Pest control agent

Abstract

To provide a pest control agent that has little influence on plants and has prompt efficiency.SOLUTION: A pest control agent comprises aqueous slurry comprising fine particles of hydrated lime, a surfactant and water, the fine particles of hydrated lime having an average particle size of (D50) of 0.1-1.0 μm, and the content of the fine particles of hydrated lime being 8-50 mass%.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a pest control agent for controlling pests such as slugs.

Background Art

[0002] In recent years, pesticide-free cultivated vegetables that do not use pesticides have become increasingly popular. However, in farms that practice pesticide-free cultivation, damage caused by pests such as slugs and snails has become a problem. Under such circumstances, a formaldehyde preparation is used as an attractant bait for pests such as slugs and snails (see Patent Document 1). However, this formaldehyde preparation cannot directly kill pests upon contact, lacks immediate effectiveness, and does not provide a sufficiently satisfactory effect.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] An object of the present invention is to provide a pest control agent that has little impact on plants and has immediate effectiveness.

Means for Solving the Problems

[0005] In order to solve the above problems, the inventor focused on slaked lime (calcium hydroxide), which does not fall under pesticides and has a bactericidal effect. However, since slaked lime is a strong alkali, there is concern about its impact on plants when used in powder form, although it is not as harmful as pesticides.

[0006] Under such circumstances, as a result of further intensive research, the inventors of the present invention have found that by using an aqueous slurry containing micronized slaked lime, the carbonation (inactivation) of slaked lime proceeds immediately after application, damage to plants can be suppressed, and by further incorporating a surfactant into the aqueous slurry, the wettability is improved, so that it spreads thinly and widely on the leaves of plants, etc., damage to plants can be suppressed, and the wettability and penetrability to pests are enhanced, and it has been found that even a small amount of slaked lime can exhibit sufficient killing power, thus completing the present invention.

[0007] That is, the present invention is as follows. [1] An aqueous slurry containing slaked lime fine particles, a surfactant, and water, wherein the average particle diameter (D50) of the slaked lime fine particles is 0.1 to 1.0 μm, and the content ratio of the slaked lime fine particles is 8 to 50% by mass, a pest control agent.

[0008] [2] The pest control agent according to [1] above, wherein the content ratio of the surfactant is 2 to 20% by mass. [3] The pest control agent according to [1] or [2] above, wherein the contact angle with respect to a polypropylene sheet is 5 to 50°. [4] The pest control agent according to any one of [1] to [3] above, which is in a spray form. [5] The pest control agent according to any one of [1] to [4] above, wherein the pest to be controlled is a soft-bodied pest selected from yam beetles, slugs, snails, caterpillars, sweet potato weevils, and green caterpillars. [Effects of the Invention]

[0009] The pest control agent of the present invention has little impact on plants and is excellent in immediate effectiveness. [Modes for Carrying Out the Invention]

[0010] The pest control agent of the present invention is an aqueous slurry containing slaked lime fine particles, a surfactant, and water, wherein the average particle diameter (D50) of the slaked lime fine particles is 0.1 to 1.0 μm, and the content ratio of the slaked lime fine particles is 8 to 50% by mass.

[0011] The pest control agent of the present invention is directly applied to pests parasitizing on plants and the like to kill the pests. Since the pest control agent of the present invention is an aqueous slurry containing atomized slaked lime, carbonation (inactivation) of the slaked lime proceeds immediately after application, and damage to plants such as alkali burn can be suppressed. In addition, since it contains a surfactant, it spreads thinly and widely on the leaves of plants and the like due to improved wettability, damage to plants can be suppressed, and the wettability and permeability to pests are enhanced, and sufficient killing power can be exhibited even with a small amount of slaked lime.

[0012] The pests targeted by the pest control agent of the present invention are not particularly limited as long as they are pests that die by the action of the pest control agent of the present invention. For example, in addition to soft-bodied pests such as yam slugs, slugs, snails, caterpillars, sweet potato bugs, and green caterpillars, ants, pill bugs, etc. can be mentioned. Among these, soft-bodied pests such as yam slugs, slugs, snails, caterpillars, sweet potato bugs, and green caterpillars are preferred.

