2019年在辽宁省铁岭市铁岭县蔡牛镇和2019、2020年在昌图县老城镇开展大田试验，探索辽北地区增加种植密度对玉米机械粒收质量的影响。结果表明：供试品种种植密度由6.0万株/hm2增加到7.5和9.0万株 /hm2，均表现出明显的增产趋势，其中最大增幅达15.11%。随着种植密度的增加，品种的生育期呈缩短、收获期子粒含水率呈下降趋势，其中子粒含水率下降幅度为0.1-2.6%。增加种植密度对收获子粒的破碎率、杂质率和损失率没有显著影响。由此可见，在辽北地区增加玉米种植密度不仅增产，而且能够降低收获期子粒水分、有利于机械粒收。

Field experiments were carried out in Cainiu and Laocheng Town, Tieling City, Liaoning Province, China, in 2019 and 2020, to explore the effect of increased planting density on mechanical maize grain harvesting in northern Liaoning province.The results showed that the yield had an obvious increasing trend with the maximum rate of 15.11% when the planting density of tested cultivars increased from 60,000 to 75,000 and 90,000 plants /hm2. Meanwhile, the grain moisture content of tested cultivars were declined by 0.1-2.6% during harvesting with their shortening growth period.Instead, the increase of planting density made little difference to grain’s impurity rate, broken rate and yield loss. Thus, It can be demonstrated that close planting is not only beneficial to maize yield, but also beneficial to mechanical grain harvest in northern Liaoning Province.

国家自然科学基金项目（面上项目，重点项目，重大项目）