玉米抗倒强度及其与植株性状相关性的初步研究

田间试验结果表明：玉米抗倒强度（D）品种间差异极显著，同一品种在灌浆的不同时期差异不显著；当D值超过25N／m时田间未出现倒伏，20—25N／m时出现少量倒伏，低于20N／m时出现严重倒伏。D与总拉力F、外拉力f和花后13天茎粗呈极显著正相关；与株高、穗位高、穗高系数、倒折率、重心高及花后13天的节长和株节数均呈极显著负相关，与穿刺力呈不显著或显著负相关；与植株鲜重呈正相关、与气生根层数和条数呈负相关但都不显著。抗倒强度的大小可以用来表示测交种及区试品种的抗倒折能力，是对玉米抗倒折能力的量化，在外界风力较小的情况下对判定玉米的抗倒性具有很好的参考价值。

Preliminary Study on Maize Lodging- Resistance Intensity and Its Correlations with Plant Traits

The results of field experiment showed that maize lodging -resistance intensity （D） was highly significantly different between different varieties, filling but not significantly different between different periods of stage in the same variety. There was no lodging phenomenon in field when the D value was more than 25 N/m, a few lodging phenomenon when it was 20 - 25 N/m, and serious lodging when it was lower than 20 N/m. The D value had highly significantly positive correlation with total pulling force F, outer pulling force f and stem diameter on the 13rd days after flowering. It had highly significantly negative correlation with plant height, ear height, ear height ratio, lodging index, height of gravity center and internode length and node number per plant 13 days after flowering. And there was not significantly or significantly negative correlation between D value and penetration force. The D value had positive correlation with plant fresh weight and negative correlation with ply and branch numbers of aerial root which were all not significant. The lodging - resist- ance intensity, as the quantification of lodging - resistance capacity, could be used to represent the lodging - resistance capacity of testcrosses and regional testing varieties, and had good reference value for the determination of maize lodging resistance when the wind was small.