[0013] Caterpillars, sweet potato bugs, and green caterpillars refer to the larvae of the order Lepidoptera (butterflies). For example, the larvae of butterflies of the families Papilionidae, Pieridae, Lycaenidae, Nymphalidae, and Pieridae, and the larvae of moths of the families Limacodidae, Psychidae, Dalceridae, Lymantriidae, Lasiocampidae, Pyralidae, Noctuidae, Notodontidae, Nymphalidae, Saturniidae, Lasiocampidae, Lymantriidae, Erebidae, Sphingidae, Cossidae, Euteliidae, Crambidae, and Geometridae can be mentioned. The distinction between caterpillars, sweet potato bugs, and green caterpillars is not strict, but those covered with long hairs can be classified as caterpillars, and among those not covered with long hairs, those other than green can be classified as sweet potato bugs, and those that are green can be classified as green caterpillars.

[0014] In the pest control agent of the present invention, the average particle diameter (D50) of the slaked lime fine particles is 0.1 to 1.0 μm, preferably 0.1 to 0.8 μm, and more preferably 0.1 to 0.5 μm. By using fine particles in this range, the inactivation of slaked lime proceeds immediately, and damage to plants can be suppressed. Further, the pest control agent of the present invention preferably contains as little slaked lime fine particles of 1.2 μm or more as possible. For example, the slaked lime fine particles of 1.2 μm or more are preferably 5% by volume or less, more preferably 3% by volume or less, and even more preferably 1% by volume or less.

[0015] The average particle diameter (D50) means the particle diameter at the point where it becomes 50% in the cumulative volume distribution curve with the total volume of the particle size distribution determined on a volume basis being 100%, that is, the volume-based cumulative 50% diameter. The particle size distribution can be determined by a laser diffraction / scattering type particle size distribution measuring device (for example, LA-960 manufactured by Horiba, Ltd.).

[0016] The content ratio of the slaked lime fine particles in the pest control agent of the present invention is 8 to 50% by mass, preferably 10 to 40% by mass, and more preferably 10 to 30% by mass. By containing slaked lime fine particles in this amount range, pests can be surely killed.

[0017] The content ratio of the surfactant in the pest control agent of the present invention is preferably 2 to 20% by mass, more preferably 3 to 15% by mass, and even more preferably 3 to 10% by mass. By containing a surfactant in this amount range, it can spread thinly on leaves and the like to suppress damage to plants, and at the same time, the wettability and permeability to pests are enhanced, improving the killing effect.

[0018] As the surfactant, any surfactant such as an ionic surfactant, an amphoteric surfactant, or a nonionic surfactant may be used. Examples of the ionic surfactant include sodium dodecylbenzenesulfonate, sodium lauryl sulfate, and sodium polyoxyethylene alkyl ether sulfate. Examples of the amphoteric surfactant include lauryl betaine and lauryldimethylamine oxide. Examples of the nonionic surfactant include polyoxyethylene alkyl ether, polyethylene glycol fatty acid ester, acetylene glycol, and acetylene alcohol. In addition, hydroxypropyl methylcellulose, hydroxyethyl cellulose, etc. can also be used.

[0019] The contact angle of the pest control agent of the present invention with respect to the polypropylene sheet is preferably 5 to 50°, more preferably 40° or less, still more preferably 35° or less, and even more preferably 30° or less. Thereby, sufficient wettability with respect to plants and pests can be ensured.

[0020] Note that the contact angle in the present invention refers to the contact angle of the liquid droplet 20 seconds after dropping the liquid droplet onto the polypropylene sheet. For measurement, for example, a dynamic surface tensiometer PCA-1 (manufactured by Kyowa Interface Science Co., Ltd.) can be used.

[0021] In the pest control agent of the present invention, in addition to the above components, other components may be contained. For example, it is preferable to contain alcohol. By containing alcohol, the permeability to pests can be enhanced. Examples of the alcohol include methanol, ethanol, n-propyl alcohol, and isopropyl alcohol. From the viewpoints of safety and the like, ethanol is preferable.

[0022] The content ratio of alcohol is preferably 2 to 20% by mass, more preferably 3 to 15% by mass, and still more preferably 3 to 10% by mass. By containing alcohol in this range, the pest control agent can be efficiently penetrated into pests, and the killing property can be improved.

