Rice yellow mottle sobemovirus is identified as the most destructive viral disease in lowland and upland rice. In this study, the mode of inheritance of resistance to a prevalent RYMV strain in Uganda was determined for resistant lines (upland NERICAs 8, 11, 12, 13 and Gigante (an O. sativa lowland variety) crossed with susceptible lines (lowland NERICAs 4, 6, 10 and IR64 (an O. sativa lowland variety)) in a full diallel mating design. Segregating F2 progeny were planted in field and screen house in -lattice design and inoculated by standard mechanical procedures. Reciprocal effects were...