棉花从出苗到现蕾为苗期。黄河流域棉区一般历时40~45天。由于苗期是以营养生长为主,即长根、茎、叶为主的时期,棉花长势比较弱,抗逆能力差,且棉花苗期常伴有低温、干旱、病虫害等自然灾害,如管理不慎,容易导致棉田缺苗断茎,影响棉花的壮苗早发。所以棉花苗期应分类采取相应措施,即要预防低温冻害,又要防止高温烧苗,加强管理,及早查苗、补苗,千方百计保全苗、育壮苗促早发,为夺取全年棉花生产奠定丰产基础。主要应做好以下六方面工作: Cotton from emergence to budding for the seedling. The Yellow River basin generally lasted 40 to 45 days. As the seedling stage is mainly vegetative growth, that is, the roots, stems and leaves are the main period, the cotton grows weaker, the resilience is poor, and cotton seedling is often accompanied by low temperature, drought, pests and other natural disasters such as management Careless, easily lead to lack of cotton seedlings off stems, affecting cotton seedlings early onset. Therefore, cotton seedlings should be classified to take appropriate measures, that is, to prevent low-temperature frost damage, but also to prevent high temperature burning seedlings, strengthen management, and early check seedlings, make up for seedlings, try every possible means to preserve seedlings, seedlings promote early seedling to seize the annual cotton production lay High yield base. Mainly should do the following six aspects of work: