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Viruses that are primarily or exclusively found in insects are currently placed in 12 families and one unclassified group. The DNA-containing viruses are baculoviruses (BVs), NPVs, granuloviruses (GVs), ascoviruses, iridoviruses, parvoviruses, polydnaviruses, and poxviruses.

Insect virus

Commonly used defoamers can be divided into silicone (resin), surfactants, paraffins and mineral oils according to their components.

1. Silicon (resin)

Silicone resin defoamer, also known as emulsion type defoamer, is used by emulsifying and dispersing silicone resin in water with an emulsifier (surfactant) and then adding it to wastewater. Silica fine powder is another silicon defoamer with better defoaming effect.

2. Surfactants

This type of defoamer is actually an emulsifier, which uses the dispersing effect of a surfactant to keep the foam-forming substance dispersed in a stable emulsified state in water, thereby avoiding the formation of foam.

3. Paraffins

Paraffinic defoamer is a defoamer made by emulsifying and dispersing paraffinic wax or its derivatives with an emulsifier. Its use is similar to that of surfactant-based emulsified defoamers.

4. Mineral oil

Mineral oil is the main defoaming ingredient. In order to improve the effect, sometimes metal soap, silicone oil, silicon dioxide and other substances are mixed together. In addition, various surfactants can sometimes be added to make the mineral oil easily spread to the surface of the foaming liquid, or to evenly disperse the metal soap in the mineral oil.

Fungicide products containing Bacillus subtilis can be used to control tomato gray mold, rice blast, wheat powdery mildew, citrus green mold, tobacco black shank and cabbage soft rot and other diseases.

Studies have found that Bacillus subtilis can secrete antibiotics, cell wall degrading enzymes, chitinase and other substances to inhibit the germination of pathogenic fungal spores and the growth of hyphae. Substances digest mycelia, dissolve spore cell walls, etc.

A number of Bacillus strain resources have been found so far, and these strains can effectively control rapeseed clubroot, potato black shank, wheat head blight, cucumber corynesporium leaf spot, cucumber anthracnose, sweet potato stem rot, and tomato rot. Leaf spot and tomato powdery mildew etc.

MbNPV (MAMESTRA BRASSICAE NPV) has a relatively broad spectrum and can infect more than 30 kinds of Lepidoptera insects. MbNPV can be used to develop broad-spectrum viral insecticides.

MbNPV can control pests such as Spodoptera frugiperda, diamondback moth, cotton bollworm, corn borer, rice leaf roller, tea geometrid, tobacco budworm and cutworm. When 2 billion PIB/mL MbNPV SC 750mL/hm2 was applied, the control effect on rice leaf roller 7 days after application reached 90.08%.

And it will not affect the populations of natural enemies such as spiders, staphylinidae latreille, and Cyrtorhinus lividipennis.

Fungal insecticides are the most widely used type of microbial insecticides except bacterial insecticides. At present, the active ingredients of fungal insecticides mainly include Beauveria bassiana, Metarhizium anisopliae and Paecilomyces lilacinus (Thom.) Samson, etc. These fungi are highly infective, The insecticidal effect can be achieved through mycelium invasion of insects, enzymatic hydrolysis, and inhibition of insect immunity.

The highly virulent strain of Metarhizium anisopliae is pathogenic to a variety of pests and can efficiently infect Lepidoptera, Coleoptera, Orthoptera, Diptera, Hymenoptera, Hemiptera and Thysanoptera30 A variety of important agricultural pests, but does not infect natural enemies such as dragonflies, parasitic wasps, praying mantises and ladybugs.

Beauveria bassiana, as another widely used active ingredient of fungal insecticides, can infect a variety of insects. After its spores attach to insects, they can kill pests through spore growth, mechanical invasion, and enzymatic hydrolysis. .

