Genetic Analysis of Yield and Mosaic Virus Resistance in Bitter Gourd (Momordica charantia L.) through Line × Tester Analysis

Abstract

An experiment was conducted to evaluate the genetic potential of bitter gourd genotypes and their hybrids for yield and mosaic virus resistance using a line × tester analysis. The study utilized six high-yielding lines (L1-L6) and three mosaic virus-tolerant testers (T1-T3) to generate 18 F1 hybrid combinations. These genotypes were evaluated for 19 traits, including yield components and biochemical markers associated with defense responses, such as Peroxidase (PER), Polyphenol Oxidase (PPO), and Phenylalanine Ammonia Lyase (PAL). The present study was undertaken to identify superior hybrids with high yield and resistance to mosaic complex viruses. Analysis of variance (ANOVA) revealed significant genetic variability among the parents and hybrids for most traits. The general combining ability (GCA) analysis identified lines L3 and L5 as superior for earliness and enzyme activity, while tester T3 was the best general combiner for both yield and biochemical resistance traits. Specific combining ability (SCA) analysis highlighted strong non-additive gene action, with several crosses exhibiting significant effects. Notably, the hybrids L5 × T2 and L3 × T3 demonstrated exceptional performance, combining high yield potential with enhanced resistance to the mosaic virus complex, as indicated by elevated biochemical marker expression. Conversely, some high-yielding crosses like L1 × T3 and L2 × T3 showed poor resistance, making them unsuitable for mosaic-prone environments. The study concludes that the hybrid combinations L5 × T2 and L3 × T3 are promising candidates for developing new bitter gourd varieties that are both high-yielding and tolerant to mosaic viruses.