JPH06219909A - Improved agricultural fungicide composition - Google Patents

Abstract

(57) [Summary] [Objective] To obtain an effective agricultural fungicide composition with a low dosage. A composition for agricultural fungicides, comprising a cyclodextrin inclusion compound of 3'-isopropoxy-2-methylbenzanilide. [Effect] When Mepronil was applied to the surface of water to control rice blight, the effective ingredient was 400 per 10 ares.
Even if g was dropped, a practically effective effect was not obtained and it was impossible to use it as a water surface application agent. The agricultural fungicidal composition of the present invention, 100 g of which is one fourth of the active ingredient, can provide sufficient effects, and mepronil can be used as a water surface application agent. In the same way, it is possible to reduce the dose in foliar treatment, and it is 1/4 to 1 / the conventional one against rice rust disease, rust disease of various crops caused by basidiomycetes, white silk disease, rhizoctonia disease, etc. 1
A similar effect is obtained with a dose of 0.

Description

Detailed Description of the Invention

[0002]

This invention relates to 3'-isopropoxy-
2-methylbenzanilide (hereinafter referred to as mepronil)
And a cyclodextrin clathrate compound as an active ingredient.

[0003]

BACKGROUND OF THE INVENTION Mepronil is a fungicide effective against plant diseases derived from various basidiomycetes represented by Rhizoctonia, and is used for rice blight, turf rhizoctonia large patches, seedling wilting, radish root rot, Widely used as a foliar spray for leaf rot and the like. Regarding the inclusion of pesticide active ingredients with cyclodextrin, the extension of the residual effect (JP-A-49-
71135, 49-134844, 55-14.
No. 9202, No. 55-149203, No. 59-334.
No. 01), and improved adhesion and stickiness (Japanese Patent Laid-Open No. 58-134).
004) and improvement of unpleasant irritating odor (JP-A-51-9513).
5), reduction of fish poison (JP-A-55-81806) and the like are known.

[0004]

In recent years, the problem of environmental pollution caused by pesticides has been widely dealt with, and there is a need for efficient use by reducing the number of times and the amount of spraying of chemicals as much as possible. However, in order to fully exert the physiological activity of the pesticide, there is an appropriate amount of application depending on the pesticide compound used, and if applied less than that, no sufficient effect will be obtained and damage by pests and weeds will not be obtained. Affect the harvest by. Therefore, it has been earnestly desired to develop a drug that reduces the amount of the same drug to be sprayed and gives a sufficient effect.

[0005]

Means for Solving the Problems As a result of intensive studies for solving the above problems, the present inventors have found that an agricultural fungicide composition of the present invention containing a cyclodextrin inclusion compound of mepronil as an active ingredient is unique. The present invention has been completed by finding that the control effect is effectively improved, and that it has an effective bactericidal effect with a low dose. That is, the present invention provides a fungicide composition for agriculture, which comprises a cyclodextrin inclusion compound of mepronil as an active ingredient. The cyclodextrin used in the present invention is a known substance in which 6 to 9 glucoses are cyclically constituted by α-1,4 bonds.
It is classified as-, β-, γ-, δ-cyclodextrin. Other examples include methylcyclodextrin, dimethylcyclodextrin, ethylcyclodextrin, hydroxypropylcyclodextrin, diethylaminoethylcyclodextrin, and maltosylcyclodextrin whose glucose side chains are chemically modified. In the present invention, it is preferable to use β-cyclodextrin. In preparing an inclusion compound, as a general method, mepronil and cyclodextrin are dissolved in water or a mixed solvent of water and an organic solvent to obtain both as coprecipitates, or water is added and kneaded in a mortar or ball mill. It is obtained by drying the dried product. At this time, it is possible to simultaneously mix and knead auxiliary agents and extenders usually used for agricultural chemical formulations to prepare powders, wettable powders, granules and the like. In the preparation of the inclusion compound, the mixture of mepronil and cyclodextrin is preferably placed in a container which can be sealed, and 1
A good clathrate compound can be obtained by heating at 80 to 220 ° C. for about 1 to 3 hours, or by pulverizing with a wet fine pulverizing apparatus represented by a sand grinder or a dynomill, and drying.

