在棉花良种繁育推广工作中存在着繁殖系数小,推广速度慢的问题。尤其在无霜期短的特早熟棉区,一个优良品种往往要经过4～5年的时间才能做到一次更换或更新。因而使良种不能及早的在生产中发挥它应有的作用。1979年开始在辽阳棉麻研究所等三个单位,进行了一粒点播地膜覆盖小面积对比试验。1980和1981两年扩大到六个繁种场(队)进行大面积的地膜繁种示范。经过三年的试验和示范,取得了较好的效果;为无 There is a problem of low propagation coefficient and slow promotion speed in the promotion of cotton seed breeding. Especially in the extremely early frost-free cotton area, a good variety often takes 4 to 5 years to be able to do a replacement or update. Thus, the good seed can not play its due role in the production as early as possible. Starting in 1979, Liaoyang Cotton and Linen Institute, and other three units, conducted a spot-film mulching small area comparative test. Expanded in 1980 and 1981 to six breeding fields (teams) for large-scale demonstration of mulching. After three years of experiment and demonstration, and achieved good results;