晚播对春玉米倒伏及茎秆力学特性的影响

Analysis of Lodging and Mechanical Properties Characterization of Spring Maize under Late Sowing Dates

以玉米为研究对象,通过调查晚播春玉米倒伏发生类型、程度,同时测定与倒伏密切相关的性状。结果显示:晚播条件下,春玉米倒伏率显著增加,茎倒伏(SL)率高于根倒伏率;茎秆第2-7节间是茎折的主要发生部位,其中第3、4节间最为严重;晚播玉米株高显著降低(p<0.05,下同),穗位高和穗高系数显著增加;晚播玉米第2-4节间直径显著降低而长度显著升高,同时其惯性矩和抗弯截面系数显著低于适期播种玉米。

The sowing date influences lodging resistance of maize. This paper described the types,degree and the mechanisms of lodging under late sowing dates. A field experiment was conducted to investigate the lodging types,degree of lodging and morphology and mechanical properties in the internodes of spring maize under late sowing dates. The results showed that compared with the maize of non-late sowing dates,lodging was severe under late sowing dates. Stem loading was the most affected type. The main breaking sites of stem lodging was from second node to seventh node,especially in third and fourth node. The plant height was significantly reduced( p <0. 05,the same below),while the height of ear and the spike position height coefficient was significantly greater. The diameter in the second,third and fourth bending node was significantly lower,while the length of second,third and fourth node was significantly greater.