种植密度对湘农玉13号生长发育和产量的影响

在长沙地区比较研究了玉米新品种湘农玉13号在不同栽培密度下的生长发育和产量形成特性。结果表明：在每公顷3.75万~6.75万株范围内,湘农玉13号产量随密度增大表现先增后降趋势,6.0万株条件下产量最高;随种植密度增加,果穗变短,行粒数显著减少,穗行数未受显著影响;叶面积指数随密度增加而显著增大,但叶片SPAD值变化不明显;在当年天气条件下,密度大于每公顷5.25万株时湘农玉13号倒伏率达到17%以上。因此,为获得高产,湘农玉13号在长沙地区的适宜密度为每公顷6.0万株,但需采取必要措施提高抗倒伏能力。

Effects of Planting Density on Growth and Yield of Xiangnongyu No.13,A New Maize Cultivar

The growth and development and yield formation properties of Xiangnongyu No.13,a new maize cultivar,were comparatively studied under different planting densities in Changsha region.The main results showed that kernel yield of Xiangnongyu No.13 showed a increase-decrease trend when densities changed from 37 500 to 67 500 plant/hm2,and the highest yield was gained under 60 000 plant/hm2.With the planting density increasing,the ear became shorter,the number of kernel per row was significantly decreased,while row number per ear had no significant change.With the density increasing,the LAI increased significantly while the SPAD value had no significant change.The lodging percentage of Xiangnongyu No.13 was over 17% when densities were higher than 52 500 plant/hm2.Therefore,to gain high yield,the suitable planting density of Xiangnongyu No.13 in Changsha was 60 000 plant/hm2,while some measures must be adopted to improve the lodging tolerance.