JPH0680510A - Insect pest exterminating material - Google Patents

Abstract

PURPOSE:To obtain an insect pest exterminating material capable of stably manifesting insect pest exterminating effects thereof in the insect pest exterminating material capable of physically exterminating the insect pests with diatomaceous earth. CONSTITUTION:The objective infect pest exterminating material is insect pest exterminating materials 41, 42, 43, 81, 82 and 83, composed of a solid substance containing powdery diatomaceous earth having a smaller particle diameter than the interval dimensions (P) of body hair 3 of each insect pest 1 which is an object of extermination and silica gel added thereto and applied to the insect pest 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pest control material.

[0002]

2. Description of the Related Art Termites, clawed mites, etc.,
When controlling pests, it is common to use chemical insecticides.For example, for the purpose of controlling termites and mites, chemical insecticides with strong acute toxicity such as organophosphorus drugs and pyrethroid drugs are used. Widely used.

[0003]

By the way, chemical insecticides of this kind are intended to exterminate harmful insects by the chemical effects of their chemical components, but their chemical components often have an adverse effect on humans and animals. There is also concern about environmental pollution caused by the spraying of highly toxic chemical substances.

With the use of chemical insecticides, pests are gradually provided with insecticide resistance (resistance), and the initially effective chemical insecticide eventually loses its effect as an insecticide. Happens.

From such a background, the inventor of the present application, as a result of diligent research using various substances having low toxicity, found that diatomaceous earth has a physical pest control effect described later.

In the pest control material using such diatomaceous earth, it is important for the diatomaceous earth to be in the form of powder in order to exert its pest control effect. The diatomaceous earth, which is lumpy, tends to become lumpy by adsorbing water and its pest control effect is reduced.

The present invention has been made under such circumstances, and an object thereof is to provide a stable pest control effect in a pest control material which physically controls pests using diatomaceous earth. Is.

[0008]

In order to achieve this object, the invention according to claim 1 is a pest control material which is made of a solid matter and adheres to pests, wherein the solid matter has a particle size thereof. Is characterized in that it contains a powdery diatomaceous earth smaller than the distance between the hairs of the pests to be exterminated, and that it has a hygroscopic substance added thereto.

[0009]

According to the invention described in claim 1, since a substance having a hygroscopic property is added to the pest control material in addition to the powdery diatomaceous earth, moisture such as moisture becomes a substance having a hygroscopic property. It is reduced that the powdery diatomaceous earth becomes lumpy by being adsorbed, and the diatomaceous earth can maintain the powdery state.

Therefore, the diatomaceous earth, which is powdery and has a particle size smaller than the distance between the hairs of the pests to be exterminated, easily adheres to the pests without being hindered by the body hairs of the pests, thereby stabilizing the pest extermination effect. Can be demonstrated.

[0011]

EXAMPLES The present invention will be described below with reference to examples with reference to the drawings. First, the pest control effect of diatomaceous earth will be described.

According to the research conducted by the inventor of the present application, it is considered that the physical pest control effect of diatomaceous earth is caused by the following two mechanisms.

First, the first mechanism will be described with reference to FIG.

FIG. 1 is a schematic plan view of the body surface of the pest, where 1 is the pest, 2 is the skin on the body surface of the pest, 3 is the hair of the pest, and 41, 42, 43, 44 are powdery. It is a pest control material composed of diatomaceous earth.

The pest 1 takes in oxygen into the body through the stigma (not shown) or the skin 2, and discharges carbon dioxide to the outside of the body directly through the skin 2.

A plurality of body hairs 3 are formed in a scattered manner on the skin 2 which discharges carbon dioxide gas in this way.

The body hairs 3 are formed at predetermined positions according to the type of the pests 1, and the distance between the body hairs 3 is different. However, in consideration of various pests. If it is standardized as a standard, the arrangement of the body hairs 3 on the skin 2 of the pest 1 is as shown in FIG. 1, and the spacing dimension P of each body hair 3 is assumed to be uniform for simplification of the following description.

Further, pest control materials 41, 4 made of diatomaceous earth
Although 2, 43 and 44 actually have various shapes in reality, in order to simplify the explanation of the mechanism below, they are shown as circles in the drawings, and they are different only in their particle size.

The skin 2 on which the body hair 3 is formed in this way
The state of adhesion of the pest control materials 41, 42, 43, 44 on the top is as follows.

