JPH1129414A - Agricultural/horticultural microbicide - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject microbicide showing an excellent preventive effect on bacterial diseases of plant, highly safe for crops, human, and animals, and useful for a rice seed immersion infectant, seed application agent, soil incorporation agent, and cucumber foliage application agent by including L-4- oxalysine as an active ingredient. SOLUTION: This microbicide is obtained by including L-4-oxalysine or its salt (e.g., mono-or dihydrochloride, mono- or disulfate, etc.) of 0.1 to 90 wt.%. There are applied 0.5 to 10 kg (5 to 1000 g as an active ingredient), pref. 1 to 4 kg based on 10 ares in case of the powdered microbicide and 50 to 500 L (a dilution liquid containing 1 to 10,000 ppm as an active ingredient), pref. 100 to 300 L based on 10 ares in case of the liquid microbicide.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a fungicide for agricultural and horticultural use containing L-4-oxalidine or a salt thereof as an active ingredient.
The present invention relates to an agricultural and horticultural fungicide for controlling bacterial diseases of plants such as rice brown streak and cucumber spot bacterial disease.

[0002]

2. Description of the Prior Art L-4-oxalidine, which is an active ingredient of the agricultural and horticultural fungicide of the present invention, was first synthesized as a lysine antagonist in a racemic form. It has been reported that the racemate exhibits growth inhibitory activity on seven kinds of bacteria on a synthetic medium, and the inhibition is antagonically recovered by lysine [Journal of American Chemical Society (J. Am. Chem. Soc.), Vol. 79,
P.5693 (1957); U.S. Patent No. 2,959,6
No. 14].

[0003] In addition, L-4-oxalidine is obtained from Streptomyces chertlusis.
myces chartreusis) and Streptomyces erythrochromogenes cultures. And Staphylococcus
ccus aureus and Salmonella (Sal)
It has been reported that L-4-oxalidine was intraperitoneally administered to mice infected with C. monella schottmuelleri, but showed no effect (antimicrovial agent chemotherapy (A
antimicrobial Agents and C
Hemotherapy), p. 401, (196)
7)).

Furthermore, it has been described that L-4-oxalidine or a salt thereof exhibits an antibacterial activity against yeasts such as Candida and Saccharomyces (Japanese Patent Laid-Open No. 63-18 / 1988).
No. 3526).

The monohydrochloride or dihydrochloride of L-4-oxalidine is disclosed in Microbiology, Vol. 2, 218
Page (1981).

[0006]

Heretofore, L-4-oxalidine has been known to exhibit antibacterial activity on some bacteria and fungi on a synthetic medium. The control effect on plant diseases caused by infection of these fungi was not known.

On the other hand, inorganic copper agents, TMTD agents, oxolinic acid agents and kasugamycin agents have been widely used as seed disinfectants, seed dispersants and soil admixtures against bacterial diseases of rice. However, the method using these agents is not always sufficient in terms of the control effect on bacterial diseases such as rice seedling blight and the safety against humans and crops. Therefore, there is a demand for the development of a drug which exhibits an excellent effect particularly on bacterial diseases of plants and is highly safe.

An object of the present invention is to provide an agricultural and horticultural fungicide which contains L-4-oxalidine or a salt thereof as an active ingredient, has an excellent control effect on bacterial diseases of plants, and is highly safe for crops and humans. Is to provide.

[0009]

DISCLOSURE OF THE INVENTION The present inventors have studied the effects of various compounds on controlling plant diseases in order to provide an agricultural and horticultural fungicide meeting the above-mentioned object. As a result, they have found that L-4-oxalidine or a salt thereof exerts an excellent control effect on bacterial diseases such as rice seedling blight, and is highly safe for crops and humans.

Accordingly, the gist of the present invention is an agricultural and horticultural fungicide characterized by containing L-4-oxalidine or a salt thereof as an active ingredient.

