JP2011168565A - Aqueous bait agent for mosquito and mosquito extermination method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an aqueous bait agent for mosquito free from feed aversion trouble of mosquito and having excellent quick-acting properties, and a mosquito extermination method using the aqueous bait agent for mosquito. <P>SOLUTION: The aqueous bait agent for mosquito includes at least one compound selected from 5-methoxy-3-(o-methoxyphenyl)-1,3,4-oxadiazol-2(3H)-one and 2-isopropoxyphenyl methylcarbamate as an active component. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an aqueous bait agent for mosquitoes and a method for controlling mosquitoes.

Conventionally, techniques for volatilizing liquids containing insecticidal components and repellent components, such as electric mosquito traps and incense sticks, are mainly used to control mosquitoes. As an insecticidal component of such a liquid agent, a pyrethroid-based insecticidal component that has a high mosquito knockdown effect and is easy to be thermally evaporated is used. However, when volatilizing an insecticidal component or the like, there is a problem that a human inhales the volatilized insecticidal component, and a safer extermination technique is desired.
As one of highly safe pest control techniques, there is a bait agent (poisonous bait) that uses the food poisoning action of an active ingredient. Bait agents are conventionally used for cockroaches, ants, flies, bees and the like, and the properties include solid to semi-solid and aqueous. For example, Patent Document 1 discloses a fly bait containing (5-benzyl-3-furyl) methyl-d-cis / trans-chrysantemate as an active ingredient. Patent Literature 2 discloses a neonicotinoid compound and a phenylpyrazole compound as active ingredients as poisonous baits for controlling insects such as cockroaches. Patent Document 3 discloses a bee venom containing an insecticidal component and a sugar and / or animal protein.
However, it is difficult to use these bait agents as they are for mosquito control. For example, in order for mosquitoes to feed the bait preparation, it is necessary that the bait preparation is an aqueous liquid, and accordingly, the active ingredient to be blended is also water-soluble, and mosquitoes consume the aqueous liquid. It is necessary to satisfy conditions such as not avoiding food (not showing food repellency), but none satisfying these conditions is known. In particular, many of the conventional insecticidal components cannot be used as an active ingredient of a bait because they exhibit feeding repellency.

JP-A-62-026207 JP 2007-70275 A JP 2003-238317 A

In response to the above problems, the present applicant has proposed that an aqueous solution in which boric acid and / or a salt thereof (hereinafter referred to as boric acid) is dissolved is used as a bait agent for mosquitoes (International Application No. : PCT / JP2009 / 055342).
The aqueous solution of boric acids is useful as an aqueous bait for mosquitoes because it does not exhibit feeding repellency. However, since the aqueous liquid has a slow insecticidal effect on mosquitoes, it is difficult to quickly reduce blood sucking damage.
The present invention has been made in view of the above circumstances, and the mosquito shows an oral insecticidal effect without showing feeding repellency, and has an excellent quick action and the mosquito aqueous bait. An object of the present invention is to provide a method for controlling mosquitoes using an agent.

In order to solve the above-mentioned problems, the present inventors conducted a search for compounds that are water-soluble, that mosquitoes do not exhibit feeding repellency and that have an oral insecticidal effect, and that are also excellent in rapid action. These two types of compounds were found to satisfy the above requirements, and the present invention was completed.
The present invention for solving the above problems has the following aspects.
[1] As an active ingredient at least one selected from 5-methoxy-3- (o-methoxyphenyl) -1,3,4-oxadiazol-2 (3H) -one and 2-isopropoxyphenyl methyl carbamate Contains an aqueous bait for mosquitoes.
[2] A method for controlling mosquitoes, comprising using the aqueous bait for mosquitoes according to [1].

  ADVANTAGE OF THE INVENTION According to this invention, the mosquito does not show feeding repellency and can provide the mosquito extermination method using the aqueous bait agent for mosquitoes which was excellent also in the rapid effect, and this aqueous mosquito agent for mosquitoes.

