CN115633702A - Preparation and application of wettable powder - Google Patents

Abstract

The invention provides preparation and application of wettable powder, belonging to the technical field of pesticides, wherein the wettable powder comprises 50wt% of clothianidin, 6.25wt% of deltamethrin, 6.25-30 wt% of perlite, 5wt% of dispersant, 4wt% of wetting agent, 0.5wt% of defoaming agent, 1wt% of citric acid and 2wt% of white carbon black, and the balance of kaolin is complemented; the wettable powder is applied to the prevention and treatment of mosquitoes, and the application dosage is 400mg/m ² Wherein the administration dose of each component is: clothianidin 200mg/m ² Deltamethrin 25mg/m ² 25-120 mg/m of perlite ² . The wettable powder is prepared byAfter being compounded, the active ingredients of the clothianidin, the deltamethrin and the perlite in different action modes have good effect on preventing and controlling mosquitoes, and have obvious synergy and lasting effect and the function of preventing drug resistance.

Description

Preparation and application of a wettable powder

technical field

The invention relates to the technical field of pesticides, in particular to the preparation and application of a wettable powder.

Background technique

Malaria is a life-threatening disease caused by parasites of the Plasmodium genus that are transmitted to humans through the bite of infected female Anopheles mosquitoes known as "malaria vectors." Indoor residual spraying (IRS) is a powerful malaria control intervention. This is because mosquitoes, the vector of malaria, are related to the environment in which people live. The indoor residual sprayed insecticide is diluted with water in a certain proportion and then sprayed on the wall, that is, when the mosquitoes that transmit malaria enter human residences or raise animals Before and after blood sucking in buildings, they will stay on the inner walls, eaves and ceiling surfaces to rest, so as to come into contact with the long-lasting, residual active insecticides sprayed on the surface. When they absorb the lethal dose, they will die. death, leading to a reduction in population density, thereby reducing malaria transmission.

Indoor Residual Spraying (IRS) control of malaria vectors in Africa has increased significantly in recent years due to the increasing influence and funding of programs such as the Global Fund and the President's Malaria Action Plan. This, coupled with the mass distribution of long-lasting insect nets (LLINs), has greatly reduced malaria morbidity and mortality. Insecticides recommended by WHO for indoor residual spraying (IRS) include 12 insecticides in four categories including DDT, pyrethroids, organophosphates and carbamates. Except for DDT, the other three types of insecticides recommended by WHO have a relatively short residual activity on local walls, usually only 2-6 months, so multiple rounds of spraying are required in areas where malaria spreads throughout the year. This poses a major challenge to the effective use of IRS in most of sub-Saharan Africa due to the repeated implementation of IRS spraying campaigns.

Of the four classes of insecticides recommended by WHO, pyrethroids are the most widely used due to their low cost, low mammalian toxicity and efficacy. Yet resistance to DDT and pyrethroids has developed throughout sub-Saharan Africa. Furthermore, insensitivity to acetylcholinesterase (Ace1R) has been reported in several regions of West Africa leading to the emergence and spread of organophosphate and carbamate resistance. Therefore, there is an urgent need to develop new, long-acting, IRS insecticides with no cross-resistance to current insecticides or cheap and safe substitutes. In terms of resistance management, the combination of two or more insecticides or active ingredients with different modes of action can not only combine the advantages of various active ingredients, enhance the insecticidal effect, and prolong the duration; The rate of development of resistance.

Clothianidin is a neonicotinoid insecticide. Neonicotinoid insecticides are a new class of insecticides for public health. Neonicotinoid insecticides are widely used in the protection and control of crops. Insect sucking and veterinary drug used to control fleas on cats and dogs, exhibiting very good biological efficacy against a broad spectrum of insect pests such as Hemiptera, Coleoptera, Thysanoptera, Lepidoptera and Diptera. Clothianidin acts as a agonist of the nicotinic acetylcholine receptors, exhibiting a mode of action different from that of pyrethroid, organophosphate, and carbamate insecticides. Because neonicotinoid insecticides have very low affinity for vertebrate nicotinic receptors compared to insect nicotinic receptors, they are promising for public health use. Given this novel mode of action, neonicotinoid insecticides show the potential to improve control of vector populations that have developed resistance to existing public health insecticides.

The use of insecticides with different modes of action as combination formulations for IRS has great potential in improving malaria vector control and in managing insecticide resistance in areas where not all active ingredients develop resistance because if the If an area develops resistance to only one of the combination formulations, the other non-resistant active ingredients in the combination formulation will continue to work to kill mosquitoes.