Next, the agricultural and horticultural fungicide of the present invention will be specifically described. L-4-oxalidine which is an active ingredient contained in the agricultural and horticultural fungicide of the present invention is represented by the following chemical structural formula.

[0012]

Embedded image

L-4-oxalidine can be produced by a known method described in the above literature.

Examples of mono- or di-salts of L-4-oxalidine are shown in Table 1. However, the present invention is not limited to only these examples.

[0015]

[Table 1]

These salts can be produced by reacting L-4-oxalidine with hydrochloric acid, hydrobromic acid or the like according to a conventional method [(Microbiology Bulletin Vol. 21, No. 2, 218). P. (1981)].

The agricultural / horticultural fungicide according to the present invention can be formulated as described below. That is, in order to produce the agricultural and horticultural fungicide of the present invention, L-4-oxalidine or a salt thereof used in the present invention is mixed with a suitable carrier and various other auxiliaries for agrochemicals and mixed. Depending on the method, wettable powders, emulsions, liquids, sols (flowables), oils, powders, coarse powders, DL (driftless) powders, flow dusts, fine granules, fine granules, granules, tablets, sprays Agent and the like. However, the dosage forms that can be formulated in the present invention are not limited to those listed here.

The content of the active ingredient in these preparations can be appropriately changed depending on the conditions such as the form of the preparation and the method of application. Generally, it is desirable to use it in a formulation within a range of 0.1 to 90% (% by weight, the same applies hereinafter).

Various auxiliaries for agricultural chemicals are used for the purpose of improving the control effect, stabilization, dispersibility and the like of agricultural and horticultural fungicides. Such adjuvants include carriers (diluents), spreading agents, emulsifiers, wetting agents, dispersants, surfactants as disintegrants, antioxidants, and ultraviolet inhibitors. As the carrier, any solid or liquid carrier can be used as long as it is commonly used in agricultural and horticultural medicines, and is not limited to a specific carrier.

For example, solid carriers include mineral powders (kaolin, bentonite, clay, montmorillonite, talc, vermiculite, gypsum, calcium carbonate, white carbon, silica sand, ammonium sulfate, urea, etc.), vegetable powders (starch, crystalline cellulose) ), High molecular compounds (such as petroleum resins), alumina, silicates, sugar polymers and the like.

Examples of the liquid carrier include water, alcohols (eg, methanol, ethanol, n-propanol, ethylene glycol, and glycerin), ethers (eg, tetrahydrofuran), ketones (eg, methyl ethyl ketone, cyclohexanone), esters, and nitriles. , Sulfoxides (such as dimethyl sulfoxide), alcohol ethers (such as ethylene glycol monomethyl ether and ethylene glycol monoethyl ether), aliphatic or alicyclic hydrocarbons (such as cyclohexane), industrial gasoline (such as solvent naphtha), and Petroleum fractions and the like.

In the preparation of emulsions, wettable powders, flowables (sols) and the like, a surfactant (or emulsifier) is used for the purpose of emulsification, dispersion, solubilization, wetting, foaming, lubrication, spreading and the like. used. Examples of such surfactants include nonionic types (polyoxyethylene alkyl ether, polyoxyethylene alkyl ester, polyoxyethylene sorbitan alkyl ester, sorbitan alkyl ester, etc.) and anionic types (alkylbenzene sulfonate, alkyl sulfosuccinate, Alkyl sulfate, polyoxyethylene alkyl sulfate, aryl sulfonate, etc., cationic type (alkylamines [laurylamine, stearyltrimethylammonium chloride, alkyldimethyldibenzylammonium chloride, etc.], polyoxyethylene alkylamines, etc.), amphoteric type (Carboxylic acid [betaine type],
And the like, but of course, the invention is not limited only to these examples.

Examples of the spreading agent include polyoxyethylene nonylphenyl ether and polyoxyethylene lauryl ether. Examples of the wetting agent include polyoxyethylene nonyl phenyl ether, dialkyl sulfosuccinate and the like. Examples of the fixing agent include carboxymethyl cellulose (CMC) and polyvinyl alcohol (PVA). Examples of the disintegrant include sodium ligninsulfonate and sodium lauryl sulfate.

