Evaluation of quantitative traits distribution in F2 backcross population of purple wingedbean [Psophocarpus tetragonolobus (L.) DC] and its application in selection

Abstract

Wingedbean [Psophocarpus tetragonolobus (L.) DC] is a nutritious legume vegetable with high potential for food diversification in Indonesia, yet its cultivation remains limited due to late maturity and unstable yield. Information on the distribution of quantitative traits, heritability, and genetic advance in segregating populations is essential to determine effective selection criteria in breeding programs. This study evaluated the distribution patterns, heritability, expected genetic advance, and selection limits of quantitative traits in a BC₁F₂ population of purple wingedbean. BC₁F₂ backcross population generated through selfing of BC₁ plants originating from the cross between F₁ (PLB 2.3 × MDM 1.2) and the recurrent parent MDM 1.2. Total of 161 plants were observed for quantitative traits, including flowering time, harvest age, yield components, and pod characteristics. Normality was tested using the Kolmogorov–Smirnov method, followed by skewness and kurtosis analysis for non-normally distributed traits. Results showed that only pod length and fresh pod weight per pod were normally distributed, while the remaining traits deviated from normal distribution, indicating segregation effects and possible influence of major genes, epistatic interactions, and environmental variation. Most traits exhibited high broad-sense heritability and high expected genetic advance, particularly number of flowers per plant, number of fresh pods, pod length, and pod weight per plant, suggesting good prospects for improvement through selection. Selection based on multiple yield-related traits identified several superior individuals with higher yield potential. These traits are recommended as effective selection criteria for developing early-maturing and high-yielding purple wingedbean varieties in subsequent generations.