机械粒收技术是西南玉米生产实现人工收获向籽粒收获跨越式发展的必由之路。本文基于2017年—2018年在西南4个省市开展的机械粒收试验,分析了当前西南玉米区机械粒收质量现状,探讨了影响粒收质量的主要因素。结果表明,籽粒破碎率和损失率高是当前西南玉米机械粒收面临的主要问题。西南玉米区机械粒收籽粒破碎率平均为7.41%,机收总损失率平均为5.84%,均高于≤5%的国标“玉米收获机械技术条件”(GBT-21961—2008)要求；杂质率平均为2.18%,低于≤3%的国标要求。收获时籽粒含水率分布范围14.40 %—57.54%,平均为26.66%。籽粒破碎率、杂质率与籽粒含水率显著正相关,而落穗损失率、总损失率与籽粒含水率极显著负相关。粒含水率降低有利于降低破碎率、杂质率,但籽粒含水率过低会导致落穗损失率和总损失率显著提高。玉米粒收质量存在区域、品种和机型间差异。四川夏玉米、四川春玉米、重庆春玉米、贵州春玉米和云南夏玉米破碎率平均值分别为6.23%、5.33%、5.56 %、11.26%和8.87%,落穗损失率平均值分别为6.00%、3.72%、5.91%、6.45%、3.47%、5.63%。同一机型相近籽粒含水率下粒收,参试品种国豪玉7号破碎率最高,杂质率最低；而损失率以延科288最高。不同机型对机械粒收质量的影响主要表现在破碎率、杂质率和落粒损失上,而不同机型间落穗损失率和总损失率的变异系数较小。针对不同玉米生产区域生态特点,开展适宜机械粒收品种、收获条件和粒收机具的研究,是推动玉米机械粒收技术的快速发展和应用的关键。
Mechanical grain harvesting is the way to realize the leap development from artificial harvest to grain harvest in southwest maize region. Based on the mechanical grain harvest experiments carried out in four provinces and cities in southwest China from 2017 to 2018, this paper analyzed the current quality of mechanical grain harvesting and the main factors that affected the grain harvest quality in southwest maize region. The results showed that, high grain breakage rate and loss rate were the main quality problems of maize mechanical harvesting in southwest China. The average grain breaken rate was 7.41%, and the average total grain loss rate was 5.84%. The grain breaken rate and total grain loss rate were both higher than the national standard of 5% [“Technical requirements for maize combine harvester" (GBT-21961-2008). The average impurity rate was 2.18% which was lower than the national standard of 3%. The distribution range of harvesting grain moisture content was from 14.40% to 57.54%, with an average of 26.66%. There was significant positive correlation between the grain breakage rate, impurity rate and the grain moisture content, while ear loss rate and total grain loss rate were significantly negative correlation with grain moisture content. Reducing the grain moisture content was beneficial to reduce the grain breakage rate and impurity rate, while it increased the ear loss rate and total grain loss rate. Mechanical grain harvesting quality of maize was different among regions, varieties and combine harvesters. The average broken rate of sichuan summer maize, sichuan spring maize, chongqing spring maize, guizhou spring maize and yunnan summer maize were 6.23%, 5.33%, 5.56%, 11.26% and 8.87%, while the average ear loss rate were 6.00%, 3.72%, 5.91%, 6.45%, 3.47% and 5.63%, respectively. Using the same combine harvest machinery with similar grain moisture content, variety Guohaoyu 7 had the highest grain breakage rate and impurity rate while the highest grain loss rate was invariety Yanke 288. There were significant differences in grain breakage rate, impurity rate and falling grain loss rate between different combine harvest machinery, while the variable coefficient of the ear loss rate and grain total loss rate was not significant. According to the ecological characteristics of maize production region, Carrying out the research on suitable varieties, harvesting conditions and grain harvesting machines were the key measurements to promote the rapid development and application of maize mechanical grain harvesting technology.