In addition to these, various adjuvants such as gum arabic, gelatin, casein, sodium alginate, tragacanth, and xanthan gum can be used.

[0025]

Next, working examples of the formulation of the fungicide for agricultural and horticultural use of the present invention will be described. However, the amount of the active ingredient contained in the agricultural and horticultural fungicide of the present invention, the type of the carrier and the auxiliary agent, and the amount of the additive are not limited to the following examples.

In the examples, all parts are parts by weight, and all parts are by weight.

Example 1 (Powder) 2 parts of L-4-oxalidine, PAP (physical property improving material) 1
Parts and 97 parts of clay are uniformly mixed and pulverized to obtain a powder containing 2% of the active ingredient.

Example 2 (Wettable powder) 30 parts of L-4-oxalidine monohydrochloride, 3 parts of calcium alkylbenzenesulfonate, 5 parts of polyoxyethylene nonylphenyl ether and 62 parts of clay are uniformly mixed and pulverized. A wettable powder containing 30% of the active ingredient is obtained.

Example 3 (Wettable powder) 30 parts of L-4-oxalidine, 3 parts of calcium alkylbenzenesulfonate and 30 parts of polyoxyethylene nonylphenyl ether are uniformly mixed and dissolved to contain 30% of an active ingredient. Obtain wettable powder.

Example 4 (Emulsion) 30 parts of L-4-oxalidine monoacetate, 40 parts of methyl ethyl ketone, and 30 parts of polyoxyethylene nonylphenyl ether were uniformly dissolved and mixed to obtain an emulsion containing 30% of an active ingredient. obtain.

Example 5 (granules) 5 parts of L-4-oxalidine monohydrochloride, 1.5 parts of lauryl sulfate, 1.5 parts of calcium ligninsulfonate
Parts, 25 parts of bentonite and 67 parts of white carbon are uniformly mixed, 15 parts of water is added thereto, and the mixture is kneaded with a kneader, granulated with a granulator, and dried with a fluidized drier. % Granules are obtained.

Example 6 (Sol) 40 parts of L-4-oxalidine monohydrochloride, 2 parts of lauryl sulfate, sodium alkylnaphthalenesulfonate 2
Parts, 1 part of hydroxypropylcellulose and 55 parts of water are uniformly mixed to obtain a sol containing 40% of the active ingredient.

The fungicide for agricultural and horticultural use of the present invention is used in combination with other fungicides, insecticides, herbicides, acaricides, nematicides, fertilizers, soil improvers, etc., in addition to the active ingredient. You can also. Then, by the combination, the applicability (applied disease, method of use, time of use, etc.) can be expanded, and in some cases, a synergistic control effect can be expected by synergistic action of the respective active ingredients.

The method for applying the agricultural and horticultural fungicide of the present invention is generally as follows. That is, the application rate varies depending on various factors, for example, the target disease, its occurrence status, weather, dosage form, application method, application place, application time, but generally, powder, coarse powder, DL powder, flow dust, fine granule , 0.5 for 10 ares for fine granules, granules and tablets
kg to 10 kg (5 to 1000 g as an active ingredient),
It is preferably applied to the foliage of the disease-causing site of the plant, the soil surface, in the soil or on the water surface using an appropriate sprayer in the range of 1 to 4 kg.

In the case of liquid preparations, emulsions, sol preparations (flowable preparations), oil preparations, hydrated granules and hydration preparations, these are diluted 50 to 10,000 times with water, and the active ingredient is generally 1 to 10,000 ppm. Is prepared at a concentration of The diluted solution is sprayed on the foliage of the disease-causing site of the plant in the range of 50 to 500 liters, preferably 100 to 300 liters per 10 ares.

