在干旱和半干旱地区的棉田,采用三沟覆膜缝状保苗技术,可接蓄雨水、增墒保墒、减缓或推迟旱期,确保棉花苗全、早发、高产。所谓三沟覆膜,是指棉花播种时,进行平地覆膜,膜下有两个播种垄沟,背上一个施肥沟(如图1)。所谓缝状保苗,是指在先播种后覆膜时,在棉花出土2—3日内,在所选定的苗上方,用锋利的刀片将膜横拉个“一”形小口,把苗放出膜外。再在缝口处压上些湿土,把膜压 In the arid and semi-arid areas of cotton fields, the use of triple-trenched slit membrane seedling technology, can be connected with rainwater storage, moisture and soil moisture, slow or postponed drought period, to ensure that all cotton seedlings, early onset and high yield. The so-called trenches refers to the cotton planting, the flat film, the film has two sowing ditch, the back of a fertilizer ditch (Figure 1). The so-called slit seedlings, refers to the first sowing after the film, the cotton unearthed 2-3 days, the top of the selected seedlings, with a sharp blade to pull the film horizontal “a” small mouth, the release of seedlings membrane outer. Then pressure on the seam at some wet soil, the membrane pressure