Mosquito attracting method, mosquito attracting gas, and mosquito attracting and capturing device

Abstract

To provide an excellent mosquito attraction method.SOLUTION: A mosquito attraction method uses carbon dioxide. The carbon dioxide contains alcohol to be a concentration of 0.06% or less in volume ratio, which is released to space.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a method for attracting mosquitoes, a mosquito attracting gas, and a mosquito attracting and capturing device. [Background technology]

[0002] In order to protect the body from mosquitoes such as Culex pipiens pallens, which cause damage to the human body through their biting and blood-sucking behavior, insecticide aerosols and heated vaporizers have been developed and are widely used for prevention and extermination purposes.

[0003] On the other hand, mosquito traps have been used in the past to reduce the use of insecticides, reduce the number of mosquitoes in the outdoors, etc. For example, a known technique for such traps is to use carbon dioxide gas to attract, kill, and capture mosquitoes. Patent Document 1 discloses a mosquito trap that attracts mosquitoes with an attractant gas generating means that generates carbon dioxide gas, and captures the attracted mosquitoes with an adhesive. Patent Document 2 discloses a simple mosquito trap that attracts and kills mosquitoes by applying electricity to an electric heater to heat a chemical solution in which a mosquito-killing component and carbon dioxide gas are mixed with alcohol. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 10-229801 [Patent Document 2] Utility Model Registration No. 3144480 Summary of the Invention [Problem to be solved by the invention]

[0005] As mentioned above, carbon dioxide is known as an attractant used to trap mosquitoes, but carbon dioxide alone is not effective enough to attract mosquitoes. Therefore, attempts have been made to improve the mosquito attraction by using carbon dioxide in combination with alcohol, but the effect is still not sufficient and there is still room for improvement. Therefore, an object of the present invention is to provide an excellent method for attracting mosquitoes that can sufficiently attract mosquitoes even under natural conditions, not just when a heating means is used. [Means for solving the problem]

[0006] As a result of extensive research, the inventors discovered that by using carbon dioxide and alcohol in combination, and under specific conditions, a synergistic attractant effect on mosquitoes can be achieved, leading to the completion of the present invention.

[0007] That is, the present invention is characterized by the following (1) to (4). (1) A method for attracting mosquitoes using carbon dioxide gas, A method for attracting mosquitoes, characterized in that the carbon dioxide gas contains alcohol at a concentration of 0.06% or less by volume and is released into space. (2) The method for attracting mosquitoes according to (1) above, wherein the carbon dioxide gas contains alcohol at a concentration of 0.0025 to 0.03% by volume. (3) Mosquito attractant gas containing not more than 0.06% alcohol by volume in carbon dioxide gas. (4) A mosquito attractant gas generator that generates the mosquito attractant gas described in (3) above; a mosquito attracting gas release unit that releases the generated mosquito attracting gas into space; a mosquito trapping unit that traps mosquitoes; A mosquito attracting and capturing device. [Effects of the Invention]

[0008] The mosquito attracting method of the present invention uses carbon dioxide and alcohol in combination under specific conditions, which acts synergistically on mosquitoes. This provides an excellent attracting effect on mosquitoes, allowing for efficient capture of mosquitoes. Furthermore, this synergistic effect induces probing behavior in mosquitoes. This increases the time that attracted mosquitoes remain in the area, thereby improving the mosquito capture effect. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a schematic diagram showing the configuration of a mosquito attracting and capturing device according to one embodiment of the present invention. [Figure 2] FIG. 2 is a schematic diagram showing the configuration of the test device used in Test Example 1. [Figure 3] FIG. 3 is a schematic diagram showing the configuration of the test device used in Test Example 2. [Figure 4] FIG. 4 is a graph showing the cumulative number of test insects in Test Example 2. [Figure 5] FIG. 5 is a graph showing the number of test insects that performed the probe behavior in Test Example 2. DETAILED DESCRIPTION OF THE INVENTION

[0010] The mosquito attracting method, mosquito attracting gas, and mosquito attracting and capturing device of the present invention will be described in detail below.

[0011] (Method of attracting mosquitoes) The method for attracting mosquitoes using carbon dioxide gas of the present invention is characterized in that carbon dioxide gas is mixed with alcohol at a concentration of 0.06% or less by volume and released into a space.

