1.要严格控制使用浓度和用量。每种作物对农药都有一定的承受力,超过一定浓度后极易产生药害。若发现标准浓度和剂量达不到预期效果时,不要盲目加大剂量,应更换用药品种。用量要适宜,不能过大或过小,用量过大既增加成本又污染环境;用量过小则达不到应有的防效。如近几年,伏蚜和棉铃虫危害严重, 1. To strictly control the use of concentration and dosage. Each crop has a certain tolerance to pesticides, more than a certain concentration prone to injury. If you find that the standard concentration and dose do not reach the expected results, do not blindly increase the dose, the drug should be replaced. Dosage should be appropriate, not too large or too small, excessive use of both increased costs and pollute the environment; dosage is too small will not reach the desired effect. In recent years, the aphids and bollworms endanger the seriousness,