When pesticides are used to control vegetable pests and diseases, the dosage is small, the control effect is good, and the toxicity to humans, animals and various beneficial organisms is small or non-toxic, requiring easy decomposition in the external environment, and not causing high efficiency and low toxicity to the environment and agricultural products. Low residual pesticides. Specifically: the dosage per acre must be determined from the actual situation. Through experiments, the economically effective concentration and dosage should be determined. It should not be too high or too low. Generally, the insecticidal effect is over 90%, and the disease prevention effect is more than 80%. High-efficiency pesticides; use (LD50) low-toxic pesticides with a lethal median value of more than 500 ml/kg body weight; the harvested commercial vegetables should pay attention to the safety interval of pesticides, so that the pesticide residue must be lower than the national standard.
1. Biological pesticides
Bio-sourced pesticides refer to the direct use of biologically active substances produced by biological organisms or biological metabolic processes or substances extracted from organisms as pesticides for controlling diseases, insects, grasses and other harmful organisms. Specifically, it can be divided into plant-derived pesticides, animal-derived pesticides and microbial-sourced pesticides. Such as: BT, pyrethrin, nicotine allicin, sex pheromone, Jinggangmycin, Nongkang 120, Liuyangmycin, streptomycin, polyoxymycin, avermectin, brassinolide, except Alizarin, alkaloids, etc.
Second, mineral source pesticides (inorganic pesticides)
The active ingredient is a generic term for inorganic compounds derived from minerals. There are mainly sulfur preparations, copper preparations, and phosphides. Such as copper sulfate, Bordeaux mixture, stone sulfur mixture, zinc phosphide and the like. Arsenic preparations and fluorides with high toxicity and high residual content are not included in the recommended range.
Third, organic synthetic pesticides
It is limited to organic whole pesticides with low toxicity, low residue and safe use. It is recommended to use safe pyrethroids, some medium and low toxicity organophosphorus, organic sulfur and other insecticides , fungicides and some low-toxic diphenyl ether herbicides after many years of application. Such as: cypermethrin, deltamethrin, dimethoate, dichlorvos, phoxim, carbendazim, chlorothalonil, metalaxyl, triadimefon, chlorpyrifos, methotrexate, anti-coccin, grass and spirit, thin Kill, grass, ger, dur and so on. High-residue organochlorine pesticides, secondary poisoning of fluoroacetamide, and metabolites such as ethylene thiourea with "triad" are not recommended.
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