[0023] The pest control agent of the present invention can be used in the form of a spray type (atomization type), a dropping type, etc., and from the viewpoints of ease of use and suppression of excessive application, the spray type is preferable. Since the pest control agent of the present invention contains fine slaked lime particles and a surfactant and can stably maintain a slurry state, the spray type can be suitably used.

[0024] The pest control agent of the present invention can be produced by mixing slaked lime fine particles, a surfactant, and water. For example, it can be produced by producing a slaked lime fine particle dispersion liquid by the production method described in Japanese Patent No. 4606238 and adding an appropriate amount of a surfactant and water to such a slaked lime fine particle dispersion liquid.

Examples

[0025] Examples and comparative examples are shown below, but the technical scope of the present invention is not limited thereto.

[0026] A pest control agent was produced using the following raw materials. As the slaked lime fine particles, fine particle slaked lime slurry “CalSetter” (manufactured by Tokuyama Corporation) was used. The average particle diameter (D50) was 0.2 to 0.4 μm, and it hardly contained particles of 1.0 μm or more. In Comparative Example 3, calcium carbonate fine particles were used instead of the slaked lime fine particles. As the surfactant, Orfin E1010 (manufactured by Nissin Chemical Industry Co., Ltd.) was used. As the alcohol, ethanol was used.

[0027] The specific blending ratios are as shown in Table 1. In addition, the measurement results of the contact angles of each pest control agent are also shown. The contact angle was measured using a dynamic surface tensiometer PCA-1 (manufactured by Kyowa Interface Science Co., Ltd.), and the contact angle of the liquid droplet after 20 seconds was read by dropping the liquid droplet onto a polypropylene sheet.

[0028]

Table 1

[0029] The pest control agents of Examples 1 to 6 and Comparative Examples 1 to 3 were applied (dropped) to slugs, caterpillar larvae (sweet potato hornworms), and ermine moth larvae (cabbage loopers). After dropping, the death of the pests was confirmed when the pests stopped moving for 10 minutes. The results are shown in Table 2.

[0030]

Table 2

[0031] As shown in Table 2, by applying a small amount of the pest control agent of the present invention, the pests could be killed.

[0032] Next, the pest control agents of Examples 1 to 6 and the slaked lime slurry or powdered slaked lime of Comparative Examples 4 to 7 having the formulations shown in Table 3 below were applied (sprayed) to the leaves of tomatoes, potatoes, and citrus fruits. Five days after spraying, the slaked lime adhering to the leaves was removed, and the ratio of the number of leaves with alkali burn on the leaves (the number of leaves with alkali burn to the number of sprayed leaves) was confirmed.

[0033]

Table 3

[0034] The results are shown in Table 4. The evaluation of the alkali burn of the leaves was carried out according to the following criteria. ○: There are no leaves with alkali burn, or less than 5% △: The number of leaves with alkali burn is 5% or more and less than 25% ×: The number of leaves with alkali burn is 25% or more

[0035]

Table 4

[0036] As shown in Table 4, alkali burning of leaves occurred in the slaked lime slurry or powdered slaked lime of Comparative Examples 4 to 7, but in the pest control agents of Examples 1 to 6 of the present invention, almost no alkali burning of leaves occurred and there was almost no impact on plants.

Industrial Applicability

[0037] Since the pest control agent of the present invention can be suitably used for controlling pests such as slugs and caterpillars, it is industrially useful.

Claims

Claim 1 An aqueous slurry containing slaked lime fine particles, a surfactant, and water, wherein the average particle diameter (D50) of the slaked lime fine particles is 0.1 to 1.0 μm, and the content ratio of the slaked lime fine particles is 8 to 50% by mass, A pest control agent for controlling soft pests selected from yam beetles, slugs, snails, caterpillars, mealworms, and green caterpillars. Claim 2 The pest control agent according to claim 1, wherein the content ratio of the surfactant is 2 to 20% by mass. Claim 3 The pest control agent according to claim 1 or 2, wherein the contact angle with respect to a polypropylene sheet is 5 to 50°. Claim 4 The pest control agent according to any one of claims 1 to 3, which is of a spray type.

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