What are the main types of nematicides?

There are five main types of nematicides, namely antibiotics, carbamates, organophosphates, halogenated hydrocarbons, and methyl thioisothiocyanate.

Nematicides are used by many growers, and the main role of nematicides is to eliminate pathogens on plants, in fact, most of the nematicides are used for soil treatment in the early stage, that is to say, the soil and nematicides are mixed, so that many diseases and insects in the soil can be eliminated, and they can also be used for seed and seedling treatment, which can well ensure that seeds and seedlings are free of diseases and pests, so that they will not be affected by pests and diseases in their growth cycle.

In fact, when nematicides were first invented, they belonged to fumigant insecticides, and then gradually appeared carbofuran, aldicarb, etc., and these belong to non-fumigant insecticides. No matter how it is changed, the principle of eliminating nematodes is almost the same. Now nematicides are gradually changing for the better, from the previous fumigation type to the current non-fumigation type, the previous toxicity is relatively high and now the nematicides are low-toxicity, and there is a protective effect on plants.

Nematicide not only has the function of killing nematicides, but also has a very strong bactericidal and insecticidal effect, and even some even have herbicidal properties, nematicides can greatly reduce the number of nematicides in a short period of time, and can also eliminate many pests in the soil, so it has a significant effect after use, although nematicides are now widely used, but it still has some shortcomings, such as its dosage is very large, and the cost of prevention and control is relatively high, Therefore, when using nematicides, comprehensive control measures must be adopted.

At present, there are two types of nematicides on the market, one is an obligate nematicide used specifically for nematodes, and the other is a nematicide, that is, a facultative nematicide, which can not only eliminate nematodes, but also kill many pests and bacteria in the soil.

According to the control object, nematicides can be divided into two categories, one is obligate nematicides, that is, pesticides that specialize in the prevention and control of nematodes; The second is facultative nematicides, which have a variety of uses, such as chloropicrin, methyl bromide, etc., which have an effect on underground pests, pathogenic bacteria, and nematodes.

There are halogenated hydrocarbons, this type of agent has been banned, there are a lot of toxins, isothiocyanates, this can be used, and the toxicity is relatively strong, organophosphorus, can be used in the soil, can play a role in contact.

The main types are, halogenated hydrocarbons, isothiocyanates, organophosphorus, carbamates, granules, these are the main types.

There are mainly two types, one of which is an obligate nematicide, and the other is a compatible nematicide, and then the composition of these pesticides is completely different, and the chemical structure is completely different, and the effect is almost the same.

What do you know about the main types of nematicides?

Nematicides are all too familiar to vegetable farmers and are often used when growing vegetables. It has a good inhibitory killing effect. What do you know about the main types of nematicides?

The first point is organic sulfur, such as carbon disulfide and carbon sulfide. Isothiocyanates: Some soil fungicides can decompose methyl isothiocyanate in the soil. When used in powder, liquid, or granular form, it can inactivate certain sulfhydrylases in nematodes, leading to poisoning and death.

Most are soil fumigants, which directly poison nematodes by spreading them in the soil. Due to their high toxicity to humans, the development of such nematicides is limited.

The second point is methyl thioisothiocyanate. These nematicides can release methyl thioisothiocyanate, which poisons nematodes. This nematicide is developing rapidly.

The mechanism of action is that cholinesterase is inhibited and poisoned to death. Nematodes are usually susceptible to these agents. Many varieties have a systemic effect, while others show contact killing effect.

The nematicidal spectrum has a wide range and has a low amount of residue in the soil. It is an ideal nematicide at present.

The third point is complex biological fungi. Biological hyphae penetrate the epidermis of eggs and larvae, causing the epidermis and somatic cells of eggs and larvae to rapidly shrink and dehydrate, then die and digest. It was also decided that the use of this product would be extended to the stage of crop growth, but it would take a time cycle to kill nematodes, which would not be as good as chemicals.

It not only has a good inhibition and killing effect on nematodes, but also has a good control effect on root-knot nematode disease.

