Genetics for seed traits and Mungbean yellow mosaic India virus reaction in urdbean (Vigna mungo L. Hepper)

Urdbean or blackgram is one of the important multi-season pulse crops grown in India. Improved seed quality and resistance to Mungbean yellow mosaic India virus (MYMIV) are the important objectives of the urdbean breeding program. For this, knowledge of inheritance for seed quality traits and MYMIV resistance is essentially required. Therefore, an attempt has been made to understand the inheritance of seed traits like seed luster, seed coat color, mosaic on seed surface, and MYMIV reaction using intra- and inter-specific bi-parental populations. The inheritance results revealed that in DPU88-31 × LBG-685 population, the shining seed registered dominance over the dull trait, while the green seed coat color exhibited dominance over the brown seed coat color. However, the inter-specific F₂ population derived from IPU11-02 × Pant M 6 deviated significantly from Mendelian ratios and supported severe segregation distortion for seed traits, while the mosaic on seed coat or mottling character studied in interspecific population demonstrated a dominant digenic inheritance pattern. In five inter- and intra-specific F₂ populations, MYMIV resistance demonstrated monogenic dominant inheritance, which was also validated in F₃ generations. Furthermore, linkage analysis exhibited an association between seed luster and seed coat color, while no association was noticed between seed traits and MYMIV resistance. The normality tests revealed that seed width and 100 seeds weight were controlled by a few major genes, while other quantitative traits were governed by many genes with small additive effects. The skewness suggested that complementary gene interactions were present among genes controlling 100 seed weight in the intra-specific cross, while duplicate gene interactions were involved in the inter-specific cross. The identified monogenic traits and linked morphological marker after further enrichment of the linkage group could be used as an important tool in the regular breeding program.