“525”原代号为“72—5—25”,是我所从IR661中系统选育而成,1975年在荆门、江陵、武昌等地试验,亩产在1,057—1,215斤之间,比“691”增产4.7—11.9％,且早熟8—10天。1976年参加全省中秈良种区域试验,10个试点平均亩产1,087斤,居第一位。在扩大试种中,荆门县大新大队出现了成片的千斤四,新湖大队试种1.8亩,亩产达1,360斤。“525”因比“691”早熟、高产,更适宜于“肥-稻”、“麦-稻”、“油-稻”二熟栽培,近两年种植面积迅速扩大,现已遍及荆襄两地区及宜昌 “525” The original code for the “72-5-25”, is my system from the IR661 bred in 1975 in Jingmen, Jiangling, Wuchang and other places test, per mu in the 1,057-1,215 kg, than the “ 691 ”increase 4.7-11.9%, and premature 8-10 days. In 1976 to participate in the province of indica rice regional trial, 10 pilot average yield of 1,087 catties, ranking first. In expanding the trial planting, Jingmen Daxin Brigade emerged into a piece of jack-up, the new lake brigade trial planting 1.8 acres, 1,360 pounds per mu. “525” is more mature and productive than “691”, and is more suitable for the second maturity cultivation of “fat-rice”, “wheat-rice” and “oil-rice” and the planting area has expanded rapidly in recent two years. Area and Yichang