在确定棉花播种适期时,温度这一因子起着决定性的作用。在平均温度相同的不同棉区,由于日温差大小的变化不同,在棉花播种期早晚、棉苗出土快慢程度上亦有所差异。即使在同一地区,在相同的气候条件下,因为棉种与棉花品种不同,虽然同时播种,但出苗早晚与生育的快慢也是不同的。为了探求不同棉种和早、中、晚熟品种类型发芽时所要求的温 In determining the cotton sowing period, the temperature of this factor plays a decisive role. In different cotton areas with the same average temperature, due to the different changes of the daily temperature difference, the speed of the cotton seedlings unearthed in the morning and evening are different. Even in the same area, under the same climatic conditions, cotton varieties and cotton varieties because of different, although sowing at the same time, but the emergence of morning and evening emergence and growth are also different. In order to explore different varieties of cotton and early, middle and late varieties of germination required temperature