玉米制种中三类苗的出现,将对制种纯度有很大的影响,而且也影响到产量和品质。因为三类苗在抽雄期间不可能与其它正常株同时进行,这样就会造成漏抽、或者抽时因株型过于瘦小而抽断雄穗,这些在田检抽雄后都会成为散粉株形成自交从而降低田间纯度。即使是抽雄时很仔细很干净、也 The emergence of three kinds of seed in corn seed production, will have a great impact on seed purity, but also affect the yield and quality. Because the three types of seedlings in the tasseling period can not be carried out simultaneously with other normal strains, which will result in leakage pumping, or pumping at the time due to plant type is too thin and spatter tassels, Thus reducing the field purity. Even when it is very carefully extracted tassels very clean, too