长江中游夏玉米成熟期茎秆力学特性及其影响因素研究

Mechanical Properties and Influencing Factors of Summer Maize Stem at Maturity Stage in the Middle Reaches of Yangtze River

本文对长江中游夏玉米生理成熟期前后茎秆力学特性及其影响因素进行了研究,以期为该地区夏玉米籽粒机械收获抗倒品种的选育及机械粒收时期提供理论依据。结果表明:同品种同密度同生长时期各节位的茎秆穿刺强度、抗折力呈第3节>第4节>第5节>第6节的规律;同品种同密度同节位的茎秆穿刺强度、抗折力随生长时间延长均呈逐渐减小趋势,不同年份趋势一致;同品种同生长时期同节位的茎秆穿刺强度、抗折力随密度增加呈不同变化,3个品种各具特点;在生理成熟期,品种、密度及年份均会影响各节位的茎秆穿刺强度和抗折力变化,且三者间存在互作效应,是影响茎秆穿刺强度和抗折力的因素。

The mechanical properties of stem and its influencing factors of summer maize before and after physiological maturity in the middle reaches of the Yangtze River were studied,in order to provide a theoretical basis for the selection of lodging resistant varieties and mechanical harvesting period of summer maize.The results showed that the puncture strength and breaking resistance of the stem of the same variety at the same density and the same growth period were in the order of internode 3>internode 4>internode 5>internode 6.The puncture strength and breaking resistance of stems of the same variety,density and internode decreased gradually with the growth time,and the trend was the same in different years.The puncture strength and breaking resistance of stem of the same variety at the same growth stage and internode showed different changes with the increase of density,and the three varieties had their own characteristics.At the physiological maturity stage,variety,density and year all affected the puncture strength and breaking resistance of stem at each internode,and there was interaction among the three factors,which were the factors affecting the puncture strength and breaking resistance of stem.