中文摘要：

【目的】机械粒收是玉米生产的发展方向,收获质量是影响其推广应用的主要因素。中国玉米机械粒收还处于起步阶段,目前在西北和东北等春播玉米区推广应用面积较大,黄淮海夏播玉米区正在积极开展试验示范。本研究通过分析黄淮海夏玉米机械粒收质量及其影响因素,为该技术的推广应用提供支持。【方法】2013—2015年累计选用了23个玉米品种,在黄淮海典型代表区河南新乡开展试验研究。2013年和2015年在收获期分别进行2次机械收获,2014年1次机械收获。收获当天测定各个品种的收获前籽粒含水率,并调查测产。机械收获后从机仓随机取一定量籽粒样品,立即测定收获后籽粒含水率,然后手工分拣样品,测定籽粒破碎率和杂质率;收获后,在田间选取3个代表性样区,调查落穗损失和落粒损失。【结果】2013—2015年,籽粒破碎率共调查131个样点,结果显示,收获时玉米籽粒含水率在20.80%—41.08%,籽粒破碎率变幅为4.98%—41.36%,籽粒破碎率随着籽粒含水率的提高明显升高;破碎率低于8%的有38个样点,占比29.01%,籽粒含水率低于26.92%时,收获的玉米籽粒能够满足破碎率8%以下的要求。机收杂质率共调查134个样点,杂质率0.37%—5.28%,杂质率低于3%的样点有107个,占比79.85%,杂质率也随着籽粒含水率的升高而增加;2013—2014年,籽粒含水率低于28.27%时,杂质率能够低于3%的国家标准;2015年收获时籽粒含水率虽然较高,但杂质率均在3%以下。田间损失率共调查108个样点,变幅为0.18%—2.85%（落穗率和落粒率）,均能满足国家标准,损失率不是影响机械收获质量的限制因素。在本试验条件下,籽粒含水率低于26.92%时,破碎率和杂质率分别低于8%和3%,田间损失率也符合国家标准,能够满足机械粒收质量要求。研究还发现,籽粒含水率相近的不同品种之间,机械收获的破碎率和杂质率也存在显著差异,?

英文摘要：

【Objective】Mechanical grain harvest is the developing direction of maize production,and harvest quality is the main factor affecting its popularization and application.This harvest way in China is still in the preliminary stage.The application areas are larger in the Northwest and Northeast China while experimental demonstration is just actively carried out in HuangHuai-Hai summer corn area.In this study,the influence factors on harvesting quality of mechanical grain harvest in summer maize were analyzed to provide supports for popularization and application of the technology.【Method】From 2013 to 2015,twenty three different maize cultivars were planted in Xinxiang,Henan.Twice harvests were conducted in 2013 and 2015 and once in 2014.The moisture content and yield were measured before harvest.When mechanical harvest was finished,kernel samples were taken out from the harvester to investigate the moisture content immediately.Then,the grain broken rate and the impurity rate were measured in laboratory by hand-picked method.The ear and kernel loss rates were investigated in the field sample areas after harvest.【Result】From 2013 to 2015,the results from 131 samples showed that corn kernel moisture content ranged from 20.80% to 41.08% and grain broken rate was between 4.98% and 41.36%.Grain broken rate increased with the rising grain moisture content.There were 38 samples that broken rate was below 8%,accounting for 29.01%.When kernel moisture content was under 26.92%,the broken rate could confirm to the standard of 8%.The results from 134 samples showed that the impurity rate was between 0.37% and 5.28%.There were 107 samples with impurity rate below 3% which accounted for 79.85%.The impurity rate also increased with the rising grain moisture content.From 2013 to 2014,the impurity rate did not meet the standard of 3% until grain moisture content was below 28.27% while the impurity rate was all below 3% with grain high moisture content in 2015.The loss rate from 108 samples ranged from 0.18% to 2.85% all of