Perlite is a mineral derived from volcanic rock that acts as a mechanically acting insecticide. Preliminary laboratory experiments using WHO small bowl tests showed that the mineral, applied as dust on circular filter paper, was able to kill pyrethroid-sensitive non-blood-sucking female Anopheles gambiae (Kisumu). Mineral-derived insecticides have been reported in the literature to control agricultural pests, eg, Coleoptera, Thysanoptera, Lepidoptera and Hemiptera. On the other hand, mineral-derived pesticides have received little attention because research results were limited to laboratories. The use of perlite as a mechanically acting insecticide is novel.

Volcanic rock is an amorphous aluminum silicate that can be processed into perlite by cracking during cooling after high temperatures. Perlite is currently mainly used as a thermal insulation material or plant growth medium, identified as safe in the FDA database, and classified as a feed additive in EFSA. It has never been used for vector control before. Perlite prepared as a wettable powder diluted with water and sprayed provides a new mode of action for the insecticide, disturbing the water balance of insects. This mechanically acting insecticide disrupts the protective lipids of the cuticle of the insect, killing it by desiccation (a non-toxic, eg non-systemic mode of action). Because the insecticide is a mineral, it should last indefinitely after application. Because mineral insecticides have not previously been used for mosquito control, they should be very effective against pyrethroid-resistant mosquitoes.

Contents of the invention

The purpose of the present invention is to provide a preparation and application of wettable powder. After compounding three active ingredients clothianidin, deltamethrin and perlite with different modes of action, the wettable powder has obvious synergistic and sustained effects, and can prevent the generation of drug resistance. The wettable powder is used for controlling mosquitoes and has high inhibitory activity.

To achieve the above object, the present invention provides the following scheme:

A wettable powder comprising the following components: clothianidin 50wt%, deltamethrin 6.25wt%, perlite 6.25-30wt%, dispersant 5wt%, wetting agent 4wt%, defoamer 0.5wt%, lemon Acid 1wt% and white carbon black 2wt%, the remainder is kaolin.

As a further optimization of the present invention, it contains the following components, clothianidin 50wt%, deltamethrin 6.25wt%, perlite 30wt%, dispersant 5wt%, wetting agent 4wt%, defoamer 0.5wt%, citric acid 1wt% % and white carbon black 2wt%, the remainder is kaolin.

As a further optimization of the present invention, the dispersant includes at least one of sodium salt of alkylnaphthalenesulfonic acid polymer and sodium lignosulfonate.

As a further optimization of the present invention, the mass ratio of the sodium salt of alkylnaphthalene sulfonic acid polymer to sodium lignosulfonate in the dispersant is 1:1.

As a further optimization of the present invention, the wetting agent is sodium dodecylsulfonate.

The present invention also provides a kind of preparation method of wettable powder, comprises the following steps:

(1) Pre-mixing: Weigh the raw materials according to the requirements of the proportion, add all the weighed raw materials into the mixer, mix to form a mixed coarse material, and set aside;

(2) Airflow milling: the mixed coarse material obtained in step (1) is pulverized by an airflow mill, and through a separator, a catcher collects mixed fine material for subsequent use;

(3) Post-mixing: Add the mixed fine material obtained in step (2) into a mixer, and mix evenly to obtain a wettable powder, and then put the wettable powder into a water-soluble bag to obtain a finished product.

The present invention further provides the application of the wettable powder in preventing and controlling mosquito diseases.

As a further optimization of the present invention, the dosage of the wettable powder is 400 mg/m ² .

Clothianidin is a neonicotinoid insecticide, and its mode of action is a nicotinic acetylcholine receptor agonist. The mechanism of action is mainly to selectively control the nicotinic acetylcholinesterase receptors in the insect nervous system and block the insect central nervous system. The normal conduction of the insects will lead to paralysis and death of the pests. This type of insecticide has a unique mechanism of action and has no cross-resistance with the four types of insecticides recommended by WHO for IRS. Deltamethrin, a type II pyrethroid insecticide, acts as a regulator of sodium ion channels on insect nerve axons, adsorbs on the sodium ion channels of insects, keeps them open and prevents nerve repolarization, thereby Paralyzes the body. Perlite, a type of volcanic rock, is a mechanically acting insecticide that disrupts the protective lipids of insect cuticles, killing them by desiccation.

