Scientific selection of pesticides for pollution-free vegetable pest and disease control
At present, in producing pollution-free vegetables, it is still difficult to completely avoid the use of pesticides, plant hormones and chemical fertilizers, but their use must be strictly controlled. Highly efficient, low-toxicity and low-residue organic chemical pesticides may be used to a limited extent, while pesticides that are highly toxic, highly residual and have "three-causing (carcinogenic, teratogenic, mutagenic)" effects are strictly prohibited. The use of highly efficient, low-toxicity and low-residue chemical pesticides is advocated, and they should be used in combination with other control measures; chemical pesticides should be scientifically screened and their combinations optimized. The standards for safe use of pesticides must be strictly implemented, and in particular the pre-harvest safety interval for pesticide use on vegetables must be strictly observed. The principle of applying pest and disease control only when the threshold is reached must be adhered to; do not use pesticides when the control threshold is not reached, and overcome the bad habit of blind and indiscriminate pesticide use. Pest and disease control should start from the seedling-raising field, controlling and reducing the number of pesticide applications, to ensure that toxic residues in vegetables do not exceed the standards set by the state.
Prohibition of highly toxic and highly residual pesticides
In vegetable pest and disease control, there are many types of chemical pesticides that can be used, but they must be strictly controlled, and highly toxic and highly residual pesticides are prohibited. For example, highly toxic pesticides such as 3911, 1605, 1059, BHC, DDT, carbofuran, isofenphos-methyl, methamidophos, zinc phosphide, omethoate, monocrotophos, chlordimeform, dicofol, fluoroacetamide and organomercury preparations are all strictly prohibited.
Fungicides permitted for controlling vegetable fungal diseases
The fungicides permitted for controlling vegetable fungal diseases in pollution-free vegetable production include: 75% chlorothalonil 600x solution, 70% mancozeb 500x solution, 80% fosetyl-aluminum 500x solution, 75% metalaxyl 800x solution, 72% kewen 600x solution, 58% metalaxyl-mancozeb 600x solution, 50% procymidone 1500x solution, 50% iprodione 1000x solution, 50% carbendazim 500x solution, 50% vinclozolin 500x solution, 50% duomeiling 1000x solution, 50% thiophanate-methyl 500x solution, 64% sandofan 500x solution, 34% lülutong 500x solution, 80% anthracnose-fumei 500x solution, etc. Among these, carbendazim (carbendazim-diethofencarb) and sandofan are compound formulations. When spraying, generally 50-70 kg of solution is used per mu, with less used at the seedling stage or for leafy vegetables.
Dust formulations permitted for use
The dust formulations permitted for use include: 20% (or 40%) chlorothalonil smoke agent 300 g/mu, 50% chlorothalonil dust 1 kg/mu, 10% (or 20%) procymidone smoke agent 300 g/mu, 10% miekefen 1 kg/mu, as well as iprodione smoke agent and ditor dust, etc. In addition, for controlling aphids, aphid-killing smoke agent 350 g/mu can also be used. Dust formulations are mostly applied inside protected cultivation facilities; they not only have high efficacy but also do not increase the humidity inside the greenhouse, thereby reducing the occurrence of diseases.
Bactericides permitted for controlling vegetable bacterial diseases
The bactericides permitted for controlling vegetable bacterial diseases include: 5-10 million units agricultural streptomycin 4000x solution, 50% copper ammonium complex 500x solution, 30% DT bactericide, 50% fenghuan 500x solution, 27% copper high suspension concentrate, 34% lürutong 500x solution, 77% koshide 500x solution, etc.
Agents permitted for controlling vegetable viral diseases
The agents permitted for controlling vegetable viral diseases include: junduqing 300x solution plus 50% pirimicarb 2000x solution (also controls aphids), 5% junduqing 300x solution, 1.5% zhibingling 500x solution, 83-1 resistance enhancer 200x solution, zinc sulfate 800x solution, lüfenwei No. 1 1000x solution, 20% virus A 500x solution, antivirus agent No. 1 400x solution, antitoxin 500x solution, trisodium phosphate 500x solution, etc. At the same time, milk and glucose can be sprayed on the leaves, and foliar fertilizers containing phosphorus, potassium and zinc can also be sprayed. In addition, when inoculating with virus vaccine, for example, dipping roots with 100x weak virus vaccine 14N for half an hour at the seedling transplanting stage can prevent tomato viral disease.
Pesticides permitted for controlling vegetable pests
Agents for controlling leafminers: 25% acetamiprid water-dispersible granules 3000-5000x solution, 25% aikashi 1000x solution, 20% fenvalerate-malathion emulsifiable concentrate 2000x solution, 21% mieshabi emulsifiable concentrate 3000x solution, etc. In addition, abamectin, lücaibao, cyromazine, anlübao, chongman-guang and saikai can also be used (generally 70 kg of solution per mu), and yellow sticky boards can also be used to trap and kill adults.
Agents for controlling whiteflies: 25% acetamiprid water-dispersible granules 2500-5000x solution, 25% buprofezin 2000x solution, 10% wanling 1000x solution (60 kg of solution per mu); aphid-killing smoke agent 350 g/mu can also be used.
Agents for controlling tea yellow mites: 73% propargite 1000x solution, 25% manmeng 1500x solution, 10% mansijing 3000x solution, 1.8% abamectin 8000-10000x solution, 15% pyridaben 2500-3000x solution, etc.
Agents for controlling aphids: 5% acetamiprid water-dispersible granules 5000-10000x solution, 25% aikashi 1000x solution, 10% wanling 1000x solution, 50% pirimicarb 2000x solution, 10% imidacloprid 4000-6000x solution, 10% acetamiprid 300x solution; aphid-killing smoke agent 250 g/mu can also be used for fumigation. In addition, silver-gray materials can be used to repel aphids or yellow sticky boards to trap and kill them.
Agents for controlling cotton bollworm, cabbage caterpillar, etc.: 25% cyhalothrin emulsifiable concentrate 5000x solution, tianwangxing (bifenthrin) 10% emulsifiable concentrate 1000x solution, mieshabi 3000x solution (generally 50 kg of solution per mu). In addition, adults can be trapped and killed.