| Abstract: | Six intervarietal crosses involving two resistant and three susceptible genotypes of mungbean were attempted with the objectives to determine the mode of inheritance of gene‐specific Mungbean Yellow Mosaic Virus (MYMV) resistance. An infector row technique along with artificial inoculation was used for evaluating parents, F1, F2 and F3 plants for MYMV resistance. Disease scoring for MYMV indicated that F1s were highly susceptible as were the susceptible parents while resistant parent exhibited resistant reaction. The F2 progeny segregated in the ratio of 9 S:3 MS:3 MR:1 R suggesting that the resistance was governed by digenic recessive genes (rm1 and rm2). When one gene (rm1) was present in the homozygous recessive condition in different plants, it conferred moderately susceptible (MS) reaction, whereas when other gene (rm2) was in homozygous condition, moderately resistant (MR) reaction was obvious. When both genes (rm1 and rm2) were present together in the homozygous recessive condition, resistant reaction (R) was observed. The F2 segregation explained on the basis of phenotypic expression was further confirmed by F3 segregation. |