In recent years, the number of Beauveria bassiana insecticides has gradually increased, and the scope of control has become wider and wider. As of December 31, 2022, a total of 29 pesticides with Beauveria bassiana as active ingredients have been approved for registration. It can control crop pests such as diamondback moth, pine caterpillar, corn borer, American white moth Hyphantria cunea, grub Trypoxylus dichotomus, fall armyworm, stem borer and aphids. Studies have found that Beauveria bassiana has good effects on controlling thrips, gray tea looper Ectropis grisescens, locusts, rice leaf rollers and brown planthoppers and other pests.

Microsporidia are obligate parasitic unicellular protozoa that can develop and divide in tissue cells, reproduce indefinitely, and are infectious.

Microsporidia proliferate in large numbers in the host cells, gradually replace the host cytoplasm, severely damage the endoplasmic reticulum, mitochondria, and nucleus of the host cells, severely damage the metabolic function of the cells, and eventually lead to cell fragmentation and death.

The “plant-Trichoderma-pathogen” triangle is a complex network of numerous processes. Trichoderma, a non-toxic opportunistic plant symbiont, is a low-cost, highly effective, eco-friendly biocontrol agent.

They can establish In various pathological systems, with minimal impact on soil balance and without damage to organisms that contribute to the control of pathogens, this symbiotic relationship results in plants acquiring resistance to pathogens, improving developmental processes and yields, and facilitating nutrient uptake and fertilizers Efficiency of utilization.

Antagonism, competition, and parasitism are the main features that prevent development in response to the presence of other competing pathogens.

Also include biosynthesis and stimulation of targeted metabolites such as plant growth regulators, enzymes, siderophores, antibiotics, etc. .

Trichodermas from Lin Chemical International

Trichoderma harzianum

Trichoderma Viride

Bactericides are one of the main types of microbial bactericides, and they are also the most widely used microbial bactericides.

At present, the active ingredients in the bacterial fungicides registered in my country mainly include Pseudomonas fluorescens, Bacillus subtilis, Bacillus amyloliquefaciens and Bacillus cereus, etc.

Most of them are Bacillus subtilis Ingredients of fungicides. Fungicides containing Bacillus subtilis have been approved for registration, and these products can be used to control diseases such as tomato gray mold, rice blast, wheat powdery mildew, citrus green mold, tobacco black shank and cabbage soft rot. Studies have found that Bacillus subtilis can secrete antibiotics, cell wall degrading enzymes, chitinase and other substances to inhibit the germination of pathogenic fungal spores and the growth of hyphae. Substances digest mycelia, dissolve spore cell walls, etc.

A number of Bacillus strain resources have been found so far, and these strains can effectively control rapeseed clubroot, potato black shank, wheat head blight, cucumber corynesporium leaf spot, cucumber anthracnose, sweet potato stem rot, and tomato rot. Leaf spot and tomato powdery mildew etc.

Viral insecticides mainly cause pathogenic or lethal effects on insects through the life activities of viruses. The active ingredients of viral insecticides with a long history of research in my country include nuclear polyhedrosis virus, NPV, and granular Virus Granulosis virus and Reoviridae cytoplasmic polyhedrosis virus Cytoplasmic polyhedrosis virus, CPV.

Main nuclear polyhedrosis virus are including Helicoverpa armigera NPV and Spodoptera exigua NPV, Spodoptera litura NPV, Autographa californica NPV, Mamestra brassicae NPV, etc. are the most diverse types of viral insecticides, Control various agricultural pests such as beet armyworm, cotton bollworm, tobacco budworm Heliothis assault Guenee, rice leaf roller, corn borer and cutworm Agrotis sp.; and insecticides with granular virus and cytoplasmic polyhedrosis virus as active ingredients There are 6 and 3 species respectively, and the main control targets are diamondback moth, Pieris rapae, rice leaf roller and pine caterpillar.

Bacterial Insecticides mainly refer to microbial pesticides that use certain insecticidal bacteria to achieve disease-causing or lethal effects on various pests.

The main active ingredients are Bacillus thuringiensis (Bt), Empedobacter brevis and Bacillus sphaericus, etc. , These bacteria can secrete toxin proteins, affecting the growth and development of pests.