种植密度对夏玉米基部节间性状与倒伏的影响

以玉米杂交种隆平206和凤玉906为供试材料,设60 000、75 000、90 000株/hm23个密度处理,研究不同种植密度条件下夏玉米基部节间相关性状和倒伏之间的关系。结果表明,隆平206生育后期植株倒伏率随密度增加而增大,凤玉906在低密度条件下倒伏率为0,其他2个密度条件下倒伏率均小于5%。随着种植密度的增加,玉米植株基部节间直径逐渐变小,茎粗系数减小,同时基部节间鲜重、干重逐渐减少,基部节间抗折力逐步降低,两个品种均表现出类似趋势。品种间比较,在同一密度处理下,虽然凤玉906基部节间抗折力显著低于隆平206,但茎秆基部节间干重显著高于隆平206,玉米茎秆基部节间干重对植株倒伏有重要影响。

Effects of Planting Density on Characteristics of Basal Internodes and Lodging in Summer Maize

Two maize hybrids, Longping206 and Fengyu906 were grown, to investigate the relationship between lodging and characteristics of basal internodes, a density experiment was designed with three levels of 60 000, 75 000 and 90 000 plants/ha. The results showed that the lodging rate increased significantly with increasing plant density in Longping206. The lodging rate of 60 000 plants/ha treatment was 0, and the lodging rates of 75 000 plants/ha and 90 000 plants/ha treatments were less than 5% in Fengyu906. With the increase of planting density, the stem diameter coefficient decreased significantly. Fresh weight, dry weight, diameter and the snapping resistance of basal internodes decreased gradually at the same time. Three basal internodes showed a similar trend in two hybrids. Under the same density treatment, the snapping resistance of basal internodes of Fengyu906 was significantly lower than that of Longping206. However, the dry weight of stem internodes of Fengyu906 was significantly higher than that of Longping206. The results suggested that the dry weight of basal internodes had great effect on the lodging of summer maize compared with other basal internodes characters.