The aqueous bait for mosquitoes of the present invention is 5-methoxy-3- (o-methoxyphenyl) -1,3,4-oxadiazol-2 (3H) -one (hereinafter referred to as Compound A) as an active ingredient. And at least one selected from 2-isopropoxyphenyl methyl carbamate (hereinafter referred to as Compound B). Here, “active ingredient” means an ingredient having an oral insecticidal effect against mosquitoes.
Compounds A and B are each represented by the following structural formula.

Compound A is known by the common name of methoxadiazone and has been used extensively against cockroaches, particularly pyrethroid resistant cockroaches. In that case, a smoke agent is mainly used as a dosage form, and a part thereof is also used as an aerosol agent. However, no example of using Compound A as an aqueous bait for mosquitoes has been known so far.
Compound B is known by the general name of propoxur and is conventionally used against cockroaches, flies, ants and the like. In this case, there are aerosols, granules, and smoking agents as dosage forms, but no examples of using Compound B as an aqueous bait for mosquitoes have been known.
Compounds A and B may be used either alone or in combination.

In the mosquito aqueous bait agent, the content of at least one active ingredient selected from compounds A and B is 0.001% by mass with respect to the total mass of the mosquito aqueous bait agent in consideration of the effects of the present invention. The above is preferable, and 0.01% by mass or more is more preferable.
The upper limit is not particularly limited, but is preferably within the range where the active ingredient to be blended can be completely dissolved in the aqueous bait for mosquitoes.
Within the above range, the greater the content of the active ingredient, the faster the effect on mosquitoes. Further, if the content is not more than the upper limit of the above range, the blended active ingredient is completely dissolved in the aqueous bait for mosquitoes, and precipitation does not occur, so the blended active ingredient is effectively used, Economically favorable.

The aqueous bait for mosquitoes can be prepared by dissolving the active ingredient in water.
In the aqueous bait for mosquitoes, the amount of water is appropriately adjusted according to the amount of these components so that the total amount of the active ingredient and the additive that is optionally added is 100% by mass. Usually, it exists in the range of 90-99.999 mass%, and 95-99 mass% is preferable.

The aqueous bait for mosquitoes preferably further contains at least one compound selected from the group consisting of hexose, sugar alcohol and disaccharide (hereinafter, these may be collectively referred to as sugars). This further improves mosquito control efficiency. This is presumably because the sugars attract the mosquito and improve the feeding efficiency of the mosquito.
Examples of hexose include D-fructose (fructose), D-glucose (dextrose), D-galactose and the like.
Examples of the sugar alcohol include D-sorbitol and D-mannitol.
Examples of the disaccharide include maltose and sucrose (sucrose).
Any one of these compounds may be used alone, or two or more thereof may be used in combination.
0.1-10 mass% is preferable with respect to the total mass of the said mosquito aqueous bait agent in the aqueous | water-based mosquito bait agent, and 1-5 mass% is more preferable. The effect by mix | blending saccharides is fully acquired as this content is more than the lower limit of the said range, and it is excellent in eating property as it is below an upper limit.

The aqueous bait for mosquitoes may further contain a solubilizer as long as the effects of the present invention are not impaired. Thereby, content of an active ingredient can be increased.
Examples of the solubilizer include monohydric alcohols, polyhydric alcohols, surfactants, N-methyl-2-pyrrolidone and the like.
As the monohydric alcohol, for example, a monohydric alcohol having 2 to 4 carbon atoms is preferable, and specific examples include ethanol, 1-propanol, 2-propanol and the like.
As the polyhydric alcohol, for example, a polyhydric alcohol having 3 to 9 carbon atoms is preferable, and specific examples include glycerin, 1,3-butanediol, propylene glycol, dipropylene glycol and the like.
Examples of the surfactant include sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene alkyl ether, polyoxyethylene polyoxypropylene alkyl ether, polyglycerin fatty acid ester and the like.
Examples of the sorbitan fatty acid ester include coconut fatty acid sorbitan, sorbitan monolaurate, sorbitan monooleate, and the like.
Examples of the polyoxyethylene sorbitan fatty acid ester include polyoxyethylene (20) coconut oil fatty acid sorbitan, polyoxyethylene (20) sorbitan monolaurate, polyoxyethylene (20) sorbitan monooleate, and polyoxyethylene hydrogenated castor oil. Examples include polyoxyethylene (40) hydrogenated castor oil, polyoxyethylene (50) hydrogenated castor oil, polyoxyethylene (60) hydrogenated castor oil, polyoxyethylene (80) hydrogenated castor oil, and the like.
Examples of the polyoxyethylene alkyl ether include polyoxyethylene lauryl ether and polyoxyethylene oleyl ether.
Examples of the polyoxyethylene polyoxypropylene alkyl ether include polyoxyethylene (20) polyoxypropylene (4) cetyl ether.
Examples of polyglycerin fatty acid esters include polyglyceryl monolaurate.
In the above compounds, the numerical value in () represents the average number of moles of ethylene oxide or propylene oxide added.
The blending amount of the solubilizer is appropriately selected depending on the type thereof, but is preferably 0.01 to 10% by mass, more preferably 0.03 to 5% by mass, based on the total mass of the aqueous mosquito bait agent. 0.05-3 mass% is still more preferable.

