based on the specific combining ability estimates, promising crosses suitable for the respective crop seasons for fresh consumption and industrial purposes were identified. Across the environments, the cross CMS463D13A × IS 268 was promising for total yield plant−1, number of seed fruit−1, and capsaicin content. The cross involved good × good general combining ability parents and is a potential source to develop high yielding-pungent true breeding chilli lines.