That is, the pest control material 41 has a particle size D
₁ is slightly smaller than the space dimension P of the body hair 3, but is almost the same.

Therefore, the pest control material 41 can reach the skin 2 of the pest 1 through the gap between the body hairs 3.

Then, the pest control material 41 that reaches the skin 2 of the pest 1 adheres to the skin 2 due to lipids and water on the skin 2.

As a result, the part of the skin 2 located below the pest control material 41 is prevented from discharging carbon dioxide gas from its surface. In the case of a harmful insect that takes in oxygen from the skin 2, the harmful insect exterminating material 41 also prevents the intake of oxygen from the skin 2 at the site at the same time.

The pest control material 42 has a particle diameter D ₂ smaller than that of the pest control material 41, and the pest control material 43 has a particle diameter further smaller than the particle diameter D ₂ of the pest control material 42.

The pest control materials 42 and 43 having a smaller particle size than the pest control material 41 can reach the skin 2 of the pest 1 without being obstructed by the body hair 3 as apparent from FIG. The same as the pest control material 41, the skin 2
It adheres to the top and interferes with the carbon dioxide emission of the pest 1.

The pest control material 44 is a comparative example in this example, and its particle diameter D ₄ is larger than the interval dimension P of the body hairs 3. As is apparent from FIG. 1, the pest control material 44 having such a particle size will prevent any of the body hairs 3 from adhering to the pest control material 41, 42, 43 from the skin 2 of the pest 1 as described above. It is not possible to prevent the carbon dioxide emission effect of the above.

When the attachment of the pest control materials 41, 42, 43 impedes the discharge of carbon dioxide gas from the skin 2 at that portion, the respiratory action of the pest 1 depends on the area of the attached portion. If the function deteriorates and the area of that part exceeds the allowable range, respiratory failure will occur, and eventually the pest 1 will die.

Therefore, when pest control is performed using such a pest control material, it is extremely important to enlarge the area where the pest control materials 41, 42 and 43 adhere to the skin 2 and the pest control is performed. By appropriately selecting the particle size of the material according to the pest, the purpose of controlling the pest can be achieved through the expansion of the adhesion area.

Next, the second mechanism will be described with reference to FIG. 2, but the second mechanism is limited to the case where the pest to be exterminated has a stigma.

FIG. 2 schematically shows a cross section of the pest at the stigma, 1 is a pest having stomata, 2 is a body surface of the pest,
3 is the hair of the pest.

In the pest 1 having a stigma, the trachea 5 extending from the body of the pest 1 opens to the body surface 2 and the stomata 6
And the trachea 5 and the gate 6 constitute the trachea system 7 of the pest 1. The trachea system 7 functions as a passage for introducing oxygen taken into the body by the pest 1 into the body. I have.

In the pest 1 having such an air gate 6, the distance between the hairs 3 near the air gate 6 is set to P, and the air gate 6
Let W be the opening size (diameter) of.

Then, in FIG. 2, 81, 82, 8
3 and 84 are pest control materials made of powdery diatomaceous earth, and these pest control materials 81, 82, 83 and 84 are of course actually in various shapes, but the explanation of the mechanism below is simple. In order to make it uniform, it is shown as a spherical shape in the drawings, and each of them is different only in its particle size.

The behavior of the pest control materials 81, 82, 83, 84 in the vicinity of the air gate 6 of the pest 1 differs depending on the particle size thereof, and the pest control materials 81, 8 will be described below.
2,83 function as an active ingredient, and the pest control material 84 is positioned as a comparative example.

That is, the pest control material 81 has a particle diameter D ₅
Is smaller than the space dimension P of the hair 3 and larger than the opening dimension W of the ostium 6.

Therefore, the pest control material 81 can reach the body surface 2 of the pest 1 through the gap of the body hair 3 and be located on the surface side of the air gate 6. The pest control material 81 reaching the body surface 2 of the pest 1 is attached to the body surface 2 due to the lipids and water on the body surface 2, and the air gates 6 are covered with the pest control material 81. It is occluded, and the uptake of oxygen from the air gate 6 is blocked.

The pest control material 82 has a particle diameter D ₆ of 3
It is slightly smaller than the interval dimension P and the opening dimension W of the air gate 6.

Therefore, the pesticidal material 82 reaches the body surface 2 of the pest 1 like the pesticidal material 81, but can further penetrate into the trachea 5 from the air gate 6.