[0012] The mosquito attracting method of the present invention is based on the discovery that by adding alcohol to carbon dioxide gas at a specific concentration range of 0.06% or less by volume and releasing it into air, it exerts a particularly effective attractant effect on mosquitoes. In addition, the mosquito attracting method of the present invention is based on the discovery that by adding alcohol in a specific concentration range of 0.06% or less by volume to carbon dioxide gas and releasing it into the air, it strongly induces probing behavior, one of the blood-sucking behaviors of mosquitoes (the behavior of determining a blood-sucking site and inserting the probing needle).

[0013] The type of alcohol used in the mosquito attracting method of the present invention is not particularly limited, and examples include ethanol, methanol, 1-octen-3-ol, 1-hepten-3-ol, etc. These may be used alone or in combination. Among them, ethanol is preferred from the viewpoints of attracting mosquitoes and inducing probing behavior.

[0014] In the mosquito attracting method of the present invention, it is important that the alcohol concentration in the carbon dioxide gas is 0.06% or less by volume. The inventors have found that when the alcohol concentration in the carbon dioxide gas is 0.06% or less by volume, the carbon dioxide gas and the alcohol act synergistically, resulting in superior mosquito attracting and probe-attracting effects compared to when carbon dioxide gas is used alone. Furthermore, they have found that when the alcohol concentration in the carbon dioxide gas exceeds 0.06% by volume, the mosquito attracting effect of the carbon dioxide gas is reduced and a mosquito repellent effect may occur. The alcohol concentration in the carbon dioxide gas is preferably 0.0025 to 0.06% by volume, more preferably 0.0025 to 0.03%, and even more preferably 0.005 to 0.015%, from the viewpoint of attracting mosquitoes and inducing probing behavior.

[0015] The alcohol concentration in carbon dioxide gas can be adjusted appropriately within a range of 0.06% or less by volume depending on the method for generating carbon dioxide gas. For example, as will be described later in the Examples, in a method for generating carbon dioxide gas using citric acid and sodium bicarbonate, the alcohol concentration in carbon dioxide gas can be adjusted by appropriately adjusting the alcohol concentration in the citric acid solution, the cumulative amount of the citric acid solution reacted with sodium bicarbonate, the dropwise addition rate of the citric acid solution, etc.

[0016] The method for measuring the alcohol concentration (volume ratio) in carbon dioxide gas is not particularly limited, and any conventionally known method can be used. For example, the carbon dioxide gas can be measured by collecting it in a gas collection bag such as a sampling bag, and then collecting the carbon dioxide gas with a gas sampler connected to a detector tube.

[0017] In the mosquito attracting method of the present invention, other known additives such as attractants, insecticides, antibacterial agents, colorants, ultraviolet absorbers, retention agents, lubricants, and solvents can be added to the carbon dioxide gas or the carbon dioxide gas generating source, as long as they do not impair the mosquito attracting effect and the probe attracting effect. If the additive contains alcohol, the alcohol concentration in the carbon dioxide gas as a whole should not exceed 0.06% by volume.

[0018] Other attractant components include, for example, alcoholic beverages such as brandy, whiskey, rum, vodka, shochu, and sake; brewed vinegars such as black vinegar, red vinegar, table vinegar, apple vinegar, and rice vinegar; sugars such as honey, liquid sugar, and maple syrup; lactic acid products such as lactic acid drinks, yogurt, and cheese; fruit juice; and fruit-like flavorings.

[0019] Examples of insecticidal components include dichlorvos, fenitrothion, IBTA, IBTE, transfluthrin, metoflustone, profluthrin, empenthrin, propoxur, fenobucarb, amidoflumet, dinotefuran, fipronil, hydramethylnon, carbaryl, and boric acid.

[0020] Examples of antibacterial ingredients include chlorine dioxide, iodine, thymol, isopropylmethylphenol, formaldehyde, glutaraldehyde, ethanol, propyl alcohol, phenol, cresol, phenoxyethanol, cetylpyridinium chloride, and parabens.

[0021] Examples of colorants include Blue No. 1 and Yellow No. 4.

[0022] Examples of ultraviolet absorbers include trisresorcinol triazine compounds.

[0023] Examples of the solvent include lower alcohols such as methanol, ethanol, and propanol; hydrocarbon solvents such as liquid paraffin; and water such as distilled water, tap water, and deionized water.

[0024] In the method for attracting mosquitoes of the present invention, the specific method for releasing the alcohol-containing carbon dioxide gas into the air is not particularly limited. The method for attracting mosquitoes of the present invention will be specifically described below using examples, but the present invention is not limited to the following embodiments.

