JPS6121444B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a novel sterilizing composition for agricultural and horticultural use, and more specifically, to a sterilizing composition for agricultural and horticultural use that has preventive and therapeutic effects against rice blast, Mongol blight, and the like. The three major diseases of rice are rice blast, mongare disease,
White leaf blight is known, and blast disease in particular causes a large decrease in yield, so the importance of its control is recognized, and currently organophosphorus agents, organic chlorine agents, antibiotics, etc. are being used to control blast disease. It is used. However, the effects of all drugs are either preventive or therapeutic, and therefore it is necessary to use them according to their characteristics.
~4 applications are required. Furthermore, in recent years, labor saving has progressed through the introduction of various types of machinery in rice cultivation, and the method of growing seedlings using seedlings has rapidly become popular. The temperature and humidity of this seedling nursery are extremely favorable for the growth and infection of the blast fungus.
For this reason, especially in regions where medium-sized seedlings are transplanted 25 to 30 days after sowing, seedling blast disease occurs during the box-raised period, which not only makes it impossible to use the seedlings, but also causes leaf blast after Honda transplanting, causing serious damage. May cause damage. However, at present, no chemical agent has been found that can be used in box-grown seedlings and exhibits a satisfactory blast control effect. The present inventors have conducted intensive research to overcome the drawbacks of the above-mentioned conventional agents and develop fungicides for agriculture and horticulture.
We have discovered that the purpose can be satisfied by using a mixture of 2,4-triazolo(3,4-b)benzothiazole (hereinafter referred to as EL-291) as an active ingredient, and based on this knowledge, we have made the present invention. I've reached it. That is, the present invention is based on the general formula (In the formula, X represents a halogen atom, a halo-lower alkyl group, or a lower alkyl group, R represents a hydrogen atom, a formyl group, or a lower alkanoyl group, and R' represents a lower alkyl group or a lower alkoxy group. However, X represents a lower alkyl group. When R is a formyl group or a lower alkanoyl group, 2-substituted benzanilide and EL-291 (5-methyl-1,2,
The present invention provides an agricultural and horticultural fungicidal composition containing 4-triazolo(3,4-b)benzothiazole) as an active ingredient. When used alone, the 2-substituted benzanilide represented by the above general formula causes rice rot, rust of various crops,
It is effective in controlling soil diseases and is known to have systemic transferability in plant tissues. However, it has almost no control effect on rice blast at normal spray concentrations. On the other hand, EL―
Although 291 itself shows a preventive effect against rice blast, it shows almost no therapeutic effect at normal spray concentrations. On the other hand, by using a mixture of 2-substituted benzanilide represented by the above general formula and EL-291, the preventive effect against rice blast can be maintained not only when sprayed on foliage but also when treated at the seedling box stage. However, the therapeutic effect can be significantly enhanced, the timing of spraying can be easily set, and the number of treatments can be reduced. The present inventors previously proposed a mixture of EL-291 and 2-methylbenzanilide (Japanese Patent Application Laid-open No.
No. 52-134022) The effects described above were not achieved as the drug damage was still insufficient. Examples of the 2-substituted benzanilide represented by the above general formula used in the fungicidal composition of the present invention include those shown below. These 2-substituted benzanilides are EL-291
and weight ratio of 1:5 to 5:1, preferably 1:1 to
They are used by mixing at a ratio of 3:1. The sterilizing composition of the present invention is prepared by blending these active ingredients with carriers, diluents, surfactants, dispersants, and auxiliaries as required. These are formulated in the form of powders, wettable powders, flowable powders, powders, etc., and are sprayed as they are or after being diluted to an appropriate concentration before use. The composition of the present invention can also be used as a mixed composition or in combination with one of other agricultural chemicals, fertilizers, plant nutrients, etc., depending on the situation where it is applied. For example, when applying the composition of the present invention to seedling boxes to control seedling blast disease, or when controlling rice blast/mongare disease in rice fields, a control agent for rice pests that occur at the same time as this disease (in some cases) It is also possible to mix it with a fungicide (or even a fungicide) to make it a multi-purpose pest control agent. Representative pesticides used for this purpose include the following: For example, bactericidal agents include antibiotics such as plasticidin S and kasugamycin, O,O-diisopropyl S-benzylthiophosphate, O-ethyl S,S-diphenyldithiophosphate, and 4,5,6,7-tetra Examples include synthetic fungicides such as chlorphthalide and diisopropyl 1,3-dithiolan-2-ylidenemalonate. Insecticides include organophosphorus insecticides such as fenitrothion, EPN, diazinon, marathon, dipterex, 1-naphthyl N-methylcarbamate, m-tolyl N-methylcarbamate, 2-sec-butylphenyl N
- Examples include carbamate insecticides such as methyl carbamate, formamidine insecticides such as chlorphenazimine, and other cartaps. The sterilizing composition of the present invention has the following excellent effects. (1) When processed by Honda, EL-291 retains its preventive effects while exhibiting high therapeutic effects against rice blast, Mongare disease, etc. that cannot be predicted from the use of the active ingredient alone. (2) In box-raised rice seedlings, EL-291 can be used therapeutically to control seedling blast and prevent its spread to Honda, and at the same time, the action of EL-291 can prevent leaf blast in Honda. can do. (3) A single treatment with a chemical can control blast disease from growing seedlings in boxes to transplanting seedlings and leaf blast at Honda all at once, saving labor in spraying chemicals. (4) By using EL-291 alone, it is possible to reduce chemical damage such as yellowing of rice seedlings and poor root establishment that normally occurs when seedling boxes are treated. Next, the present invention will be explained in more detail based on examples. The compounds with each number are the respective 2-substituted benzanilides mentioned above, and all percentages are by weight.
shows. Example 1 (Powder) A powder was prepared by uniformly mixing and pulverizing 2.3% of the above compound, 11% of EL-29, 96% of an equal mixture of talc and clay. Example 2 (hydrating agent) Compound 6.50%, EL-29120%, Cane earth 25
%, sodium dodecylbenzenesulfonate 3
% and 2% sodium lignosulfonate were uniformly mixed and ground to prepare a wettable powder. Example 3 (granules) Compound 3.8%, EL-2914%, white carbon 3%, bentonite 20%, talc 41%, clay 20%, sodium lauryl sulfate 1%, sodium lignin sulfonate 3% uniformly The mixture was mixed and pulverized, mixed with a small amount of water, and granulated to prepare a desiccant. Example 4 (Flowable) Compound 9.25%, EL-29125%, ethylene glycol monobutyl ether 4%, colloidal hydrated aluminum silicate fine powder 3%, surfactant and polyoxyethylene alkyl ether, polyoxyethylene nonylphenol A flowable formulation was prepared by mixing and pulverizing a mixture of 10% and sodium alkylbenzenesulfonate and 33% water using a homomixer (TYPE HO-1 manufactured by Tokushu Kika Kogyo Co., Ltd.). Next, the effects of the agricultural and horticultural fungicidal composition of the present invention will be shown using test examples. Test Example 1 (Blast disease treatment efficacy test) Rice seeds (variety Aichi Asahi) in an unglazed drum with a diameter of 12 cm
20 grains of rice are sown, and when the rice reaches the 4th to 5th leaf stage, a suspension of spores of the blast fungus collected from diseased leaves (microscope 150x, field of view 50) is sprayed at 5 cc per seed. Inoculated. Immediately after inoculation, the plants were placed in an inoculation room at 25°C and kept at saturated humidity for two days, and then the honey was taken into the greenhouse and sprayed with the chemicals shown in Table 1. The chemicals were sprayed by diluting each chemical with water and using a turntable and spray gun to spray 20 cc per 3 shots from a distance of 1 m. After the spray solution was air-dried, the bees were placed again in the inoculation chamber at 25°C and saturated humidity, and after 5 days, the number of diseased lesions per 10 leaves was counted, and the therapeutic effect (control value) was calculated using the following formula. The results are shown in Table 1. Treatment effect (control value) = Number of untreated diseases - Number of treated diseases / Number of untreated diseases × 10
0

