北京地区玉米子粒脱水特性与适宜收获期研究

在北京地区采用9个供试品种设置春播和夏播试验,分析不同品种的子粒脱水动态,构建各品种子粒脱水模型,进而预测各品种适宜收获期。结果发现,北京地区至10月1日小麦正常播种期,郑单958、先玉335等9个春播玉米品种子粒含水率均能下降至25%以下,实现田间机械直收子粒,且春玉米播种具备较宽的窗口期。夏玉米6月15日常规播期种植条件下,至10月1日仅有早熟、脱水快的品种丰垦139和迪卡517子粒含水率可以勉强降至25%,其余7个供试品种子粒含水率下降至25%的时间分布于10月11日至11月1日,夏播玉米实现机械粒收会影响冬小麦的播种。因此,在北京地区,改冬小麦-夏玉米一年两熟制为春小麦-夏玉米(晚收)或春玉米-冬小麦-夏玉米(晚收)两年三熟制,选择适合玉米粒收的品种,可以实现春玉米和夏玉米的田间机械粒收,提高玉米种植效益。

Maize Grain Dehydration Characteristics and Suitable Harvest Time in Beijing Region

In 2018, we conducted spring and summer sowing experiments on nine maize cultivars and analyzed their grain dehydration trends during mature period in Beijing region of China. We further established a model of maize grain dehydration to predict the suitable harvest time of each cultivar. In Beijing region, before the date of normal wheat sowing(1st Oct), the grain moisture content of spring sowing maize such as ZD958, XY335 could drop below 25%, the standard of mechanical kernel harvest. And spring corn has a broad seeding time. For summer sowing maize(15^th June), only the grain moisture content of early-maturing or fast-dehydration cultivars such as Fengken139 and Dika517 could drop below 25% until 1st Oct. However, the grain moisture content of the other seven cultivars could not drop to 25% until 11^th Oct even 1^st Nov. Therefore, in the Beijing region, the double-crop (winter wheat-summer maize) rotation in one year should be changed into three-crop rotation within two years (spring wheat-summer maize rotation or spring maize-winter wheat-summer maize rotation). And selecting the cultivars suitable for kernel harvest can achieve the objective of employing mechanical kernel harvest for spring and summer maize, and then improve maize planting benefits.