[0025] Any conventionally known method can be used to generate carbon dioxide gas, but here, a method of generating carbon dioxide gas using citric acid and sodium hydrogen carbonate will be described as an example.

[0026] First, an alcohol-containing citric acid solution is prepared. The alcohol content in the citric acid solution is adjusted appropriately so that the alcohol concentration in the carbon dioxide gas is 0.06% or less by volume when carbon dioxide gas, which will be described later, is released into the space. This is adjusted appropriately depending on the alcohol concentration in the citric acid solution, the cumulative amount of citric acid solution reacted with sodium bicarbonate, the dripping rate of the citric acid solution, etc., as will be described later in the Examples.

[0027] Next, the alcohol-containing citric acid solution is added dropwise to the sodium bicarbonate. The rate of addition can be adjusted appropriately depending on the desired alcohol concentration in the carbon dioxide gas, but is, for example, 0.25 to 3 mL / min. The reaction between the alcohol-containing citric acid solution and the sodium bicarbonate generates a predetermined amount of alcohol-containing carbon dioxide gas. For example, when ethanol is used as the alcohol, 2 L of a 1 molar citric acid solution containing 0.1% ethanol by volume is dripped into a sodium bicarbonate tank filled with 6 molar sodium bicarbonate at a rate of 1.5 mL / min, and carbon dioxide containing ethanol at a concentration that is theoretically effective in attracting mosquitoes can be released at a rate of approximately 100 mL / min through a tube connected to the sodium bicarbonate tank for approximately 22 hours.

[0028] The means for releasing the alcohol-containing carbon dioxide gas into space may be, for example, a tube that moves the generated mosquito attractant gas to a predetermined location and releases the gas into space, an air stone that releases the mosquito attractant gas into space, or a fan that blows air to release the mosquito attractant gas into space.

[0029] (mosquito attractant gas) The carbon dioxide gas generated by the above-mentioned mosquito attracting method contains 0.06% or less alcohol by volume, has the effect of strongly attracting mosquitoes, and functions as a mosquito attractant gas (also called a mosquito attractant gas composition). The mosquito attractant gas may contain the above-mentioned additives in addition to carbon dioxide gas and alcohol.

[0030] (Mosquito trapping device) The mosquito attracting and capturing device of the present invention is equipped with a mosquito attracting gas generator that contains 0.06% or less alcohol by volume in carbon dioxide gas. The form of the device is not particularly limited as long as it can generate the mosquito attracting gas.

[0031] One aspect of the mosquito attraction and capture device of the present invention comprises a mosquito attracting gas generation unit that generates mosquito attracting gas, a mosquito attracting gas emission unit that releases the generated mosquito attracting gas into space, and a mosquito capture unit that captures mosquitoes.

[0032] 1, the mosquito attractant gas generation unit may include, for example, a citric acid solution tank 11 filled with a citric acid solution 111, a dripping unit 12 for dripping the citric acid solution 111 into sodium bicarbonate 131, and a sodium bicarbonate tank 13 filled with sodium bicarbonate 131. The dripping speed of the citric acid solution 111 is adjusted by the dripping unit 12. Citric acid solution 111 in citric acid solution tank 11 is dripped through dripping section 12 onto sodium bicarbonate 131 in sodium bicarbonate tank 13, thereby generating mosquito attractant gas.

[0033] The mosquito attractant gas emission unit may include, for example, a tube 14 that moves the generated mosquito attractant gas to a predetermined location, and an air stone 15 that emits the mosquito attractant gas, as shown in Figure 1. The mosquito attractant gas generated from the mosquito attractant gas generation unit passes through tube 14 and is emitted from air stone 15 into the air.

[0034] The mosquito trapping unit may be, for example, a trap 16 that traps the attracted mosquitoes, as shown in Figure 1. Trap 16 may be a conventionally known trap, such as a trap with an adhesive sheet or a trap that uses a suction fan to suck in and trap mosquitoes by the gravitational force of the wind.

[0035] In addition, in the mosquito attracting and capturing device of the present invention, the trap 16 may contain a mosquito-killing component in order to kill the mosquitoes attracted by the mosquito attractant gas within the trap 16.