When the pest control material 82 enters the trachea 5,
Since the ventilation area of the trachea 5 is significantly reduced, the uptake of oxygen by the pests 1 is impaired, and the invading pest control material 82 does not easily fall off from the trachea 5, so that the pests 1 are finally depleted by long-term deprivation of oxygen. Will definitely die.

In the pest control material 83 having a particle size smaller than that of the pest control material 82, the body hair 3 hardly causes any obstacle when the pest control material 83 reaches the body surface 2 of the pest 1. In addition, the air gate 6 is also a pest control material 8
Since the size is considerably larger than 3, the pest control material 83 can penetrate into the trachea 5 with a relatively high probability.

In the pest control material 83 thus entering the trachea 5, it is difficult to close the trachea 5 with only a single particle like the pest control material 82, but as described above, it is relatively high. Since it enters the trachea 5 with a probability, a plurality of pest control materials 83 are attached and accumulated, so that the ventilation cross-sectional area of the trachea 5 becomes small, and the pest 1 becomes in an oxygen-deficient state.

The pest control material 84 is a comparative example in the case of the pest 1, and its particle diameter D ₇ is larger than the interval dimension P of the body hairs 3.

In such a case, the pest control material 84 is the body hair 3
As it cannot reach the body surface 2 of the pest 1 due to
Can not be expected to block function. But,
The space dimension P of the body hair 3 and the opening dimension W of the ostium 6 are
Since the value varies depending on the type of pest, depending on the type of pest, the pest control material 84 is the pest control material 81 to
It can act as the equivalent of 83.

Thus, in the case described above, the pest control materials 81, 82, 83 adhere to the tracheal system 7 of the pest 1 and hinder the intake of oxygen from the air gate 6 of the pest 1.
Pest 1 dies due to lack of oxygen and achieves the purpose of pest control.

The advantage common to both the first and second mechanisms is that unlike the conventional insecticides using chemical insecticides, highly acutely toxic chemical substances are evaporated into the space in which pests should be controlled. It is possible to exterminate pests without causing them to be affected, and as a result, it is possible to avoid the influence of chemical pesticides on humans and livestock and environmental pollution, and the pests do not gradually become resistant, and the physical properties of powdery solids Since it is carried out by nature, it is possible to control pests for a long period of time.

Next, a demonstration test of the pest control mechanism will be described.

In this proof test, a petri dish was covered with paper, and
A pest control material composed of powdered diatomaceous earth is evenly spread on this paper, and 10 pests are placed in a petri dish in this state to observe the pest activity state over time.

In the verification test described below, a termite termite worker ant is used as a pest. In this case, the distance P between the body hairs is about 63 μm, and the opening size W of the ostium is about 30 μm.

In the case described below,
It uses diatomaceous earth as a pest control material, and diatomaceous earth consists of siliceous sedimentary rocks formed by depositing the remains of diatoms on the seabed and also contains clay, volcanic ash, and organic matter.

The diatomaceous earth used in the following is "Radiolite # 500" (trade name) manufactured by Showa Chemical Industry Co., Ltd.
The particle size distribution is as shown in FIG.

This pest control material has a weight of about 80
The particle size of% is smaller than the interval size P of the body hair of the termite worker,
The pest control material 4 is an active ingredient in the mechanism of
It is equivalent to 2,43.

Further, approximately 80% or more of this pest control material is an active ingredient in the second mechanism described above, but as is clear from FIG. It is an active ingredient smaller than the opening dimension W of 30 μm and corresponding to the pest control materials 82 and 83 by the second mechanism.

The petri dish used in this verification test was
The diameter is 9 cm, and the pest control material is 0.64 g (100 g / m
It corresponds to the state in which the pest control material is sprayed at a ratio of ² ).

The observation results are as follows.

One hour after the introduction of termites into a Petri dish in which diatomaceous earth was placed as a pest control material,
The ten termites that were thrown in survived by attaching diatomaceous earth as a pest control material to the surface of the body, and all ten survived, eight of them were moving, and the remaining two had antennae and legs fluttering.

Two hours after the introduction of the termites, 10 animals were alive, and all 10 animals had their antennae and legs flapping.

Three hours after the termites were put in, two animals died, and the remaining seven animals had their antennae and legs moved occasionally,
The other one had its antennae and legs flapping.

Four hours after the introduction of the termites, eight animals had died, and the remaining two animals had their legs flapping. At this point, the pest control effect of the pest control material made of diatomaceous earth was confirmed, so the test was terminated.

