Selection of bitter gourd (Momordica charantia L.) parental lines through line × tester analysis

The identification of genetically diverse and high-performing parental lines is critical for the development of superior bitter gourd ( Momordica charantia L.) hybrids. However, limited information is available on the combined morpho-genetic evaluation of inbred parental lines for targeted yield improvement under Bangladeshi conditions. To meet the increasing demand for bitter gourd, an experiment was conducted at the research field of Lal Teer Seed Limited, Gazipur, Bangladesh, to evaluate the suitability of twenty-seven morpho-genetically diverse inbred parental lines (IPLs) for the development of promising F₁ hybrids. Analysis of variance revealed highly significant differences ( P < 0.01) among the IPLs for all studied traits, indicating substantial genetic variability. The mean performance indicated that BT-1, BT-15, and BT-5 were superior for major yield-contributing traits. High heritability estimates were observed for fruit length, single fruit weight, and number of fruits plant − 1 (> 85%), indicating strong genetic control over the yield plant − 1 . Yield plant − 1 exhibited high heritability (88.32%) coupled with high genetic advance (> 50%), suggesting the effectiveness of selection. Line × tester analysis further confirmed significant genetic diversity among parental lines ( P < 0.01) for except days to the first female flower opening, with traits having high genetic coefficients of variation contributing to enhanced fruit size, weight, and fruit number. Based on multi-trait ranking and genetic parameters, BT-1 emerged as the best-performing parental line, exhibiting superior yield plant − 1 , single fruit weight, number of seeds fruit − 1 , 100-seed weight, early female flowering, and higher branch number. Overall, the study identified BT-1, BT-15, and BT-19 as promising parental candidates for developing high-yielding bitter gourd hybrids with improved fruit quality.