夏玉米是河北省主要秋粮作物。气象条件是影响其产量的主要因素之一。在灌溉条件下,热量条件是主导影响因子。夏玉米各年间产量的较大波动虽然是由于年际间热量的较大差异所造成,但更直接的原因是不依据当地热量资源正确选择熟型和确定适宜播 Summer corn is the main autumn crop in Hebei Province. Meteorological conditions are one of the main factors affecting its production. Under irrigation conditions, the heat condition is the dominant factor. Although the large fluctuations of summer maize output during each year are caused by the large differences in the heat quantity between years, the more direct reason is that it is not based on the correct selection of cooked products and the proper sowing of appropriate heat resources