饲用玉米器官含水率、力学强度与籽粒机收质量的关系研究  

Role of grain crushing resistance and grain threshing characteristics in determining suitability of feed maize cultivars for machine harvesting and effect of plant moisture content

作　　者：雷恩[1,2] 邵迪 朱天彪 舒星 杨永兵 王岳东 唐启源[1] LEI En;SHAO Di;ZHU Tian-biao;SHU Xing;YANG Yong-bing;WANG Yue-dong;TANG Qi-yuan(College of Agronomy, Hunan Agricultural University, Changsha 410128, China;College of Life Science and Technology, Honghe University, Mengzi 661199, China;Agricultural Maechinery Research Institute of Yunnan Honghe Hani and Yi Autonomous Prefecture, Mengzi 661100, China)

机构地区：[1]湖南农业大学农学院,湖南长沙410128 [2]红河学院生命科学与技术学院,云南蒙自661199 [3]云南省红河哈尼族彝族自治州农业机械研究所,云南蒙自661100

出　　处：《草业学报》2020年第9期125-135,共11页Acta Prataculturae Sinica

基　　金：国家重点研发计划项目(2016YFD030030705);红河学院中青年学术带头人后备人才基金(2016HB0402)资助。

摘　　要：在玉米正常收获期间,明确器官含水率、力学强度和机收质量的变化规律,探明影响籽粒机收效果的直接因素,对实现玉米籽粒机收和提升机收质量具有重要意义。本试验以两个不同熟性品种为材料,采用半喂入式籽粒收割机,开展分期收获的田间试验研究。结果表明,籽粒静态压碎强度(耐破碎性)和籽粒与穗轴连接强度(易脱粒性)分别与籽粒破碎率形成了直接的因果关系,两者同是影响破碎率的关键因素。籽粒压碎强度(x)与破碎率(y)可高度拟合为二项式回归关系(R^2=0.8827,P<0.001),回归方程为=0.0021x^2-1.5443x+293.78,籽粒和穗轴连接强度(x)与破碎率(y)可高度拟合为幂函数型回归关系(R^2=0.7656,P<0.001),回归方程为=0.007x^4.12,而穗轴弯折强度与破碎率之间的关系小于上述(R^2=0.1644,0.01<P<0.05)。在玉米收获后期,虽然早熟品种‘金玉99’的籽粒与穗轴连接强度明显小于晚熟品种‘宝玉9号’,但是‘宝玉9号’的籽粒压碎强度却显著大于‘金玉99’,最终导致两品种的籽粒破碎率差异不显著(P>0.05)。落地籽粒损失率除了与植株倒伏倒折有关以外,对刀式割台容易在果穗脱粒前产生落地籽粒损失,并且越容易脱粒的籽粒损失越大,籽粒含杂率总体上随杂质器官含水率的下降而显著降低。适宜籽粒机收的玉米品种应具备的主要特征是茎秆坚韧抗倒伏、籽粒坚硬易脱粒。This research studied the role of selected mechanical properties of grain and cob(in particular grain crushing resistance and the detachment resistance of grain on the cob)and plant and cob moisture content in determining suitability for machine harvesting in feed maize.This information is important for improving harvest outcomes for feed maize crops in Southwest China.An early and a late maturing cultivar were tested.The experiment involved a mechanical harvester and a large field study.It was found that the grain crushing resistance(CR,force required to crush grains)and detachment resistance(DR,force required to detach grains from the cob)directly affected the percentage of broken grain(%BG).The relationship between%BG and CR could be described by the quadratic regression relationship:%BG=0.0021CR^2-1.5443CR+293.78(R^2=0.8827,P<0.001),and the relationship between%BG and DR by a power regression relationship:%BG=0.007DR4.12(R^2=0.7656,P<0.001).The relationship between%BG and crushing resistance of the cobs was much lower than the aforementioned(R^2=0.1644,0.01<P<0.05).In the later stages of maturation,although the DR of early maturing cultivar‘JY99’was significantly lower than that of late maturing cultivar‘BY9’,the grain crushing strength of‘BY9’was significantly higher than that of‘JY99’,so that these two factors cancelled each other,leading to there being no significant difference in%BG between the two cultivars.In addition to these relationships there was also an association between plant lodging and grain loss;the stripper rotor of the header harvester readily caused grain loss before ear threshing.Further,the grain loss was greater when grains were easy to thresh.Overall,grain impurity rate significantly declined as the water content of the non grain organs reduced.A maize cultivar suitable for mechanical grain harvesting should possess specific characteristics,including tough stalks that are resistant to lodging,with grains that are hard and easily detachable.

关 键 词：玉米 机械粒收 器官含水率 力学强度 籽粒破碎率 

分 类 号：S51[农业科学—作物学]