种植密度对不同玉米品种穗部性状及产量的影响

［目的］为研究一定生态条件下玉米高产的适宜种植密度。［方法］采用大田试验，以豫单998和郑单958玉米品种为对象，研究了不同种植密度对2个品种穗部性状及产量的影响。［结果］在试验密度范围内，郑单958的产量随密度的增加而增加；豫单998的产量开始随密度的增加而提高，当密度为67 500株/hm^2时，产量达最大（9 375.47 kg/hm^2），当种植密度为75 000株/hm^2时，产量反而下降。2个供试品种随着种植密度的增加，穗长、行粒数、穗粒重、千粒重均呈逐渐下降趋势；秃尖随密度的增加而增加；穗行数和穗粗无明显差异。［结论］不同玉米品种的耐密性有所差异，郑单958的适宜高产密度为75 000株/hm^2，豫单998的适宜高产种植密度为67 500株/hm^2。

Effect of Density on Yield and Spike Characters of Different Variety Maize

[Objective] The study aimed to provide the optimal planting density for hybrid yield under certain ecological conditions.[Method] The effects on spike characters and yield of maize were studied under 60 000,67 500 and 75 000 plants/hm2 by field test.[Result] The yield of the hybrid of Zhengdan 958,in a certain range,could increase by increasing plant density.For the hybrid of Yudan 998,the grain yield increased first and then decreased when density increased continuously.And increased plant density led to d...