Crossing Between Parents of Large Inter Parental Divergence with High General Combining Ability Increases Varietal Life

Crossing is the first and most important step for development of a variety. Around 1,562 crosses have been succeeded to develop rice inbred as a variety for mid and high hill regions of Nepal from 1975 to 2015. Among these crosses, only 15 varieties have been selected and released. We found parents of same genus with large inter parental divergence and high general combining ability (GCA) crossed inbred had longer varietal life with wide range of adaptation. The result implies that researchers should focus on divergent parents of high GCA for crossing so that the variety would have longer life with minimum genetic vulnerability and with reduced cost, labor and time.