[0036] Mosquitoes to be attracted in the present invention include, for example, Aedes albopictus, Aedes aegypti, and other mosquitoes, Culex pipiens, Culex quinquefasciatinus, Culex quinquefasciatinus, and Culex molestus, and Anopheles, but are not limited to these exemplified mosquitoes. [Example]

[0037] The present invention will be further explained below based on specific test examples, but the present invention is not limited to the following examples in any way.

[0038] (Test Example 1) In this test, the relationship between the ethanol concentration in the citric acid solution and the ethanol concentration in the generated carbon dioxide gas was confirmed in a carbon dioxide gas generation system.

[0039] (Test Method) The test method will be explained using Figure 2. 1. 1000 mL of citric acid solution 211 was prepared so that the citric acid concentration was 1 mol / L (192 g / L) and the ethanol concentration was 0.1 v / v%, 0.3 v / v%, 1 v / v%, 3 v / v%, or 10 v / v%. 2. 1000 mL of the citric acid solution 211 prepared above was filled into a 5 L citric acid solution tank 21. Furthermore, 3 moles (252 g) of sodium bicarbonate 231 was filled into a 5 L sodium bicarbonate tank 23. Then, first, the citric acid solution 211 in the initial citric acid solution dripping amount shown in Table 1 was dripped into the sodium bicarbonate 231 via the dripping unit 22. Thereafter, the citric acid solution 211 was dripped into the sodium bicarbonate 231 at a rate of 1.5 mL / min for 10 minutes, generating carbon dioxide gas containing ethanol (mosquito attractant gas). 3. The generated carbon dioxide gas was allowed to flow through a 1 m long tube 24a into a 1 L capacity Tedlar bag 25 at a rate of approximately 100 mL / min for 10 minutes. Then, 100 mL of the carbon dioxide gas collected in the Tedlar bag 25 was collected using a gas sampler (manufactured by Gastec Co., Ltd.) connected to a detector tube through an 18 cm long tube 24b, and the ethanol concentration in the generated carbon dioxide gas was measured.

[0040] Table 1 shows the relationship between the ethanol concentration in the citric acid solution, the cumulative amount of citric acid solution added, and the ethanol concentration in the released carbon dioxide gas. In Table 1, "initial amount of citric acid solution added" refers to the amount of citric acid solution added dropwise to sodium bicarbonate in advance, and "dropping rate x dropping time" refers to the dropping rate and time when citric acid solution is added dropwise to sodium bicarbonate after a predetermined amount of citric acid solution has been added dropwise.

[0041] [Table 1]

[0042] (Test Example 2) In this test, we confirmed the relationship between the ethanol concentration in the carbon dioxide generated by the carbon dioxide generation system and the attractant activity and induction of probing behavior against Aedes albopictus.

[0043] (Test Method) The test method will be explained using Figure 3. 1. The test insects used were female adult Aedes albopictus mosquitoes 16 to 19 days after emergence (selected as those with a high desire to feed on blood). 2. Six hundred test insects that showed a desire to suck blood when placed on the side of the rearing cage were selected with an insect aspirator and placed in a stainless steel test cage 36 (25 cm cube, 16 mesh) for acclimatization. 3. 1000 mL of citric acid solution 311 was prepared so that the citric acid concentration was 1 mol / L (192 g / L) and the ethanol concentration was 0 v / v%, 0.1 v / v%, 0.3 v / v%, 1 v / v%, 3 v / v%, or 10 v / v%. 4. The citric acid solution 311 was filled into a 5 L citric acid solution tank 31. Also, 3 moles (252 g) of sodium bicarbonate 331 was filled into a 5 L sodium bicarbonate tank 33. Then, first, the citric acid solution 311 was added dropwise to the sodium bicarbonate 331 in the initial citric acid solution dropping amount shown in Table 2 via the dropping part 32. Thereafter, the citric acid solution 311 was added dropwise to the sodium bicarbonate 331 at a rate of 1.5 mL / min for 10 minutes to generate carbon dioxide gas. 5. The generated carbon dioxide gas was passed through a 1-m-long tube 34 and flowed into an air stone 35 (circular, 10.8 cm in diameter, 1.9 cm thick) at a rate of approximately 100 mL / min. Carbon dioxide gas was then released from the air stone 35 and administered to the test insects in a test cage 36 (under dark conditions). 6. The number of test insects flying onto the air stone 35 was observed every 30 seconds from the start of the test until 10 minutes had passed, and the cumulative number of flying insects up to 10 minutes was calculated. The number of test insects that performed the probe behavior was also calculated. The test was repeated three times, and the average results were calculated.

