The Effect of Defoliation at Seedling Stage on the Stem Lodging Resistance and Yield of Maize
[Objective]To study the effects of defoliation at seedling stage on lodging resistance and internode length characteristic of maize.[Method]A 2-year field experiment at two sites(Fengcheng and Zhangwu)was conducted to investigate the effect of defoliation at two seedling stage(5-leaf and 1-heart stage and 6-leaf and 1-heart stage)on the stem lodging resistance and yield of maize.[Result]Defoliation at seedling stage changed the morphological characteristics of maize plants,with similar patterns observed in Fengcheng and Zhangwu.Compared with the control group without defoliation,defoliationt at seedling stage reduced the number of stem nodes under the ear by 1-2 nodes,shortened the length of stem nodes below the ear position,but had no effect on the length of stem nodes above the ear position.The maize plant height and ear height decreased by 26-37 cm and 16-26 cm,respectively;Defoliation at seedling stage slightly improved the stem bending resistance of the 1-2 stem nodes at the base of maize,but had no significant effect on the stem puncture resistance and crush resistance;Defoliation at seedling stage had no significant effect on the root diameter and insertion angle of aerial roots,but the number and depth of aerial roots inserted into the soil slightly increased;The lodging rate of corn in Fengcheng was significantly higher than that in Zhangwu,and defoliation at seedling stage reduced the lodging rate of corn plants in Fengcheng by 14.8-23.4 percentage points.Defoliation at seedling stage reduced the corn vacancy rate,decreased the corn plant leaf area index,increased the sink source ratio,and delayed the corn growth period by 7-11 days.Grain yield of maize after defoliation at 5-leaf and 1-heart stage was increased by 9.54%-17.2%at Fengcheng and decreased by 5.75%-12.8%at 6-leaf and 1-heart stage at Zhangwu.[Conclusion]The results showed that defoliation at seedling stage increased maize yield especially for lodging-serious regions and reduced lodging percentage by improving crop lodging-related morphological and physiological traits.
Defoliation at seedlingMaizeLodgingStem nodesYield
万方数据
维普