The composition of the present invention requires 2 mol or more of cyclodextrin per 1 mol of mepronil, and usually contains 2 mol of cyclodextrin per 1 mol of mepronil, but 2 mol of cyclodextrin per 1 mol of mepronil. In the case of the following blending amounts, the ratio of clathrate mepronil decreases, but if a sufficient bactericidal effect is obtained,
The compounding amount may be less than or equal to mol. The improved agrochemical formulation composition of the present invention contains an inclusion compound of mepronil and cyclodextrin, and further, it is possible to add an auxiliary agent or a bulking agent used in a usual agrochemical formulation, if necessary. For example, other pesticides and fungicides can be added to prepare a mixture. Examples of the auxiliary agent include a surfactant, a physical property improver, a decomposition inhibitor, a binder, and the like.As the surfactant, a polyoxyethylene alkyl ether, a nonionic surfactant such as polyoxyethylene alkylallyl ether, and the like,
These include sulfates, phosphates and anionic surfactants such as alkylbenzene sulfonates and alkyl sulfates. Examples of the physical property improver or decomposition inhibitor include isopropyl acid phosphate, higher fatty acid and its metal salt, higher alcohol, soybean oil and the like. Examples of the binder include polyvinyl alcohol, sodium salt of carboxymethyl cellulose, polyethylene glycol and the like. As a bulking agent,
Examples thereof include natural mineral substances such as clay, talc, bentonite and diatomaceous earth, inorganic salts such as calcium carbonate, calcium sulfate and barium sulfate, sugars such as sucrose, glucose and lactose, and white carbon.

[0007]

EXAMPLES Next, examples and test examples of the present invention will be described, but the present invention is not limited to these examples. All parts in each example are parts by weight.

Example 1 To 25 parts of mepronil and 200 parts of β-cyclodextrin, 1000 parts of water was added, and this was mixed and pulverized with Dynomill (manufactured by Shinmaru Enterprise Co., Ltd.) for 30 minutes and then dried at 80 ° C. for 2 hours. Then, mepronil inclusion powder was obtained. To this, 25 parts of polyvinyl alcohol, 300 parts of bentonite, and 450 parts of clay were added, and after uniformly mixing, an appropriate amount of water was added and granulated with a granulator equipped with a screen having a diameter of 1.0 mm. After drying, the granules were sized to obtain granules containing 2.5% of mepronil.

Example 2 The β-cyclodextrin of Example 1 was replaced with α-cyclodextrin to obtain granules containing 2.5% mepronil.

Example 3 The β-cyclodextrin of Example 1 was replaced with γ-cyclodextrin to obtain granules containing 2.5% mepronil.

Example 4 25 parts of mepronil, 200 parts of β-cyclodextrin,
30 parts of starch, 250 parts of bentonite, and 500 parts of calcium carbonate were uniformly mixed, 400 parts of water was added, and the mixture was kneaded with a kneader (KDH-10 type manufactured by Fuji Sangyo Co., Ltd.) for 10 minutes. After granulating with a granulator equipped with a screen, drying and sizing, a granule containing 2.5% of mepronil was obtained.

Example 5 The β-cyclodextrin of Example 4 was converted to maltosyl-α-
Replaced with cyclodextrin, Mepronil 2.5%
A granule containing was obtained.

Example 6 The β-cyclodextrin of Example 4 was replaced with dimethyl-β-cyclodextrin to obtain granules containing 2.5% of mepronil.

Example 7 1000 parts of mepronil and β-cyclodextrin 4
After 200 parts were dissolved by heating in a mixed solvent of ethanol / water (1/10, volume ratio) with heating, the crystals were separated by cooling by cooling. The content of mepronil in this crystal was quantified under the gas chromatographic conditions shown below, and as a result, an inclusion crystal containing 19.0% of mepronil was obtained. 790 parts of this clathrate crystal, 30 parts of polyoxyethylene nonylphenyl ether, 30 parts of polyoxyethylene styryl phenyl ether ammonium sulfate, and white carbon 10
0 part and 50 parts of clay were uniformly mixed and pulverized to obtain a wettable powder containing 15% of mepronil. Gas chromatograph conditions: Model Shimadzu GC-7A column Silicon SE-30 3% (Uniport
HP) φ3mm × 1m Detector FID (hydrogen flame ionization detector)

Example 8 790 parts of the clathrate crystals obtained in Example 7, 30 parts of polyoxyethylene octyl phenyl ether, 30 parts of sodium lauryl sulfate, 100 parts of white carbon and 50 parts of ammonium sulfate were uniformly mixed and pulverized to obtain 15 mepronil. A wettable powder containing 100% was obtained.

Example 9 Mepronil 50 parts and β-cyclodextrin 500
Parts, 50 parts of sodium lignin sulfonate, 50 parts of sodium polyoxyethylene lauryl sulfate, 100 parts of white carbon, and 250 parts of clay are added with 2000 parts of water and uniformly mixed and pulverized by a dyno mill to form a paste. This paste was dried and granulated by a spray drying method to obtain a granular wettable powder containing 5% mepronil.

