棉花播种过迟,常因土壤水分不足,而延迟出苗,或出苗不全,并影响棉苗生育,不能充分利用生长期造成晚熟减产。但播种过早,土壤温度条件不够,种籽不能及时发芽,在土中时间过长,会减低发芽出苗能力,而造成缺苗、幼苗病重、棉株生长弱等不良后果。因此棉花播种要求适时,既要克服偏晚,也要避 Cotton sown too late, often due to lack of soil moisture, and delayed emergence, or inadequate emergence, and affect the cotton seedling growth, can not make full use of growth period late maturity and yield reduction. However, sowing too early, the soil temperature conditions are not enough, the seeds can not germinate in the soil for too long, will reduce the emergence of germination ability, resulting in lack of seedlings, seedlings sick, weak growth of cotton and other adverse consequences. Therefore, cotton planting requirements timely, it is necessary to overcome the late, but also to avoid