JPH10218703A - Pest-controlling agent - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a pest-controlling agent excellent in preservation stability for a long time by including pregelatinized hydroxypropyl starch, a surfactant and water. SOLUTION: This pest controlling agent is obtained by formulating (A) 0.5-30wt.% pregelatinized hydroxypropyl starch preferably having 0.05-0.2 substitution degree (a proportion substituted by hydroxy propyl), (B) 0.5-10wt.% surfactant, (C) water and (D) optionally 0-30wt.% preparation adjuvant such as an antifreezing agent, an antiseptic agent, an organic solvent, a pigment and a flavor. The component A is obtained by reacting a natural starch obtained from a potato, a sweet potato, a wheat, a corn, a tapioca, a sago, a rice, etc., with propylene oxide under an alkaline condition at 40-50 deg.C for about 10hr, carrying out pregelatinization of the product by heat treatment, etc. The pest controlling agent is diluted so that the concentration of the component A may be about 100-10,000ppm, and sprayed on a pest (or a plant breeding the pest) by a power sprayer or a hanging type sprayer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a pesticide and a method for controlling pests.

[0002]

BACKGROUND ART Pest control agents containing pregelatinized starch as an active ingredient are known from JP-A-7-126105.

[0003]

However, the pesticidal agent containing pregelatinized starch as an active ingredient does not always have good long-term storage stability, and a phosphate is added to stabilize it. Ingenuity such as was needed.
(JP-A-8-319206)

[0004]

SUMMARY OF THE INVENTION The present invention is intended to improve storage stability by subjecting pregelatinized starch to hydroxypropylation, and comprises a preservative agent containing pregelatinized hydroxypropyl starch, a surfactant and water. It is intended to provide a biological control agent (hereinafter, referred to as "control agent of the present invention").

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The pregelatinized hydroxypropyl starch used in the present invention is obtained by subjecting starch to hydroxypropylation and pregelatinization. The hydroxypropylation treatment is generally performed by reacting starch with propylene oxide under alkaline conditions. The degree of substitution of hydroxypropyl starch (proportion of hydroxypropylation) is generally about 0.05 to 0.2, and especially about 0.08
It is preferably within the range of 0.15. Hydroxypropyl starch is obtained by reacting natural starch obtained from potato, sweet potato, wheat, corn, tapioca, sago, rice, etc. with propylene oxide under alkaline conditions at 40 to 50 ° C. for about 10 hours, and heat-treated. A pregelatinized treatment can be performed to lead to pregelatinized hydroxypropyl starch. α
Hydroxypropyl starch is usually present in the pesticidal composition of the present invention.
The content is 0.5 to 30% by weight, preferably about 1 to 15% by weight.

[0006] The surfactant used in the present invention is not particularly limited. Examples thereof include dialkyl sulfosuccinate surfactants such as Airroll CT-1 (manufactured by Toho Chemical Industry) and Neocol YSK (manufactured by Daiichi Kogyo Seiyaku). Examples include acetylene glycol-based surfactants such as Surfynol 104 (manufactured by Nissin Chemical), and silicone-based surfactants such as Silwet L-77 (manufactured by Witco) and KF-618 (manufactured by Shin-Etsu Chemical Co., Ltd.). Surfactants are usually present in the pesticidal composition of the present invention in an amount of from 0.5 to 0.5.
The content is 10% by weight, preferably about 1 to 5% by weight.

[0007] The control agent of the present invention contains, if necessary, an auxiliary agent for pharmaceutical preparations in addition to pregelatinized hydroxypropyl starch, a surfactant and water. The auxiliary agent for pharmaceutical preparations includes glycerin, ethylene glycol, propylene glycol, and the like. Examples include antifreezing agents such as polyethylene glycol and polypropylene glycol, preservatives, organic solvents, pigments, and fragrances.
Auxiliaries for preparations are usually contained in the control agent of the present invention in an amount of 0 to 30% by weight. When using a cryoprotectant, the cryoprotectant is
Usually, about 5 to 20% by weight is contained in the controlling agent of the present invention.