Liquids, emulsions and sols (flowables)
In the case of (1), the concentrated undiluted solution is not diluted with water, or is diluted with water to within 50-fold, and is mainly used for micro-spraying (U
LV), a small amount of liquid agent spraying (LV spraying), and a liquid agent spraying (S spraying) are sprayed in an amount of 50 to 5000 ml per 10 ares using a helicopter or the like.

In order to use the agricultural and horticultural fungicide of the present invention as a rice seed disinfectant, a general method of using a seed disinfectant may be used. That is, the wettable powder, emulsion and sol (suspension and flowable) containing L-4-oxalidine of the present invention are diluted with water to obtain an active ingredient concentration of 50 to 50,000.
ppm, preferably 500 to 20,000 ppm, and immerse the seed rice in this solution for 10 to 60 minutes (short-time immersion), or for 24 to 48 hours (long-time immersion), or the active ingredient concentration. 5000 to 4
This chemical solution can be subjected to slurry treatment on the surface of seed rice by adjusting to 0000 ppm. In addition, a method such as applying a powdery wettable powder to the surface of the seed rice with a dressing process can also be used.

When the agricultural and horticultural fungicide of the present invention is used as a rice seed dispersant, the wettable powder, emulsion and sol (flowable) containing L-4-oxalidine or a salt thereof of the present invention are used. Dilution in water, the active ingredient concentration is 100 ~ 1
0000 ppm, preferably 1000-4000 ppm
This chemical solution is sprayed from above the seedling box after sowing rice seed paddy with a common sprayer, or 30 to 200 ml is sprayed, or 300 to 1 with a mug or the like.
It can be applied by a method such as irrigating 0000 ml. In addition, dust or granules containing the L-4-oxalidine or a salt thereof of the present invention can be used for 10 to 5 hands or a general spraying machine from above the seedling box after sowing rice seeds.
It can be applied by a method such as spraying 0 g.

When the agricultural and horticultural fungicide of the present invention is used as a soil admixture, the powder or granule containing the L-4-oxalidine or a salt thereof of the present invention may be used as it is per 5 liters of the seedling culture soil. It can be applied by a method such as mixing 10 to 50 g.

Next, test examples will specifically show that the agricultural and horticultural fungicides of the present invention have fungicidal activity against plant pathogenic bacteria.

Test Example 1 (Test of seed disinfection effect for controlling rice seedling bacterial wilt) Pseudomonas plant was used as a test paddy at the flowering stage of rice (variety: Kirara 397).
An infected rice paddy rice bacterial wilt disease was collected by spraying and inoculating a concentrated bacterial suspension (10 ⁴ / ml) of Ari).
The seed disinfectant was prepared by diluting L-4-oxalidine monohydrochloride or a control agent to a predetermined concentration with water.

To this chemical solution, rice seedling-infected bacterial disease-infected paddy was added such that the volume ratio (v / v) of the seed rice to the chemical solution was 1: 1, and the seed rice was disinfected at 20 ° C. for 24 hours. did. Seed after disinfection is soaked in water at 20 ° C for 3 days,
The water was drained and germinated at 30 ° C for 24 hours. Then, the pigeon-chested seed paddy is seeded on Kumiai granular soil K (manufactured by Kureha Chemical Industry Co., Ltd.) according to the conventional box raising method,
Sprouted for days. After that, cultivation was managed in a glass greenhouse. This test was conducted in three sections per section.

At 21 days after sowing (four leaf stage), all rice seedlings in each treatment plot were sampled, and the number of diseased seedlings and healthy seedlings of rice seedling blight disease were investigated according to the following criteria (1). Determine the disease severity (%) by the following formula,
The control value (%) was calculated.

The degree of phytotoxicity to rice was observed by observing the degree of growth and the rate of emergence, and displayed based on the following phytotoxicity index. Table 2 shows the test results.