The aqueous bait for mosquitoes may further contain other components than the above as necessary, as long as the effects of the present invention are not impaired. The other component is not particularly limited and may be a conventionally known additive. Examples of the additive include preservatives, fragrances, coloring agents, and anti-corrosion agents. Further, if an attractant or a synergist is added, the effect can be further enhanced.
As preservatives, proxel, bronopol, isothiazolinone, methyl paraoxybenzoate, ethyl paraoxybenzoate, cetylpyridinium chloride, benzalkonium chloride, trometamol, sorbic acid, 2-phenoxyethanol, pentanediol, hexanediol, heptanediol, Octanediol or the like may be added.
Any one of these components may be used alone, or two or more thereof may be used in combination.

The method for using the aqueous bait for mosquitoes of the present invention, that is, the method for controlling mosquitoes is not particularly limited, and may be the same as conventional bait agents. For example, a feeding base impregnated with an aqueous bait for mosquitoes may be installed in a place where mosquitoes are to be controlled. When the mosquito eats the mosquito aqueous bait agent, an insecticidal effect on the mosquito is exhibited.
At this time, it is preferable that at least a part of the feeding substrate is exposed to the atmosphere. For example, when the feeding base is completely immersed in the aqueous bait for mosquitoes, there is no scaffold for mooring mosquitoes, so that the feeding efficiency is lowered and a sufficient extermination effect cannot be obtained.
The feeding substrate may be taken out directly after being immersed in an aqueous mosquito bait, and used on a chemical supply body (liquid absorbent core) placed in a container containing the aqueous mosquito bait. It may be placed (at this time, the position of the liquid level of the aqueous bait for mosquitoes is below the upper end of the chemical solution supply body) and moistened via the chemical solution supply body.
The feeding substrate may be any material that can serve as a scaffold to be moored when mosquitoes eat (drink) the aqueous mosquito aqueous bait, such as absorbent cotton, non-woven fabric or woven fabric of natural fibers or synthetic fibers, paper Etc.
Examples of the natural fibers include natural cellulosic fibers such as cotton, pulp and hemp, viscose rayon obtained from pulp, copper ammonium rayon, solvent-spun rayon lyocell, tencelle and other regenerated cellulosic fibers, chitin, Examples include regenerated fibers such as alginic acid fibers and collagen fibers.
Examples of the synthetic fibers include polyolefin fibers, polyester fibers, polyamide fibers, polyacrylonitrile fibers, polyester fibers, polyamide fibers, polyvinyl alcohol fibers, and polyurethane fibers.
As the chemical supply body, the same material as the feeding base can be used.

  The above-mentioned aqueous bait for mosquitoes according to the present invention is a mosquito that does not exhibit feeding repellency, has an oral insecticidal effect, and is excellent in rapid action. For example, mosquitoes can be obtained in a significantly shorter time than boric acids. Demonstrate the lethal effect against. The reason why such an effect is obtained is not clear, but it is presumed that boric acids act on the mosquito's digestive system itself, whereas compounds A and B each act on the nervous system via the digestive tract. . In addition, each of compounds A and B can easily come into contact with the mosquito's leg or mouth when ingested, which may also have the potential to exert a contact effect.

