农药对农业的生产起了很重要的作用,同时也给作物带来或多或少的不利影响,如果这种不利的影响加重,引起作物出现不正常的反应,造成减产和品质下降,即是药害。药害有轻有重、有急有缓,就症状归纳起来有以下几种: 一、斑点这种药害主要表现在叶上,有黄斑、褐斑、枯斑等。如丁草胺在水稻本田初期施用造成褐斑,代森锰锌浓度高会引起稻叶边缘枯斑。有时斑点也表现在茎枝和果实上,如梨小果吋施用代森锰锌易出现果面斑点。 Pesticides play a very important role in agricultural production, but they also have more or less adverse effects on the crops. If such unfavorable effects are aggravated, they will lead to abnormal crop reactions, which will lead to a decrease in yield and a decrease in quality Injury. There are light and heavy trauma, there is urgency and ease, the symptoms summed up the following: First, the spot This kind of phytotoxicity mainly in the leaves, there are macular, brown spots, dead spots and so on. Such as butachlor applied in the early rice Honda cause brown spots, high concentrations of mancozeb cause rice leaf edge blight. Sometimes spots are also manifested in the stems and fruits, such as pear small size application of mancozeb prone to fruit surface spots.