砂姜黑土区小麦玉米秸秆全量还田对玉米抗倒性能的影响

 【目的】探讨砂姜黑土区小麦玉米秸秆全量还田对夏玉米抗倒性能的影响。【方法】以夏玉米品种郑单958为材料，通过定位试验研究小麦玉米秸秆全量还田对玉米抗倒性能的影响。【结果】小麦或玉米秸秆全量还田均能提高玉米气生根条数、0—30 cm土层根条数及根系干重，同时，玉米株高和单株鲜重均有所增加。秸秆还田后，在吐丝期和灌浆中期，玉米茎秆基部3—7节间的长度、直径、干重和单位茎长干物质重有增加的趋势，尤其是基部节间的茎秆压碎强度和穿刺强度显著提高。另外，玉米的根倒伏系数显著降低，而植株抗倒指数则显著升高。相关分析表明，根倒伏系数与根倒率显著正相关，而与单株鲜重、根系干重和基3节压碎强度显著负相关。玉米总倒折率与节间长度极显著正相关，而与节间干重、充实度、压碎强度和穿刺强度显著负相关。【结论】小麦玉米秸秆连续全量还田可以显著降低夏玉米的根倒率和茎折率，提高籽粒产量。

Effects of Wheat and Maize Straw Returned to the Field on Lodging Resistance of Maize in Lime Concretion Black Soil Region

【Objective】 The objective of the experiment is to study the effects of straw returned to the field on lodging resistance of maize in lime concretion black soil region. 【Method】 Maize cultivar Zhengdan 958 was grown in this plot experiment to investigate the effects of straw returned to the field on lodging resistance of maize. 【Result】 The results showed that wheat or maize straw returned to the field could increase aerial root number, root number in 0-30 cm soil layer and root weight, so as the plant height and fresh weight of maize. After straw returning, the length, diameter, dry weight and ratio of dry weight to length of internodes from bottom 3rd to 7th were increased especially the stalk crash strength and stalk rind penetrain strength of bottom internodes were significantly increased at silking and filling stage. In addition, the root lodging coefficients were a significantly decreased while the lodging resistance indexes were significantly increased. The correlation coefficient showed that there was significant positive correlation between root lodging coefficient and root lodging percentage while there was a negative significant correlation among root lodging coefficient, fresh weight, root weight and stalk crash strength of bottom 3rd internode. The relation between total lodging percentage and internode length was a very significant post ive correlation while that among total lodging percentage and the dry weight, plumpness, crash strength and rind penetrain strength of internodes were a significant negative correlation. 【Conclusion】Therefore, under the condition of wheat and maize straw returned to the field, the root lodging percentage and stalk breaking percentage of maize would be decreased while the grain yield would be increased.