The controlling agent of the present invention is prepared by, for example, adding water to a container provided with a stirrer, and adding, while stirring, alpha-hydroxypropyl starch, a surfactant and, if necessary, an auxiliary agent for preparation, and mixing. It is manufactured by During mixing, if necessary, the mixture is heated to, for example, about 30 to 90 ° C. Also,
Hydroxypropyl starch is added and dispersed in water, heated and subjected to pregelatinization treatment, and a surfactant and the like are added and mixed to produce the pesticide of the present invention.

The pesticidal composition of the present invention is used for controlling pests by diluting with water and applying it to pests or plants where pests are generated. The degree of dilution varies depending on the type of pest to be controlled, the occurrence status, weather conditions, etc., but generally, the concentration of the pregelatinized hydroxypropyl starch in the diluent is about 100 to 10,000 ppm, preferably 500 to 5000 ppm.
The order of the degree is good.

The diluent for controlling agents of the present invention is sprayed on pests or plants on which pests are generated using a sprayer such as a power sprayer, a shoulder sprayer, a hand sprayer, etc., and citrus fruits, apples and the like. , Pears, spider mites that inflict fruit trees such as peaches, spider mites, spider mites, such as red mite, rust mite, Thripidae, cotton aphid,
Aphids such as peach aphid, Kanzawa spider mites, thrips pests infesting tea, aphids, spider mites, aphids, thrips pests infesting vegetables such as eggplant, cucumber, tomato, pepper, onion whitefly, tobacco whitefly, carnation ,rose,
Spider mites, aphids, thrips insects that infest flowers such as chrysanthemum, gypsum, gypsophila, poinsettia,
It is effective for controlling small insect pests such as whitefly and whitefly, and for controlling powdery mildew occurring in various crops.

The control agent of the present invention basically comprises the physical action of pregelatinized hydroxypropyl starch, that is, the pregelatinized hydroxypropyl starch adheres to pests and disables or significantly restricts the behavior of the pests. By doing so, it is thought to be due to the action of causing starvation, predation by other insects and animals, and respiratory obstruction. Therefore, the pesticidal composition of the present invention generally does not need to contain any pesticidal active ingredients such as insecticides, acaricides, fungicides, etc. The combined use of miticidally active ingredients such as mate, pyridaben, tetradiphone, phenothiocarb, propargite, dicofol, fenbutatin oxide is more effective in controlling mites that damage plants. In this case, the acaricide active ingredient is contained in the control agent of the present invention in an amount of about 0.1 to 5% by weight, and the concentration of the pregelatinized hydroxypropyl starch in the diluent is 1%.
The concentration of the acaricidal active ingredient in the diluent is about 100 to 10,000 ppm.
It may be used by diluting with water so as to be about 10 to 500 ppm.

[0012]

Next, the present invention will be described with reference to examples.
The present invention is not limited only to the following examples. Example 1 6 parts by weight of pregelatinized hydroxypropyl starch (degree of hydroxypropyl substitution: 0.1), 20 parts by weight of propylene glycol and 70.8 parts by weight of water were stirred and mixed, and further, an air roll CT-1 was added.
3 parts by weight of a dialkyl sulfosuccinate surfactant (manufactured by Toho Chemical Industry) and 0.2 parts by weight of Proxel GXL (a preservative manufactured by Zeneca) were added and stirred to obtain a pesticide of the present invention.

Example 2 6 parts by weight of pregelatinized hydroxypropyl starch (degree of hydroxypropyl substitution: 0.1), 10 parts by weight of propylene glycol and 78.8 parts by weight of water were mixed by stirring, and further, an air roll CT-1 was added.
5 parts by weight (a dialkyl sulfosuccinate surfactant manufactured by Toho Chemical Industry Co., Ltd.) and 0.2 parts by weight of Proxel GXL (a preservative manufactured by Zeneca Corporation) were added and stirred to obtain a pesticide of the present invention.

Example 3 6 parts by weight of pregelatinized hydroxypropyl starch (degree of hydroxypropyl substitution: 0.1), 10 parts by weight of propylene glycol and 80.8 parts by weight of water were mixed by stirring, and further mixed with Silwet L-77 (Wit).
3 parts by weight of a silicone surfactant manufactured by Co. Ltd. and 0.2 parts by weight of Proxel GXL (preservative manufactured by Zeneca) were added and stirred to obtain the pesticide of the present invention.

