JPS6072806A - Controlling agent against plant blight containing clathrate compound as active constituent - Google Patents

Abstract

PURPOSE:A controlling agent against plant blights, containing clathrate compound of 5-methyl-1,2,4-triazolo[3,4-b]benzothiazole (germicide) trapped in beta- cyclodextrin, and having improved residual effect of the above-mentioned germicide. CONSTITUTION:A controlling agent against plant blights containing a clathrate compound of 5-methyl-1,2,4-triazolo[3,4-b]benzothiazole trapped in beta-cyclodextrin as an active constituent in an amount of 0.1-99.9wt%, preferably 0.2-80wt%. The above-mentioned benzothiazole is a germicide, having low toxicity and penetration property, capable of exhibiting remarkable effect on blast of rice plants but causing volatilization of the active constituent on foliar application in field under high temperature and humidity conditions due to its high vapor pressure. Thus, it is difficult to keep the improved effect sufficiently and stably for a long period. The above-mentioned clathrate compound permits the prevention of the volatilization of the active constituent, and the residual effect can be remarkably improved.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides 5-methyl-1,2,4-triazolo(8,4
-b3benzothiazole (hereinafter abbreviated as the active ingredient of the present invention).

) The present invention relates to a plant disease control agent containing a β-cyclodextrin clathrate compound as an active ingredient.

The active ingredient of the present invention is a fungicide with low toxicity and permeability, and is known to be highly effective against rice blast. However, its vapor pressure is approximately 1.7X at 25℃
10 m#, and its vapor pressure is higher than that of other blast agents, so when the active ingredient of the present invention is used as a foliar spray in fields under high temperature and high humidity conditions, volatilization of the active ingredient occurs and its It has the disadvantage that it is difficult to sufficiently and stably maintain the excellent effect for a long period of time, that is, the residual effect is poor.

As a result of intensive research aimed at improving this drawback, the present inventors have discovered that by including the active ingredient of the present invention in β-cyclodextrin, its volatilization can be prevented and the residual effect can be dramatically improved. The present invention has been completed.

The β-cyclodextrin used in the present invention is a saccharide in which D-glucose obtained by treating starch or dextrin with an enzyme is bonded with α-1,4 in a heptad shape.

The clathrate compound used in the present invention can be obtained, for example, as follows. That is, the active ingredient lNN of the present invention is added as it is or dissolved in a small amount of acetone to a saturated aqueous solution of β-cyclodextrin in which 7.2 parts by weight of β-cyclodextrin is dissolved, and stirred for several hours to form a clathrate compound. can be obtained.

In addition, 7.2 parts by weight of β-cyclodextrin and about 1 part of water
A clathrate compound can be obtained by adding ixm parts of the active ingredient of the present invention to a mixture with 5 parts by weight and thoroughly stirring and kneading the mixture.

The clathrate compound obtained as described above can be further made into a powder by filtration or dehydration, washing, and drying, if necessary.

When the clathrate compound of the present invention is used as an active ingredient in a plant disease control agent, it may be used as is without adding other ingredients, but it is usually mixed with a solid carrier, liquid carrier, surfactant, or formulation adjuvant. It is then formulated into wettable powders, suspensions, granules, powders, etc.

These preparations contain the clathrate compound of the present invention as an active ingredient in a weight ratio of 0.1 to 99.9%, preferably 0.2 to 80%.
%contains.

Solid 4fi bodies include fine powders or granules such as kaolinite clay, attapulgite clay, bentonite, acid clay, pyrophyllite, talc, diatomaceous earth, urea, ammonium sulfate, and synthetic hydrous silicon oxide, and liquid carriers include water, etc. There is.

Surfactants used for emulsification, dispersion, wetting, etc. include alkyl sulfate ester salts, alkyl (aryl) sulfonates, dialkyl sulfosuccinates, polyoxyethylene alkylaryl ether phosphate ester salts, and formalin naphthalene sulfonate. Anionic surfactants such as condensates, polyoxyethylene alkyl ethers, polyoxyethylene polyoxypropylene block copolymers,
Examples include nonionic surfactants such as sorbitan fatty acid ester and polyoxyethylene sorbitan fatty acid ester.

Formulation auxiliaries include genin sulfonate, alginate, polyvinyl alcohol gum arabic, CMO (carboxymethyl cellulose), PAP (isopropyl acid phosphate), and the like.

