江苏溧阳水稻田减量用药研究初探

为尽可能减少稻田农药的使用量，更好地保障稻米品质及保护农田生态环境，通过优化药剂组合和施药次序，综合田间防效、消解动态、最终残留及水稻产量等因素，研究评估了江苏省溧阳市水稻田农药减量施用的可行性。分别设置常规施药组合和减量施药组合2套方案，以水稻主要病虫害稻飞虱、稻纵卷叶螟及纹枯病为例，比较了2种施药方案下对病虫害的防效，分析了相关药剂在水稻中的残留消解动态以及在稻米和谷壳中的最终残留，并对水稻产量进行了考察。结果表明:减量施药方案对水稻上3种典型病虫害的防效均优于或与常规施药方案相当；此外，不同施药次序对水稻病虫害的防治效果差异较大；2种施药方案下，供试药剂在稻米中的最终残留量均未超过其残留限量 (MRL) 标准；与常规施药方案相比，减量施药方案下水稻每公顷产量增加了621 kg，但二者差异不显著。减量方案施用农药总制剂量为4 410 g/hm2 (有效成分1 353 g/hm2), 而常规方案为6 885 g/hm2 (有效成分1 553 g/hm2)。研究表明，在试验期间，该减量施药方案能有效防控水稻病虫害，保证水稻产量，同时还能减少环境中农药及助剂的投入，降低对环境的危害。

A pilot study of pesticide reduction strategy in paddy fields at Liyang, Jiangsu Province

In order to reduce the use of pesticide in paddy field, improve rice quality and protect agricultural eco-environments, the feasibility of pesticide reduction strategy in paddy fields was tested at Liyang, Jiangsu Province. The analyzing control effects, pesticide dissipation, final residues and the yield were investigated. Conventional and reduction strategies were both evaluated. Three typical rice diseases and insect pests were chosen as examples. The prevention and control effects of these diseases and pests in paddy field, the residues of the pesticide in rice, and the yield were determined to evaluate the efficacy of these strategies. The results showed that the prevention and control effects of these three main diseases and pests using reduction strategy were better than or equal to the conventional strategy. The residues of pesticide in rice were all below the maximum residue limit in the experiments using both strategies. The yield was increased by 621 kg/hm² with the reduction strategy, but the differences were not significant. The total amount of pesticide used in the reduction strategy was 4 410 g/hm² (1 353 g a.i./hm²), and which in the conventional strategy was 6 885 g/hm² (1 553 g a.i./hm²). Hence, the reduction strategy not only prevented and controlled the diseases and pests effectively and ensured the yield of rice, but also greatly reduced the input of pesticide and adjuvants in the environment, which reduced the harm to the environment.