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- 2015
水稻秸秆还田结合炔草酯对禾本科杂草和小麦生长发育的影响
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Abstract:
为改进水稻秸秆还田条件下小麦田杂草治理技术,通过田间小区试验研究了不同还田量单独或结合炔草酯施用对后茬小麦田禾本科杂草的控制效果和小麦生长发育及产量的影响。结果表明,随着水稻秸秆单独还田量从1 125 kg/hm2增至4 500 kg/hm2,小麦田杂草发生密度显著下降,4 500 kg/hm2秸秆还田量下小麦分蘖期前杂草发生密度下降60%左右;结合炔草酯施用时,杂草发生密度随秸秆还田量的增加而下降,但不同还田量之间显著差异,且炔草酯除草活性未受到影响。秸秆还田或炔草酯单独或结合施用均对小麦生长发育明显的胁迫影响,4 500 kg/hm2秸秆单独还田量下,小麦苗期功能叶SPAD值较对照增加7.0%,净光合速率和蒸腾速率分别增加14.9%和12.2%;抽穗期净光合速率、气孔导度、蒸腾速率分别增加28.3%、85.2%和100.0%;千粒重、有效穗数和产量分别增加3.9%、6.7%和16.1%。4 500 kg/hm2秸秆单独还田量对杂草控制效果、小麦生长及产量的影响均与炔草酯推荐剂量单独施用显著差异,表明该秸秆还田量具有良好的农田生态效应。
This study investigated effects of rice-straw residues and the herbicide clodinafop-propargyl on wheat and Gramineae weeds in wheat fields. The objective was to improve Gramineae weed management in wheat fields by applying rice-straw residues. The increase in rice-straw residue from 1 125 kg/hm2 to 4 500 kg/hm2 significantly reduced the weed density. When the rice-straw residues were at 4 500 kg/hm2, the weed density was reduced by about 60% before the tillering stage of wheat. With the rice-straw residues and clodinafop-propargyl being applied together, the weed density in wheat fields further decreased with the increase of rice-straw residues, but the decreases were not significant among treatments of rice-straw residues with clodinafop-propargyl application. Also, negative effects of the rice-straw residues on the efficacy of clodinafop-propargyl were not observed. The applications of rice-straw residues or clodinafop-propargyl and their combination did not show a negative effect on the growth of wheat crops. The rice-straw residue at 4 500 kg/hm2 in wheat increased the SPAD of functional leaves by 7.0%, net photosynthetic rate by 14.9% and transpiration rate by 12.2% at seedling stage of wheat, and net photosynthetic rate by 28.3%, stomatal conductance by 85.2% and transpiration rate by 100.0% at heading stage of wheat when compared to the control (without use of rice-straw and clodinafop-propargyl). With the application of the 4 500 kg/hm2 rice-straw to following wheat, 1 000-grain weight, effective number of panicles and yield of wheat were increased by 3.9%, 6.7% and 16.1%, respectively, compared to the control. Compared to only application of clodinafop-propargyl at recommended dose, the rice-straw residues at 4 500 kg/hm2 had no significant difference in the control of Gramineae weeds, and the effect on growth and yield of wheat. Therefore, the application of rice-straw residues at 4 500 kg/hm2 to wheat is recommended.