These preparations can be used as they are or diluted with water, etc., and treated with foliage or soil. For soil treatment, the preparation can be applied to the soil surface (if necessary, mixed with the soil after application) or irrigated into the soil. Furthermore, by mixing and using it with other plant disease control agents, it can be expected that the control effect will be enhanced. In addition, insecticides, acaricides, nematicides, herbicides,
It can also be used in combination with plant growth regulators, fertilizers, soil conditioners, etc.

When the clathrate compound of the present invention is used as a plant disease control agent, the application amount is 0.000.0% per are as the amount of active ingredient.
05~toooop, preferably 0.1~20 (l), and when applying a wetting agent, suspending agent, etc. diluted with water, the application concentration is 0.005~1%, preferably 0.001 ~
The concentration is 0.2%, and granules, powders, etc. are applied as they are without any dilution.

The present invention will be described in more detail below based on Examples, but the present invention is not limited thereto. Note that parts are parts by weight.

Example 1 β-cyclodextrin (Celdex N, manufactured by Nippon Shokuhin Kako) 60 g, the active ingredient of the present invention 10 g, and water 150 g
- were sufficiently kneaded in a mortar for 2 hours (5). Next, this was air-dried and then pulverized using a pulverizer. Confirmation of the formation of clathrate compounds was confirmed by washing the obtained powder 8 times with acetone and then adding 1 dose of the active ingredient of the present invention.
This was done because the powder contained 1.5% and its powder X-ray spectrum was different from that of a simple mixture of the active ingredient of the present invention and β-cyclodextrin.

Example 2 Laikai machine (#J4 Ishikawa β-cyclodextrin) 7.2 parts by weight of IJ, about 10 parts by weight of water and 1 part by weight of the active ingredient of the present invention were stirred and kneaded for 2 hours. The obtained paste-like material was dried using a vacuum concentrator and then powdered using a pulverizer. Even after washing the obtained powder eight times with acetone, it was confirmed that it still contained 9.2% of the active ingredient.

Formulation Example 1 The clathrate compound produced in Example 1 was mixed with synthetic hydrated silicon oxide at a ratio of 10:1 (6), and then passed through a tabletop centrifugal mill (Nippon Seiki! 11) to form a fine powder. ), this fine powder 2.
9 parts, 0.3 parts of PAP (isopropyl acid phosphate) and 9 parts of kaolinite clay (Fubasami clay-A-800)
6.8 parts were mixed uniformly in a juice mixer to obtain a powder containing 0.8% of the active ingredient of the present invention.

Formulation Example 2 Same as Formulation Example 1, 4.8 parts of premix, PA P Q
, and 94.9 parts of kaolinite clay are uniformly mixed to obtain a powder containing 0.5% of the active ingredient of the present invention.

Formulation Example 8 Premix 9. Same as Formulation Example 1. s part, PAf'Q,
3 parts of kaolinite clay and 90.1 parts of kaolinite clay are uniformly mixed to obtain a powder containing 1% of the active ingredient of the present invention.

Formulation Example 4 Premix 76.6i, 8 parts of sodium lauryl sulfate, 2 parts of calcium lignosulfonate, and 18.4 g of diatomaceous earth were uniformly mixed in the same manner as in Formulation Example 1 to create a wettable powder containing 8% of the active ingredient of the present invention. get.

Formulation Example 5 Same as Formulation Example 1, 76.6 parts of premix, 4 parts of calcium ligninsulfonate, and 19 parts of kaolinite clay.
．． After 4 parts were mixed uniformly, 20 parts of water was added and kneaded.

After extruding this through a screen with a diameter of 0.7 mm, it is dried and sieved to a size of 16 to 82 meshes to obtain granules containing 8% of the active ingredient of the present invention.

Comparative Formulation Example 1 The active ingredient of the present invention and synthetic hydrated silicon oxide were mixed at a ratio of 1°:1 and pulverized using a tabletop centrifugal pulverizer (hereinafter abbreviated as pulverized bulk powder), 0.38 parts; 8 parts of P A P O and 99.87 parts of kaolinite clay are mixed uniformly in a juice mixer to obtain a powder containing 0.8% of the active ingredient of the present invention.