[0044] The results of the cumulative number of insects that flew in are shown in Table 2 and Figure 4. The results of the number of test insects that performed the probe behavior are shown in Table 2 and Figure 5. Note that the "ethanol concentration (%) in the released carbon dioxide gas" in Table 2 is based on the relationship between the ethanol concentration in the citric acid solution, the cumulative amount of citric acid solution dripped, and the ethanol concentration in the released carbon dioxide gas, as confirmed in Test Example 1 above.

[0045] [Table 2]

[0046] As shown in Table 2 and Figures 4 and 5, when carbon dioxide gas containing ethanol at a volumetric concentration of 0.06% or less was released into the air, the cumulative number of mosquitoes flying was higher and the mosquitoes exhibited stronger probing behavior than when carbon dioxide gas containing no ethanol was released into the air. Furthermore, it was found that when the concentration of ethanol in the carbon dioxide gas exceeded 0.06% in terms of the solution ratio, the cumulative number of mosquitoes flying in was lower and the mosquitoes' probing behavior was weakened compared to when carbon dioxide gas containing no ethanol was released into the air.

[0047] (Test Example 3) The mosquito attracting effect and probing behavior eliciting effect of carbon dioxide gas containing ethanol on mosquitoes living outdoors were confirmed using the same method as in Test Example 2 above. (Test Method) The test was conducted in the same manner as in Test Example 2, except that the test location was a park where Aedes albopictus inhabits outdoors (temperature and humidity during the test period: approximately 26°C / approximately 75% RH) and the target was Aedes albopictus inhabiting outdoors. During observations up to 30 minutes after the start of the test, the attraction activity and probe activity of Aedes albopictus to the air stone, which is a carbon dioxide release port, were observed and evaluated according to the following criteria. <Evaluation> ++ (Strong activity): Mosquitoes are observed flying onto the air stone, and strong probing behavior is also observed. + (active): Mosquitoes are observed flying onto the air stone, but no probing behavior is observed. -: (No activity): No mosquitoes were observed flying onto the air stone, and no probing behavior was observed.

[0048] The results of the attractant activity and probe activity are shown in Table 3. The "ethanol concentration (%) in the released carbon dioxide gas" in Table 3 was calculated by the same test as in Test Example 1 above.

[0049] [Table 3]

[0050] As shown in Table 3, carbon dioxide generated in a citric acid solution without adding ethanol was observed to have attractant activity against Aedes albopictus, but no probe activity was observed. When the ethanol concentration in carbon dioxide gas was set to 0.013% by volume, strong attractant and probing activity against Aedes albopictus was observed. When the ethanol concentration in carbon dioxide gas was set to 0.09% by volume, no attractant or probing activity was observed against Aedes albopictus. Therefore, it was found that the method of the present invention, in which ethanol is added to carbon dioxide gas at a volumetric concentration of 0.06% or less and then released into air, can attract and induce probing behavior in mosquitoes even outdoors. [Explanation of symbols]

[0051] 10 Mosquito trapping device 11, 21, 31 Citric acid solution tank 111, 211, 311 Citric acid solution 12, 22, 32 dripping part 13, 23, 33 Sodium bicarbonate bath 131, 231, 331 Sodium bicarbonate 14, 24a, 24b, 34 tubes 15, 35 Air Stone 25 Tedlar Bag 16 Trap 36 Test Cage

Claims

1. A method for attracting mosquitoes using carbon dioxide gas, comprising: A method for attracting mosquitoes, comprising adding dropwise a citric acid solution containing ethanol to sodium bicarbonate to adjust the concentration of ethanol in the carbon dioxide gas to 0.0025% to 0.06% by volume, and releasing the resulting mixture into a space.

2. 2. The method for attracting mosquitoes according to claim 1, wherein the carbon dioxide gas contains ethanol at a concentration of 0.0025 to 0.03% by volume.

3. A mosquito attractant gas generator that generates a mosquito attractant gas adjusted to a concentration of 0.0025 to 0.06% by volume of ethanol in carbon dioxide by dropping a citric acid solution containing ethanol into sodium bicarbonate; a mosquito attracting gas release unit that releases the generated mosquito attracting gas into space; a mosquito trapping unit that traps mosquitoes; A mosquito attracting and capturing device.

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