1989年春在海南三亚基地我们用晚籼恢复系密阳46作母本与早籼恢复系测48—2作父本进行人工杂交，然后在其杂交后代中选择优良单株与V20A测交筛选，经过3年7代的选有选配，于1992年育成了杂交晚籼新组合威代644。该组合1994—1995年参加省区试，1997年2月通过湖南省农作物品种审 The spring of 1989 in Sanya, Hainan, we use the indica restorer line Moyang 46 as the female parent and early indica restore line 48-2 for the male parent of artificial crossbreeding, and then select their offspring in hybrids and V20A single cross test screening, After 3 years and 7 generations of optional matching, bred in 1992, a new hybrid combination of late Indica Vindy 644. The group participated in the provincial test in 1994-1995 and passed the trial of Hunan crop varieties in February 1997