Example 4 Hydroxypropyl starch (hydroxypropyl substitution degree: 0.
1) 6 parts by weight, 10 parts by weight of propylene glycol and water 78.
8 parts by weight were mixed with stirring and heated at 80 ° C. for 1 hour to gelatinize the hydroxypropyl starch. Next, after cooling the mixture to room temperature, 5 parts by weight of KF-618 (silicone surfactant manufactured by Shin-Etsu Chemical Co., Ltd.) and 0.2 parts by weight of Proxel GXL (preservative manufactured by Zeneca) were added, and the mixture was thoroughly stirred to control the present invention. Agent was obtained.

Example 5 Hydroxypropyl starch (hydroxypropyl substitution degree: 0.
1) 6 parts by weight, 10 parts by weight of propylene glycol and 80.
8 parts by weight were mixed with stirring and heated at 80 ° C. for 1 hour to gelatinize the hydroxypropyl starch. Next, after cooling the mixture to room temperature, 3 parts by weight of Silwet L-77 (silicone surfactant manufactured by Witco) and 0.2 parts by weight of Proxel GXL (preservative manufactured by Zeneca) were added, and the mixture was stirred well to control the present invention. Agent was obtained.

Next, in the test examples described below, production examples of the control agent used as a comparative control are shown as reference examples. Reference Example A comparative control was performed in the same manner as in Example 1 except that 6 parts by weight of pregelatinized hydroxypropyl starch was replaced by 6 parts by weight of pregelatinized starch (Matsunoline M-22, manufactured by Matsutani Chemical Industry). Was obtained.

Example 6 The acaricide efficacy test against Citrus red mites was carried out according to the leaf disk method described on page 116 of "Agricultural Chemical Experiment Method 1 Insecticide Edition" (published by Soft Science Inc., 1981, edited by Fukami et al.). Changed and went. That is, water was poured into a petri dish having a diameter of 9 cm, a thin plate of styrofoam was floated, and a mandarin leaf cut to 3 cm × 3 cm was placed thereon. Next, thin paper whose central portion was cut out to the size of the mandarin orange leaf was moistened with water and placed on the mandarin orange leaf to prevent the escape of spider mites.
Approximately 20 adult female mites of the red mite spider mite were released on the tangerine leaves, and the diluent obtained by diluting the control agent of the present invention obtained in Examples 1 to 5 100 times with water was sprayed at about 20 mg / cm ² , and 24 hours after the treatment, The life and death of Citrus red mites was observed, and the mortality (%) was determined. Table 1 shows the results.

[0019]

[Table 1]

Example 7 A diluent obtained by diluting the control agent of the present invention obtained in Example 3 by 100 times with water was sprayed on a navel (16th grader) by a power sprayer in a sufficient amount. In addition, the same spraying was performed 7 days later. Table 2 shows the results of an investigation of the number of adults of the red mite, Parasitism spp., Which infests 50 leaves per tree over time (value converted into the number of mites per 100 leaves).

[0021]

[Table 2]

Example 8 100 ml of each of the control agents obtained in Examples 1 to 5 and Reference Example was packed in a polyethylene container, and the properties after storage at -5 ° C. for one week were observed. Each of the control agents obtained in Examples 1 to 5 was translucent, and although some separation was observed, it could be made uniform by gentle shaking. On the other hand, the control agent obtained in Reference Example was separated into two layers and gelled, and could not be easily redispersed.

[0023]

The pesticide of the present invention is a pesticide excellent in long-term storage stability.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Minoru Futami 4-2-1 Takashi Takarazuka-shi, Hyogo Prefecture Inside Agros Co., Ltd. (72) Inventor Kozo Tsuji 4-2-1 Takashi Takarazuka-shi Hyogo Prefecture Stock Association (72) Inventor Toshiro Otsubo 4-2-1 Takashi Takarazuka-shi, Hyogo Sumitomo Chemical Industry Co., Ltd.

Claims (2)

[Claims] 1. A pesticidal composition comprising alpha-hydroxypropyl starch, a surfactant and water. 2. A pest control method, which comprises applying a pesticidal diluent containing pregelatinized hydroxypropyl starch, a surfactant and water to pests or plants that produce pests.