The fourth point is halogenated hydrocarbons. It is a low-boiling gas or liquid fumigant used to anesthetize nematodes in soil to kill. After use, it should pass through a safe interval and then plant the crop.

The large amount of this agent makes it difficult to use a dedicated soil syringe. Some varieties, such as dibromochlorool, have been banned due to toxicity and have been phased out. organophosphates and carbamates, it can also ** underground pests.

What are the insecticides for the prevention and control of vegetable nematode disease? Abamectin, insecticide, abadin, alimite, manzocin, 7051 insecticide and so on, these are particularly good insecticides. The insecticidal principle of these drugs is mainly manifested in high contact killing, stomach toxicity, and systemic efficacy.

Destroy all normal transmission of insects. Kill pests. For peach trees, wheat, peanut kernels, cotton wool, vegetables and fruits and other crops of budworms, whiteflies, planthoppers, whiteflies, budworms, etc.

At the same time, the toxicity to small animals is low. It has a very obvious protection effect on beneficial insects such as predatory mites. And it is not mobile in the soil environment, and it is degradable, and it is not very suitable for crop crops after surface water.

The insecticidal power in the field is mainly manifested in 1-3 days, with a lasting effect of 4-10 days and a residual effect of more than 20 days. In use. Spray with L0 acetamiprid wettable powder 4000-6000 times.

or 5 acetamiprid wettable powder 2000-3000 times liquid spray. Vegetable and fruit insecticide is a common chemical pest control chemical Chinese medicine preparation for farmers when planting vegetables, which can reasonably control the production of pests and improve efficiency.

Stem nematodes are mainly harmful to the underground stems of vegetables, such as tubers, bulbs and roots, and can also be harmful to the ground fruits, such as peanut pods. It causes necrosis and decay of plant tissues, dwarfing, discoloration and deformity of plants. Important diseases include potato stem nematode disease, peanut stem nematode disease, and onion and garlic vegetable stem nematode disease.

Nematicides are also different from general fungicides, which are more toxic and are generally used for soil treatment or seed treatment, and are easy to cause environmental pollution if used improperly. There are two types of nematicides: exertive and non-exercisive. The former plays a role in fumigation, and the latter plays a role in contact killing.

The effective nematicides in production are some biocidal soil fumigants, mainly methyl bromide, chloropicr, sulfuryl fluoride, etc., which are mainly used in the soil fallow period; The nematicides used in the crop growth period have a general control effect of only 50 60, and many are highly toxic insecticides. Three kinds of nematicide pesticides commonly used in vegetables: Wei Baimu and Mianlong are biocidal pesticides, which are not only used for the prevention and control of nematode diseases, but also can control underground pests and soil-borne diseases and weeds; Thiazophosphine is a specialized nematicide.

To control vegetable root-knot nematodes, you can use avithiazolephos!

There are Vebamu and Mianlong, as well as thiazolphosphine, these three are the more common insecticides for nematodes, which can also be very good for nematodes and make vegetables healthier.

Abamectin, insecticide, abadin, alimite, manzocin, 7051 insecticide and so on, these are particularly good insecticides.

1. Dichlorvos: It is a high-efficiency and low-toxicity organophosphorus preparation, which has strong contact killing, fumigation and stomach toxicity effects, and has a wide range of insecticidal effects, fast speed, short efficacy period and small residual toxicity;

2. Dimethoate: It is a high-efficiency and low-toxicity broad-spectrum organophosphorus pesticide with slag, which has the effects of contact killing, systemic absorption and stomach toxicity;

3. Dimethoate: It has the effects of contact killing, systemic absorption and gastric toxicity, and can prevent and control many stinging and chewing mouthparts pests, and has great acute gastric toxicity to humans and animals;

4. Malathion: there are contact killing, stomach poisoning and fumigation for royal use, high efficacy, wide range of insecticide, residual effect period is generally about a week, less toxic to humans and animals, safer;

5. Parathion: also known as 1605, it is a widely effective highly toxic insecticide. It has strong contact killing, gastric toxicity and fumigation effects, and has a good eggicidal effect, but no systemic infusion effect.