玉米、棉花、大豆等喜温作物,在生长期内需多次进行中耕、追肥、开沟、培土等项田间管理作业。机组在田间往复运行中,由于多次转弯,不可避免地会碾压地块两头的幼苗,使保苗株数减少而造成减产。采用什么样的机械作业方法才能尽量减少幼苗损失呢?新疆生产建设兵团农二师29团场在七十年代初期,便开始实验四大圈播种、中耕机械作业法。据农业、农机技术人员在该团三个生产连队棉田实地调 Maize, cotton, soybeans and other thermophilic crops, in the growing period to be repeatedly cultivated, topdressing, ditching, earthwork and other field management operations. Reciprocating units in the field, due to multiple turns, will inevitably rolling two plots of seedlings, so that the number of seedlings to reduce the number of reduced production. In what kind of mechanical operation method can we minimize the seedling loss? Xinjiang Production and Construction Corps 29 division two farms in the early 1970s, began experimenting with four circles sowing, cultivating machinery operating law. According to agriculture, agricultural mechanics and technical personnel in the regiment of three production companies cotton fields on the tune