Microscopic observation of the dead termites revealed that the powdery pest control material was attached to the skin on the body surface of the termites, including the part of the spiracles.

In consideration of the fact that the dead termites contained a large amount of powdery pesticidal material on the body surface, including the part of the spiracle, as a result of observation with this microscope, It can be presumed that the termites died of carbon dioxide emission from the skin 2 by the first mechanism or died due to the lack of oxygen by the second mechanism, and the pest control mechanism was demonstrated. it is conceivable that.

As described above, the first and second mechanisms demonstrated in the powdery diatomaceous earth against termites as pests are the particle size and the control of the powdery diatomaceous earth which is the pest control material as described above. It can be used for various pests because it is physically established in relation to the interval size P of the hair 3 of the target pest 1 or the opening size W of the air gate 6.

Pests that can be exterminated using the pest control material of the present invention include, for example, not only other termites and house mites such as phytoseiid mites, dust mites, mites and cockroaches, but also mosquitoes. , Flies,
Fleas, lice, flat beetles, beetles,
Nostidae moth, sawtooth flat beetle, stag beetle, weevils, adzuki bean weevils, stag beetles, beetles, beetles, squids, midges,
Butterfly flies, stink bugs, flies, ticks, sand flies, green squirrels, plant hoppers, leafhoppers, green leaf moths, white-spotted moths, stag beetles, scale insects, spider mites, aphids, diamondback moths, bollworms , Bark beetles, scarab beetles, white-spotted beetles, grasshoppers and the like.

Among the above-mentioned pests, the house mite dust mites and mites mite have no stigmas and take in oxygen from the skin 2. Therefore, the pest control material of the present invention was used. If the second mechanism does not work,
The diatomaceous earth adhered to the skin by the first mechanism can inhibit not only the emission of carbon dioxide gas but also the uptake of oxygen, whereby the extermination thereof can be reliably performed.

When the above-mentioned pests different from termites are targeted, the pests are selected according to the distance P between the hairs of the target pests, etc., as is clear from the first and second mechanisms described above. Since the particle size of the active ingredient of the pest control material is determined, it is preferable to appropriately adjust the particle size distribution of the pest control material to be used, in the case of pest control material to be a specific type of pest control target, in the case of the pest Body hair spacing P
It is effective to separate only those having a smaller particle size and use this as a pest control material.

For example, when the house tick mites of the house mite are to be exterminated, the distance between the hairs is about 30 μm.

Using the above-mentioned pest control material (having a particle size distribution shown in FIG. 3) made of diatomaceous earth and used for termites as a target for such tick ticks, the pest mites show a weight percent of less than 45% on the skin of the tick ticks. Although it functions as a reachable active ingredient, the remaining 55% or more is equivalent to the pest control material 44 and does not function as a pest control material and is wasted.

Further, the opening size W of the tick of the tick tick is about
Since it is 1 μm, the active ingredient capable of functioning as the pest control materials 82 and 83 in the second mechanism is hardly contained in the pest control material made of diatomaceous earth.

Therefore, in this case, the particle size distribution of the pest control material to be used is adjusted to have a large amount of fine particles, and the pest body hairs 3 having an interval size P, that is, a particle size larger than 30 μm are excluded. In that case, the pest control material to be used is less wasteful, and the probability that the pest control material adheres to the skin of the ticks increases, so the pest control effect becomes more remarkable.

The diatomaceous earth which controls pests by such a mechanism is inevitably required to be in the form of powder having a small particle size. Such a diatomaceous earth in the form of powder is physically hygroscopic and has a diatomaceous earth content. Since powdery diatomaceous earth often contains organic matter, diatomaceous earth in powder form tends to be particularly lumpy when it absorbs moisture.

In the case of agglomerated diatomaceous earth, it is clear that the first and second mechanisms do not function effectively.

Therefore, in the present application, a substance having a hygroscopic property is added to the pest control material containing the diatomaceous earth,
The functions of the first and second mechanisms of diatomaceous earth are to be stably ensured.

The term "hygroscopicity" as used in the present invention is a broad concept including humidity control, and it may be not only a substance having hygroscopicity, but also silica gel, silicic acid anhydride or the like.

The substance having such hygroscopicity may be added to the pest control material containing powdery diatomaceous earth in the form of block or pellet,
Like the diatomaceous earth, it is preferably made into a powder form and mixed with the diatomaceous earth and added. This is because the moisture absorption of the powdery diatomaceous earth, which is the active ingredient, can be uniformly reduced as a whole.