The present invention will be described more specifically with reference to examples. However, the present invention is not limited to these.
In each of the following examples, as the compound A, “trade name: ELEMIC” (powder, purity: methoxadiazone 99.0% or more) manufactured by Sumitomo Chemical Co., Ltd. was used. As Compound B, “Propoxl” (powder, purity: 99.6%) manufactured by Nippon Agricultural Chemicals Co., Ltd. was used.

<Test Example 1>
For each of Compound A, Compound B, and boric acid, aqueous solutions having concentrations shown in Table 1 were prepared. Absorbent cotton was impregnated with each of the aqueous solutions, and was taken once by an adult female of Chikaeka, and the time from when it was taken until when it was knocked down (a state where flight and walking were impossible) was measured. The results are also shown in Table 1.
As shown in Table 1, in the case of boric acid, the knockdown effect was not obtained even when 96 hours passed with a 1% by mass aqueous solution. On the other hand, it was confirmed that the compounds A and B had a knockdown effect within 20 minutes even in 0.01% by mass aqueous solution, and showed a high immediate effect at a lower dose than boric acid.

<Examples 1-4, Comparative Examples 1-3>
Each component shown in Table 2 was mixed to prepare 50 mL of each mosquito aqueous bait agent having the composition shown in Table 2.
In Table 2, the unit of the blending amount is “mass%”, and the “remaining part” of water indicates an amount in which the total amount of the aqueous mosquito bait is 100% by mass.

  For the obtained aqueous bait agents for mosquitoes of Examples 1 to 4 and Comparative Examples 1 to 3, the following evaluations 1 and 2 (feeding tests 1 and 2 for mosquitoes) were performed, respectively.

[Evaluation 1 (Eating test 1 against mosquitoes (forced feeding))]
Fifteen adult females of Chikaeka were introduced into a cage (30 cm × 30 cm × 30 cm).
Absorbent cotton was impregnated with the above-mentioned aqueous bait agent for mosquitoes and placed in a PET container. This container was placed in one place in the cage, and the number of mosquito deaths after a predetermined time (8.5 hours (h), 24 h) was measured.
The same operation was repeated again, and the number of deaths (%) for a total of 30 animals was determined from these results. The results are shown in Table 3.
As shown in Table 3, the aqueous bait for mosquitoes of Examples 1 to 4 containing Compound A or B as an active ingredient was higher in death than Comparative Examples 1 to 3 at any stage of 8.5 h and 24 h. The rate was high and it was excellent in quick effect.

[Evaluation 2 (Feeding test 2 against mosquitoes (optional feeding))]
Fifteen adult females of Chikaeka were introduced into a cage (30 cm × 30 cm × 30 cm).
Absorbent cotton was impregnated with the above-mentioned aqueous bait agent for mosquitoes and placed in a PET container. This container is placed in one place in the cage, and a sucrose aqueous solution (sucrose concentration 1% by mass) is placed in the same container in one place so that mosquitoes can freely select and ingest. The number of mosquito deaths after a predetermined time (8.5 hours (h), 24 h) was measured.
The same operation was repeated again, and the number of deaths (%) for a total of 30 animals was determined from these results. The results are shown in Table 4.
From the results of Table 4 and the results shown in Table 3, the aqueous bait for mosquitoes of Examples 1 and 2 containing Compound A or B as an active ingredient was prepared by using an aqueous sucrose solution so that mosquitoes could freely select and ingest. Even when placed, the mortality rate was as high as when placed (Evaluation 1). From these results, it was confirmed that the compounds A and B have a rapid effect on mosquitoes and that the mosquitoes hardly show feeding repellency.

<Examples 5-7>
Each component shown in Table 5 was mixed to prepare an aqueous mosquito bait.
Each mosquito bait agent was evaluated in the same manner as in the above evaluations 1 and 2, and both showed high rapid efficacy against Chikaeka without showing food repellency.

Claims (2)

  Mosquito containing as active ingredient at least one selected from 5-methoxy-3- (o-methoxyphenyl) -1,3,4-oxadiazol-2 (3H) -one and 2-isopropoxyphenyl methyl carbamate Aqueous bait.   A method for controlling mosquitoes, comprising using the aqueous bait for mosquitoes according to claim 1.