Unlocking genetic potential, trait associations, and molecular confirmation of bacterial wilt resistance in bell...

Bell pepper is a valuable vegetable crop from an economic perspective but is highly susceptible to biotic and abiotic stresses, particularly bacterial wilt, which severely limits its productivity. Breeding for high yield and bacterial wilt resistance is therefore essential. This study aimed to assess 24 bell pepper genotypes for genetic variability, trait associations, and their potential for improving marketable fruit yield and to identify superior bacterial wilt-resistant genotypes.

The analysis of variance (ANOVA) showed significant genetic variability among the evaluated genotypes across all traits studied. Among them, genotype G₁₄ (BWT-39-DR) recorded the maximum marketable fruit yield, with G₁₃ (BWT-39), G₁₅ (BWT-39-BR), G₁₇ (Kandaghat Selection), and G₄ (BWT-3Y-4L), also demonstrating strong performance in traits such as days to first picking, harvest duration, average fruit weight, marketable fruits per plant, and quality attributes. Bacterial wilt resistance was tested under sick field conditions and confirmed using the SSR marker CAMS451. High phenotypic and genotypic variation, heritability, and genetic advance were observed for fruit shape index, marketable fruits per plant, and marketable fruit yield per plant. Marketable fruit yield per plant showed a strong positive correlation with marketable fruits per plant, harvest duration, capsanthin content, ascorbic acid content, average fruit weight, and primary branches per plant. Marketable fruits per plant and average fruit weight were key selection indices for yield improvement.

The identified genotypes BWT-39-DR, BWT-39, BWT-39-BR, Kandaghat Selection, and BWT-3Y-4L are recommended for multi-location testing and hybridisation programmes to develop high-yielding, bacterial wilt-resistant bell pepper varieties.