Example 10 Mepronil 10 parts, and hydroxypropyl-β-cyclodextrin 140 parts, white carbon 120
Part and 730 parts of clay at 200 ° C in a closed container.
And heated for 2 hours to obtain a mepronil inclusion powder. The powder was uniformly pulverized to obtain a dust containing 1% of mepronil.

Example 11 Hydroxypropyl-β-cyclodextrin of Example 10 was replaced with β-cyclodextrin to obtain a dust containing 1% of mepronil.

Comparative Example 1 25 parts of mepronil and 25 parts of polyvinyl alcohol,
300 parts of bentonite and 650 parts of clay were added and uniformly mixed, then an appropriate amount of water was added and granulated with a granulator equipped with a screen having a diameter of 1.0 mm, and the granulated product was dried and then sized. A granule containing 2.5% of mepronil was obtained.

Comparative Example 2 Mepronil 25 parts, starch 25 parts, bentonite 25
0 parts and 700 parts of calcium carbonate are evenly mixed,
Add 400 parts of water and kneader (KDH-1 manufactured by Fuji Sangyo)
(Type 0) was kneaded for 10 minutes, granulated with a granulator equipped with a screen having a diameter of 1.0 mm, dried, and sized to obtain granules containing 2.5% of mepronil.

Comparative Example 3 150 parts of mepronil, 30 parts of polyoxyethylene nonylphenyl ether, 20 parts of polyoxyethylene styryl phenyl ether ammonium sulfate, 100 parts of white carbon and 700 parts of clay were uniformly mixed and pulverized to contain 15% of mepronil. A wettable powder was obtained.

Comparative Example 4 150 parts of mepronil, 30 parts of polyoxyethylene octyl phenyl ether, 20 parts of sodium lauryl sulfate,
White carbon 200 parts, β-cyclodextrin 6
00 parts were uniformly mixed and pulverized to obtain a wettable powder containing 15% of mepronil.

Comparative Example 5 150 parts of mepronil and 150 parts of polyoxyethylene nonylphenyl ether ammonium phosphate, 50 parts of polyoxyethylene nonyl phenyl ether, 250 parts of triethyl phosphate and 400 parts of tributyl phosphate were uniformly dissolved to give mepronil. An emulsion containing 15% was obtained.

Comparative Example 6 150 parts of mepronil, 100 parts of polyoxyethylene lauryl ether, 100 parts of polyoxyethylene styryl phenyl ether ammonium sulfate, 150 parts of isophorone.
Parts and 500 parts of acetonitrile were uniformly dissolved to obtain an emulsion containing 15% of mepronil.

Comparative Example 7 10 parts of mepronil, 200 parts of white carbon, and 790 parts of clay were uniformly mixed and pulverized to obtain a dusting agent containing 1% of mepronil.

Comparative Example 8 Mepronil 10 parts and β-cyclodextrin 140
Parts, white carbon 200 parts, and clay 650 parts were uniformly mixed and pulverized to obtain a dust containing 1% of mepronil.

Test Example 1 Rice crest disease control test (water surface application) Using the granules of Examples 1 to 6 and Comparative Examples 1 and 2, a rice crest disease control test by water surface application was performed according to the following test method. It was (Test method) Test scale: Field test, 1 area 10 m ² , 3 repetitions Test plant: Paddy rice, cultivar; Japanese clams Inoculation: 45 days before heading of rice, rice wilt fungus was cultured in rice husk bran medium for 2 weeks ( Thanatephorus cucumeris) was diluted 5 times with rice husk, and 30 l / 10a equivalent amount was evenly distributed in the field. Dispersal: 2k per 10a for each test agent 21 days before heading
An equivalent amount of g and 4 kg was uniformly processed on the water surface by hand. Investigation: After 35 days of heading, 20 strains were cut per ward and investigated according to the following criteria, and the disease severity was calculated by the following formula to determine the control value. The severity of disease in untreated plots is 43.6%.
Met. The results are shown in Table 1.

