Unravelling the Genetic Complexity: Enhancing MYMV Resistance in Blackgram [Vigna mungo (L.) Hepper] Through Trait-based Selection

Background: Limited genetic diversity in blackgram, stemming from its common ancestry with greengram, presents challenges in combating Mungbean Yellow Mosaic Virus (MYMV), leading to yield stagnation. To address this, genetic screening and selection of segregating generations in F2 are essential for refining resistance traits with enhancing productivity. Methods: A two-season experiment was conducted in Panpoli, Tamil Nadu, during the Kharif 2021 and Kharif 2022 in a randomized block design using, F2 seeds from specific crosses (MDU 1 × Mash 114 and ADT 3 × PU 31), along with F1 and parent plants. MYMV disease scores were recorded using the infector row method for all the genotypes studied. Result: The study unveiled a complex genetic basis of MYMV resistance in blackgram, characterized by di-genic dominant genes displaying duplicative dominance type of epistatic interaction. This complexity underscores the insufficiency of simple selection methods. Estimates of genetic variability for “number of pods per plant” exhibited high genetic advance and moderate heritability, indicating control by additive genes. Positive correlations were observed between plant height, number of clusters per plant and number of pods per plant with yield. Path analysis revealed that traits like number of seeds per pod, 100 seed weight and number of pods per plant directly and positively influenced yield, which exhibit minimal influence from MYMV. These traits offer crucial selection criteria for enhancing MYMV resistance in blackgram.