湘北地区采用油稻稻一年三熟制，季节矛盾特别突出，加上该地早春灾害性天气活动频繁，从而杂交早稻的引种与推广进度相当缓慢。据统计，临塔县自1985年推广杂交早稻以来，种植早杂最多的1991年，种植面积也只占早稻面积的35．3％，近年已滑坡至5％左右。据吨粮县的经验：杂交 In the northern part of Hunan Province, rice paddy was planted in three crops a year, with particularly prominent seasonal conflicts. In addition, due to the frequent early spring disastrous weather activities, the introduction and promotion of hybrid early rice was slow. According to statistics, since the early hybrid rice was popularized in 1985 in Linta County, the area with the largest number of early-season hybrids was planted in 1991, which accounted for only 35.3% of the area of ​​early rice. In recent years, the area has been slipping to about 5%. According to Tiangliang County experience: hybridization