In the present invention, the above three active ingredients with different modes of action are prepared into a compound wettable powder preparation, and the complementary activity thus produced improves and stabilizes the performance compared with the single application of any one or two active ingredients under field conditions. , increased persistence. Demonstrated effectiveness in mosquito species resistant to pyrethroids, carbamates and organophosphates. Water-soluble packaging bag - not only improves the convenience of use but also reduces the risk of contamination of the outer packaging.

The invention discloses the following technical effects:

The present invention compounded clothianidin, deltamethrin and perlite into a wettable powder preparation, which has no cross-resistance with existing IRS preparations, can kill resistant mosquitoes, and can last for 5 months , has obvious synergistic and sustained effects, and prevents drug resistance

Detailed ways

Various exemplary embodiments of the present invention will now be described in detail. The detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features and embodiments of the present invention.

It should be understood that the terminology described in the present invention is only used to describe specific embodiments, and is not used to limit the present invention. In addition, regarding the numerical ranges in the present invention, it should be understood that each intermediate value between the upper limit and the lower limit of the range is also specifically disclosed. Each smaller range between any stated value or intervening value in a stated range and any other stated value or intervening value in a stated range is encompassed within the invention. The upper and lower limits of these smaller ranges may independently be included or excluded from the range.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although only the preferred methods and materials are described herein, any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and/or materials in connection with which the documents are described. In case of conflict with any incorporated document, the contents of this specification control.

It will be apparent to those skilled in the art that various modifications and changes can be made in the specific embodiments of the present invention described herein without departing from the scope or spirit of the present invention. Other embodiments will be apparent to the skilled person from the description of the present invention. The specification and examples in this application are exemplary only.

As used herein, "comprising", "comprising", "having", "comprising" and so on are all open terms, meaning including but not limited to.

In the embodiment, the concentration of the original drug of clothianidin is 98%, and the concentration of the original drug of deltamethrin is 98%.

Example 1:

(1) Pre-mixing: clothianidin 50wt%, deltamethrin 6.25wt%, perlite 30wt%, dispersant 5wt%, wetting agent 4wt%, defoamer 0.5wt%, citric acid 1wt% and white carbon black 2wt%, and the rest is kaolin. Weigh the raw materials according to the above ratio, add all the weighed raw materials into the mixer, mix to form a mixed coarse material, and set aside;

(2) Airflow milling: the mixed coarse material obtained in step (1) is pulverized by an airflow mill, and through a separator, a catcher collects mixed fine material for subsequent use;

(3) post-mixing: the mixed fine material obtained in step (2) is added in the mixer, mixed evenly, and packed into a water-soluble bag to obtain 50% clothianidin+6.25% deltamethrin+30% perlite wettable powder.

Comparative examples 1-6:

Repeat the steps of Example 1, according to the wettable powder preparation of single-component 50% clothianidin, 6.25% deltamethrin, 30% perlite respectively; two-component 50% clothianidin+6.25% deltamethrin , Wettable powder of 50% clothianidin + 30% perlite, 6.25% deltamethrin + 30% perlite. The material composition of Comparative Examples 1-6 is detailed in Table 1

Table 1

Element Comparative example 1 Comparative example 2 Comparative example 3 Comparative example 4 Comparative example 5 Comparative example 6 Clothianidin (98%) 51.02 0 0 51.02 51.02 0 Deltamethrin (98%) 0 6.38 0 6.38 0 6.38 Perlite 0 0 30 0 30 30 Dispersant 5 5 5 5 5 5 D 4 4 4 4 4 4 Defoamer 0.5 0.5 0.5 0.5 0.5 0.5 citric acid 1 1 1 1 1 1 Silica 2 2 2 2 2 2 Kaolin 36.48 81.12 57.5 30.1 6.48 51.12 Total 100 100 100 100 100 100

Experimental example 1

The test object was Culex gambiens. Prepare a circular shape with a diameter of 12 cm according to the mass ratio of cement and sand of 1:1, and the curing time is more than 1 month, and the surface is smooth, as the cement base material.