From this point of view, an example in which powdery silica gel as a hygroscopic substance is mixed with the diatomaceous earth and added will be described below.

The silica gel used in this example was obtained by pulverizing "Fuji Home Gel G" (trade name) manufactured by Fuji Davison Chemical Co., Ltd. into a powder form, and its particle size distribution is as shown in FIG. Is.

The pest control material as an example of the present invention is
It is a mixture obtained by weighing and mixing 50% of the diatomaceous earth and 50% of the silica gel, respectively.

The test for confirming the pest control effect of the pest control material composed of such a mixture was carried out in the same manner as the above-mentioned demonstration test except that only the pest control material to be used was changed.

The observation results are as follows.

One hour after the introduction of termites into the petri dish in which the mixture as the pest control material was placed,
The 10 termites that were thrown in were still alive with the pest control material attached to the body, and all 3 animals had their antennae and legs flap, while the remaining 7 animals only had their antennae and legs slowly move. It was

Two hours after the introduction of the termites, 7 termites died, and the remaining 3 animals also only slightly moved their antennae and legs at each location.

After the lapse of 3 hours from the addition of the termites, all of the 10 termites that had been introduced died, and the confirmation test was completed.

By microscopic observation of the dead termites, it was confirmed that powdery pest control material had adhered to the skin of the termites including the stigmas on the body surface.

Therefore, also in this embodiment, the first and second pest control materials according to the diatomaceous earth pest control material are used.
It is thought that the termite died by the mechanism of.

The pest control effect of this pest control material is slightly enhanced as compared with the above-mentioned pest control material of diatomaceous earth alone, and the addition of silica gel maintained the diatomaceous earth in powder form and that of termite silica gel. It can be inferred that the dehydration phenomenon due to contact occurred together with the first and second mechanisms.

That is, since the powdery silica gel is added to the pest control material of this example as a substance having hygroscopicity as described above, the silica gel is preserved during storage of the pest control material or after spraying of the pest control material. Is mixed with diatomaceous earth, and it is possible to reduce powdery diatomaceous earth as an active ingredient from becoming clumped due to moisture, and the pest control effect by the first or second mechanism can be stably maintained.

In the above examples, a mixture of two kinds of substances, that is, powdery diatomaceous earth as an active ingredient and silica gel as a hygroscopic substance, is used, but the present invention is not limited to this. However, the pest control material may be configured by adding another substance to this, and the compounding ratio of each material in these cases may be appropriately selected. Further, in some cases, a drug having a weak drug effect such as boric acid may be supplementarily added.

[0087]

As described above, according to the invention of claim 1, in addition to the powdery diatomaceous earth, the pest control material is
Since a substance having a hygroscopic property is added, moisture such as moisture is absorbed by the substance having a hygroscopic property, and it is reduced that the powdery diatomaceous earth becomes lumpy, and the diatomaceous earth can maintain the powdery state. it can.

Therefore, the diatomaceous earth, which is powdery and has a particle size smaller than the distance between the hairs of the harmful insects to be exterminated, tends to adhere to the harmful insects without being hindered by the harmful insect hairs. Can be demonstrated.

[Brief description of drawings]

FIG. 1 is a schematic diagram for explaining a first mechanism relating to pest control with diatomaceous earth.

FIG. 2 is a schematic diagram for explaining a second mechanism relating to pest control with diatomaceous earth.

FIG. 3 is a particle size distribution diagram of diatomaceous earth.

FIG. 4 is a particle size distribution diagram of silica gel.

[Explanation of symbols]

P (body hair) spacing dimension 1 pest 3 body hair 41, 42, 43, 81, 82, 83 Pest control material (diatomaceous earth)

Claims (4)

[Claims] 1. A pest control material which is made of a solid matter and adheres to pests, wherein the solid matter contains powdery diatomaceous earth having a particle size smaller than the distance between the hairs of the pest to be exterminated. In addition to the above, a pest control material is characterized in that a substance having a hygroscopic property is added. 2. The pest control material according to claim 1, wherein the hygroscopic substance is added in powder form. 3. The pest control material according to claim 1 or 2, wherein silica gel is used as the hygroscopic substance. 4. The pest control material according to claim 1, wherein silicic acid anhydride is used as the hygroscopic substance.