E.Munganyinka, R. Edema, J. Lamo, P. Gibson
Biotechnology research program, Rwanda Agriculture Board, Kigali, Rwanda
Makerere University, Kampala, Uganda
National Crops Resources Research Institute, Kampala, Uganda
Key words: Rice, Rice yellow mottle virus, Heritability, Segregating generation, Selection.
Heritability is the important genetic component in determining the effectiveness of selection in crop breeding program such as rice. A study was carried out at National Crops Resources Research Institute (NaCRRI) in Uganda to estimate heritability of resistance to Rice yellow mottle virus disease (RYMV) and of yield related traits. The parents and their F3, F4 and F5 segregating progenies were evaluated under field conditions. Recorded traits included yield, tiller number, days to flowering, days to maturity and yield per hill. It was found that heritability estimates computed through both variance components and parent offspring-regression methods were high for resistance to RYMV (Heritability= 68.7 to 98.1%) in F3, F4 and F5. These results indicated that the resistance to RYMV trait is heritable and under genetic control. Selection for resistance to RYMV in early generations could be effective. Furthermore, our results indicated that the studied yield related attributes are important and could be used for selection in rice breeding. Parental lines Nerica 11 and Nerica 12 were identified most suitable in breeding for resistance to RYMV while Nerica 8 and Nerica 13 could be used effectively in breeding for yield.