Comparative Formulation Example 2 Similar to Comparative Formulation Example 1, 0.55 parts of crushed bulk powder, PAPo,
8 parts of kaolinite clay and 99 and 15 parts of kaolinite clay were mixed uniformly to obtain a powder containing 0.5% of the active ingredient of the present invention.

Comparative Formulation Example 8 Same as Comparative Formulation Example 1, 1.1 parts of crushed bulk powder, P A P Q
, and 98.6 parts of kaolinite clay are uniformly mixed to obtain a powder containing 1% of the active ingredient of the present invention.

Comparative Formulation Example 4 Similarly to Comparative Formulation Example 1, 8.8 parts of crushed bulk powder, 2 parts of sodium lauryl sulfate, 8 parts of calcium lignosulfonate, and ±86.2 parts of diatom were mixed uniformly, and 8.8 parts of the active ingredient of the present invention was mixed. A hydrating agent containing % is obtained.

Comparative Formulation Example 5 Similar to Comparative Formulation Example 1, 8.8 parts of crushed bulk powder, 4 parts of calcium ligninsulfonate, and 87% of kaolinite clay were added.
．． (9) After adding 20 parts of water and kneading thoroughly, a diameter of 0.7
Granules containing 8% of the active ingredient of the present invention are obtained by extrusion through a millimeter screen, drying, and sieving.

Next, test examples will show that the clathrate compound of the present invention is useful as an active ingredient of a plant disease control agent.

The control efficacy is determined by visually observing the diseased state of the test plants at the time of the survey, that is, the degree of bacterial flora and lesions on leaves, stems, etc., and if no bacterial flora or lesions are observed, it is rated ``5'', about 10%. ``4'' if approved, ``8'' if approximately 80 copies are accepted, ``2'' if approximately 50 copies are accepted, rlJ if approximately 70 copies are accepted,
If there is no difference from the disease onset state when the compound is not tested, it is evaluated as "0" and evaluated on a 6-level scale from 0 to 5, and indicated as 0.1.2.8.4.5.

Test Example 1 Rice blast control test (residual effect) A plastic pot was filled with sandy loam, rice (Kinki No. 88) was sown, and mushrooms were grown in a greenhouse for 21 days (lO). The powders obtained from Formulation Examples 1 to 8 and Comparative Formulation Examples 1 to 8 were applied to the seedlings at the 2.5th leaf stage when the leaves had developed using a midget duster so that the powders were sufficiently attached to the leaf surface.
11f/10a was sprayed on foliage. After spraying, the rice blast fungus (Pyricularia o.
ryzae) was sprayed and inoculated. After inoculation, the plants were grown for 4 days at 28°C under humid conditions, and their pesticidal efficacy was investigated.

The results are shown in Table 1.

Table 1 Test Example 2 Rice blast control test (residual effect) A plastic pot was filled with sandy loam, and rice (Kinki No. 38) was sown and grown in a greenhouse for 21 days. The second stage developed by Konoha
．． The hydrating powders obtained in Formulation Example 4 and Comparative Formulation Example 4 were diluted with water to a predetermined concentration and sprayed on seedlings at the 5-leaf stage so as to sufficiently adhere to the leaf surface. After spraying, the rice blast fungus (Pyricularia) was grown in a greenhouse for 14 days.
oryzae) was sprayed and inoculated. After inoculation, the plants were grown for 4 days at 28°C under humid conditions, and their pesticidal efficacy was investigated. The results are shown in Table 2.

Table 2 Test Example 8 Rice blast control test (osmotic transfer effect) A 115,000 a Wagner pot was filled with sandy loam soil, and young rice seedlings (Kinki No. 88, 2-leaf stage) were transplanted and grown in a greenhouse for 14 days. The granules obtained in Formulation Example 5 and Comparative Formulation Example 5 were uniformly sprinkled on seedlings at the 4.5 leaf stage in water. After treatment, the plants were grown in a greenhouse for 21 days, and then sprayed and inoculated with a spore suspension of the rice blast fungus. After inoculation, the plants were grown for 4 days at 28°C under humid conditions, and their pesticidal efficacy was investigated.

The results are shown in Table 8.

Table 8 (1B completed)

Claims (1)

[Scope of Claims] A plant disease control agent characterized by containing a β-cyclodextrin clathrate of 5-methyl-1,2,4-triazolo[8°4-b)benzothiazole as an active ingredient.