The wettable powders prepared in Example 1 and Comparative Examples 1-6 were diluted with water to 10mg/ml respectively, and then sprayed onto the wood board substrate using a Porter spray tower, with an application rate of 40ml/m ² , the treated substrate The target active substance is three-component clothianidin + deltamethrin + perlite, the spraying dose is 200mg/m ² +25mg/m ² +120mg/m ² , the single-component clothianidin spraying dose is 200mg/m ^2. The spraying dose of one-component deltamethrin is 25mg/m ² , the spraying dose of single-component perlite is 120mg/m ² , the spraying dose of two-component clothianidin + deltamethrin is 200mg/m ² +25mg/m ² , the spraying dose of two-component clothianidin + perlite is 200mg/m ² +120mg/m ² , the spraying dose of two-component deltamethrin + perlite is 25mg/m ² +120mg /m ² . The treated substrate is stored under the conditions of 27±2° C. and relative humidity of 80±10%. The biological effect measurement was carried out 1 week and 1-7 months after the treatment. The experimental data are shown in Table 2.

Biological test method: According to the operating procedures on the WHO guideline, 4 samples of cement substrates, each sample uses 20 mosquitoes for biological testing, a total of 80 mosquitoes are tested, the experimental device is a WHO small bowl, mosquitoes and substrates The contact time is 30 minutes. After contact, the mosquitoes will be transferred to a clean paper cup, continue to be fed with sugar water, stored at 27±2°C, and the relative humidity is 80±10%, and the lethality of the mosquitoes will be observed after 72 hours.

Table 2

fatality rate Example 1 Comparative example 1 Comparative example 2 Comparative example 3 Comparative example 4 Comparative example 5 Comparative example 6 the first week 100.00% 81.28% 42.31% 27.88% 100.00% 96.15% 50.00% first month 100.00% 65.38% 16.67% 26.65% 100.00% 92.31% 38.46% second month 100.00% 25.00% 0.00% 11.26% 100.00% 83.33% 27.88% third month 100.00% 58.65% 6.67% 7.69% 96.15% 60.71% 7.74% fourth month 95.83% 12.94% 11.03% 0.00% 36.54% 16.35% 3.85% fifth month 87.32% 3.85% 4.17% 0.00% 17.80% 8.33% 0.00% sixth month 76.56% 0.00% 0.00% 0.00% 8.01% 0.00% 0.00% seventh month 54.21% 0.00% 0.00% 0.00% 3.57% 0.00% 0.00%

Judging from the 72h lethality data of the cement substrate for 7 months, the biological effect of the wettable powder in Example 1 is significantly higher than that of the single-component and two-component wettable powders prepared in Comparative Examples 1-6, and the duration of effect can reach 5 months.

The above-mentioned embodiments are only to describe the preferred mode of the present invention, and are not intended to limit the scope of the present invention. Variations and improvements should fall within the scope of protection defined by the claims of the present invention.

Claims (8)

1. A wettable powder, characterized in that comprising the following components, clothianidin 50wt%, deltamethrin 6.25wt%, perlite 6.25 ~ 30wt%, dispersant 5wt%, wetting agent 4wt%, defoamer 0.5wt%, citric acid 1wt%, and white carbon black 2wt%, and the rest is kaolin. 2. A wettable powder according to claim 1, characterized in that it comprises the following components, clothianidin 50wt%, deltamethrin 6.25wt%, perlite 30wt%, dispersant 5wt%, wetting agent 4wt %, defoamer 0.5wt%, citric acid 1wt% and white carbon black 2wt%, the rest is kaolin. 3. A kind of wettable powder according to claim 1, characterized in that, the dispersant comprises at least one of sodium salt of alkylnaphthalene sulfonic acid polymer and sodium lignosulfonate. 4. a kind of wettable powder according to claim 3, it is characterized in that the sodium salt of alkyl naphthalene sulfonic acid polymer and sodium lignin sulfonate mass ratio are 1:1 in the dispersant. 5. a kind of wettable powder according to claim 1, is characterized in that, described wetting agent is sodium lauryl sulfonate. 6. A preparation method of the wettable powder according to any one of claims 1 to 5, comprising the following steps: (1) Pre-mixing: Weigh the raw materials according to the requirements of the proportion, add all the weighed raw materials into the mixer, mix to form a mixed coarse material, and set aside; (2) Airflow milling: the mixed coarse material obtained in step (1) is pulverized by an airflow mill, and through a separator, a catcher collects mixed fine material for subsequent use; (3) Post-mixing: Add the mixed fine material obtained in step (2) into the mixer, and continue to stir and mix evenly to obtain a wettable powder. 7. An application of the wettable powder according to any one of claims 1 to 5 in controlling mosquitoes. 8. The application of the wettable powder in controlling mosquitoes according to claim 7, characterized in that the dosage of the wettable powder is 400 mg/m ² .