[Table] Test Example 2 (Blast disease control effect test in a seedling nursery box) Rice fir (variety Aichi Asahi) was sown in a seedling nursery box (1/3 scale of normal rice) and seedlings were raised using a conventional method. 25 days after sowing, a suspension of blast fungus spores collected from diseased leaves (50 spores in a 150 x 150 microscope field) was spray inoculated.
Then, after infecting in an inoculation room at 25℃ every 2 days,
The next morning, a predetermined amount of a hydrating powder prepared in the same manner as in Example 2, except that the compounds shown in Table 2 were used instead of Compound 6 and EL-291, was dissolved in 500 ml of water and poured into a seedling box. Treated (500ml/1 box) and left on a greenhouse bench during the day, placed in a humid room at 25℃ in the evening,
It promoted the onset of rice blast disease. 7 days after vaccination per box
The control value was calculated by counting the diseased stems and diseases of 100 seedlings. On the other hand, in order to observe phytotoxicity after transplantation, 5 hours after the irrigation treatment, some seedlings from each treatment area were placed in white porcelain pots with a diameter of 9 cm in a rice field condition, with 3 stems per pot, and 3 plants each for a total of 5 pots. 10 and 20 days after transplantation, the condition of stem and leaf damage, root condition, and plant height were observed. The results are shown in Tables 2 and 3. However, control value % = (1 - number of diseased insects in treated area/number of diseased insects in untreated area) x 100. The results are shown as the average value of the results of three areas.

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Claims (1)

[Claims] 1. General formula (In the formula, X is a halogen atom, a halo-lower alkyl group, or a lower alkyl group, R is a hydrogen atom, a formyl group, or a lower alkanoyl group, and R' is a lower alkyl group or a lower alkoxy group. (R is a formyl group or a lower alkanoyl group) 2-substituted benzanilide and 5-methyl-1,2,4-triazolo(3,4-b)benzazole are both active ingredients. A disinfectant composition for agricultural and horticultural use.