河北省中南部是小麦、玉米一年两熟的粮食基地。夏玉米的传统播种方式是在麦收前钻在麦垄里人工刨坑点播。此种方法的好处:一是提前七八天下种,延长玉米生长期,有利于增产;二是缓解麦收时节又收又种的劳力紧张程度。近几年来,随着小麦联合收割机的广泛应用,小麦收获时,人工点种的玉米幼苗伤害率很高(有的高达10%以上),再加上高产小麦 Central and southern Hebei Province is a wheat, corn cooked twice a year in the food base. Summer corn sowing is the traditional method of planting before the wheat harvest in the artificial ridge mow pit on-demand. The benefits of this method: First, seven or eight days in advance under the species, to extend the growth of maize, is conducive to increasing production; second is to alleviate the wheat harvest season and the tension of the labor force. In recent years, with the widespread use of wheat combine harvesters, artificially spotted corn seedlings have a high rate of injury (some as high as 10% or more) at harvest, coupled with high yield of wheat