Inheritance of resistance to Mungbean Yellow Mosaic Virus (MYMV) in intra and inter-specific crosses of Vigna

The mode of inheritance of resistance to mungbean yellow mosaic virus (MYMV) in intra and inter-specific crosses of mungbean has been studied in the present investigation. An infector row technique was used for evaluating parents, F₁ and F₂ plants for MYMV resistance. No insecticide was sprayed in order to maintain the natural whitefly population in experimental field. In the field condition, only after 80% of plants showed MYMV incidence and the scoring of the test materials was done by MYMV disease reaction scale. According to the mean disease score, the mungbean genotypes were categorized into five groups resistant (R), moderately resistant (MR), moderately susceptible (MS), susceptible (S) and highly susceptible (HS). The results showed that in all the three intraspecific F₂ population segregated in 1: 3 (Resistance: Susceptible) ratio indicating single recessive gene whereas in case of all Interspecific crosses between mungbean and ricebean, segregation of F₂ population was in 3(R): 1(S) ratio which clearly indicates single dominant gene governs YMV resistance in ricebean.