棉花三类苗在生产实践中是一个较为笼统的概念。人们常常把植株矮小、生长缓慢的棉苗称为三类苗,而对三类苗的成因缺乏分析,在促使其转化时,一味强调施肥,不仅未能起到促进作用,反而适得其反。事实 Three kinds of cotton seedlings in the production practice is a more general concept. People often refer to the shortened and slow-growing cotton seedlings as the three types of seedlings. However, the lack of analysis of the causes of the three types of seedlings has not only promoted the transformation, but also failed to promote them. fact