N: Number of stalks investigated n ⁴ : Stem that developed disease to leaf sheath, n ³ : Stem that developed to second leaf sheath n ² : Stem that developed to third leaf sheath n ¹ : Stem that developed to fourth leaf sheath

[0029]

[Equation 1]

[0030]

[Equation 2]

[0031]

[Table 1]

Test Example 2 Cucumber seedling blight control test (irrigation treatment) Using the agents of Examples 7 and 9 and Comparative Examples 3 and 5, the cucumber seedling blight control test was carried out according to the following test method. (Test method) Cucumber seedling blight (Rhizoctonia solani), which had been cultivated in a soil bran medium for 21 days, was diluted 20 times with sterilized soil and filled in 9 cm × 9 c pots. After sowing 10 cucumber seeds (variety; Sagamihanjiro) per pot and covering with soil,
A chemical solution diluted to a predetermined concentration with water was irrigated in an amount equivalent to 3 l / m ² (3 pots in 1 ward), placed in a greenhouse, and 10 days after the chemical treatment, it was investigated according to the following criteria, and the germination rate and the healthy seedling rate were calculated according to the following formulas. , Killing rate and morbidity were calculated. Index Non-germination, wilting = 3 Growth failure = 1 Healthy seedling = 0 The results are shown in Table 2.

[0033]

[Equation 3]

[0034]

[Equation 4]

[0035]

[Equation 5]

[0036]

[Equation 6]

[0037]

[Table 2]

Test Example 3 Rice crest disease control test (stem and leaf spraying) Using the agents of Examples 7 to 9 and Comparative Examples 3 to 6, a rice crest disease control test was conducted according to the following test method. (Test method) 15 seeds of paddy rice (variety: Kinnanfu) were sown in a biscuit pot with a diameter of 9 cm, and grown in a greenhouse for 4 to 5 weeks. The rice seedlings on which the fifth leaf had spread were sprayed with 10 ml of a drug solution diluted with water to a predetermined concentration (3 pots in 1 ward). After air-drying, rice husk fungus (Thanatep
horus cucumeris) was inoculated into the strain source and immediately put in a humid chamber at 28 ° C. After 7 days, the length of the lesions formed on the rice leaf sheath was measured, and the control value was calculated by the following formula. The untreated lesion length was 12.5 cm. The results are shown in Table 3.

[0039]

[Equation 7]

[0040]

[Table 3]

Test Example 4 Turf Large Patch Control Test Using the agents of Examples 1-9 and Comparative Examples 1-6, a turf rhizoctonia large patch control test was conducted under the following test conditions. (Test method) Test scale: Field test, 1 area 30 m ² Specimen: Korishiba Spray: Wettable powder, granules Wettable powder and emulsion are each diluted to the specified concentration with water, and 1 l / m ² equivalent is small. Sprayed with a power sprayer. A predetermined amount of granules was sprayed with a small granulator. In addition, for each dosage form, spraying is done before the first large patch and the second.
Two times after the first week, the treatment amount is 1 for the active ingredient.
0.5 g was sprayed per 0 ares. Investigation: The lesion area was measured 3 weeks after the final application. The results are shown in Table 4.

[0042]

[Table 4]

Test Example 5 Rice crest disease control test (stem and leaf spraying) Using the agents of Examples 10 and 11 and Comparative Examples 7 and 8 and according to the following test method, a rice crest and leaf disease control test was carried out. . (Test method) 15 seeds of paddy rice (variety: Kinnanfu) were sown in a biscuit pot with a diameter of 9 cm, and grown in a greenhouse for 4 to 5 weeks. A predetermined amount of each drug was sprayed onto the rice seedlings having the fifth leaves developed (1 pot, 3 pots). Then, the rice leaf blight fungus (Thanatephorus cucumeri) cultured in rice husk bran medium was used.
s) was inoculated into the strain source and immediately placed in a humid chamber at 28 ° C. 7
After a day, the length of the lesion formed on the rice leaf sheath was measured, and the control value was calculated in the same manner as in Test Example 3. The lesion size in the untreated section was 11.6 cm. The results are shown in Table 5.

[0044]

[Table 5]

[0045]

EFFECTS OF THE INVENTION Mepronil cannot be used as a water surface application agent, even if it is thrown at 500 g per 10 ares as an active ingredient, the effect of controlling water crust disease by water surface application is not recognized. The agricultural fungicidal composition of the present invention can exert a sufficient effect with 50 to 100 g of active ingredient per 10 ares. By using mepronil as an inclusion compound with cyclodextrin, mepronil is applied to the water surface. Can be used as. Similarly, it is possible to reduce the dose in foliar treatment as well, and rust of various crops due to Basidiomycetes including rice blight, white silkworm, rhizoctonia, such as pear scab, kaku rust, wheat, Rust disease of turf, root rot, leaf rot caused by Rhizoctonia,
Similar effects can be obtained with a dose of about 1/4 to 1/10 of the conventional amount against vegetable seedling blight, wheat caused by T. flavum, snow rot of turf, etc.

Claims (1)

[Claims] 1. A fungicide composition for agriculture, which comprises a cyclodextrin inclusion compound of 3'-isopropoxy-2-methylbenzanilide. [0001]