Disease Investigation Criteria N ₀ : Number of Non-Affected Seedlings N ₁ : Number of Seedlings with Symptoms of Bleaching Symptoms in First or Second Leaf N ₂ : Whether Growth is Suppressed Or the number of seedlings that have decayed

Investigation index of phytotoxicity 5: severe, 4: severe, 3: many, 2: slightly, 1: slight,
0: None

[0047]

(Equation 1)

[0048]

[Table 2]

Test Example 2 (Test for Effect of Spraying Treatment after Seeding for Control of Rice Seedling Blight Disease) The same test paddy as in Test Example 1 was used. The rice seedling-infected bacterial disease-infected paddy was immersed in water at 20 ° C. for 3 days, then drained and germinated at 30 ° C. for 24 hours. Then, after seeding the seedlings in the shape of a pigeon chest on the Kumiai granular cultivation soil K in accordance with a conventional box raising method, the treated chemical is applied to the seedling box (30 × 60 cm) in a volume of 5 × 10 cm.
0 ml was sprayed, and the soil was covered with a dried seedling culture. Embryos were germinated at 32 ° C. for 2 days, and then cultivated and managed in a glass greenhouse.

The disease investigation and phytotoxicity were investigated according to the same investigation criteria as in Test Example 1, and the diseased seedling rate (%) was the same as in Test Example 1.
And the control value (%) was calculated. Table 3 shows the results.

[0051]

[Table 3]

Test Example 3 (Test for controlling bacterial spot of cucumber spot) Pseudomonas syrup
ringae pv. Lachrymans) is cultured on a liquid medium (composition; liquid medium of Test Example 1 to which 20 g of agar is added) for 2 days. The grown cells are collected with sterile water, and diluted with sterile water so that the number of cells becomes 10 ⁸ cells / ml.

A predetermined concentration dilution of a wettable powder prepared according to Example 2 to the second leaf stage seedling of cucumber (cultivar: Sagami Hanjiro) cultivated in a greenhouse in a plastic pot having a diameter of 6 cm. Using an automatic spraying device, 10
ml. On the day after the chemical treatment, 40 ml per pot of a previously prepared inoculum of the bacterial disease of cucumber spot was spray-inoculated on the back of the cucumber using a spray gun. Then, put the cucumber seedlings in a pot at 24 ° C. and 90% humidity in a pot and cover them with a vinyl cover.
After keeping for 2 days, they were transferred to a greenhouse at 24 ° C. to promote the onset of the disease. Six days after the inoculation, the percentage of cucumber spot bacterial disease-causing lesion area per leaf (%) was investigated, the average disease-causing lesion area percentage (%) was determined, and the control value (%) was calculated by the following formula.

[0054]

(Equation 2)

This test was carried out in a three-pot system per one solution concentration, and the average control value (%) was determined and converted to the control value according to the following evaluation criteria.

[0056]

Further, the phytotoxicity to cucumber was investigated according to the same criteria as in Test Example 1. Table 4 shows the results.

[0058]

[Table 4]

[0059]

According to the present invention, the following effects can be obtained. That is, if the agricultural and horticultural fungicide of the present invention is used as a rice seed immersion disinfectant, a seed dispersant or a soil admixture, rice seedling blight bacterial disease, rice seed blight bacterial disease,
It exerts a stable and high seed disinfecting effect against rice brown streak and can effectively control these diseases.

When the fungicide for agricultural and horticultural use of the present invention is used as a foliar spray, it exhibits a high control effect on bacterial diseases such as cucumber spot bacterial disease.

Further, the active ingredient according to the present invention has extremely low toxicity (oral:> 1000 mg / kg), has good biodegradability of the active ingredient, and has almost no environmental pollution.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yasushi Yashiro 2-3-31-301 Yoshihara, Higashiosaka-shi, Osaka (72) Inventor Kazuyoshi Arita 9 Eminence Nibankan 201, 2203 Shimogasuya, Isehara-shi, Kanagawa issue

Claims (1)

[Claims] 1. A fungicide for agricultural and horticultural use characterized by containing L-4-oxalidine or a salt thereof as an active ingredient.