JP2002145708A - Plant disease injury controlling agent - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a plant disease injury controlling agent exhibiting high efficacy at low levels on various disease injuries, particularly wheat glume blotch and cucumber gray mold and the like, and having high safety to plants. SOLUTION: This plant disease injury controlling agent comprises copper pyrithione as the active ingredient.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a plant disease control agent which is extremely effective for controlling disease on agricultural and horticultural crops.

[0002]

2. Description of the Related Art Plant diseases are a great obstacle to the stable supply of agricultural products. In recent years, plant diseases have become a serious problem in order to secure food that supports an expanding population. There is a need for more efficient and more effective drugs.

[0003] Fusarium wilt, which is one of the representative diseases of wheat, which is a major crop in the world, does not have an agent that is effective in controlling, and has recently become a serious problem as an intractable disease. Azoxystrobin, tebuconazole and the like are known as agents for controlling this disease, but their control effects are not sufficient, and cases have been reported in which the disease cannot be actually controlled. At present, there is no drug that shows a sufficient control effect against this disease,
A drug having a stable control effect is desired.

[0004] Gray mold, which is a typical disease of many crops, has a high frequency of resistant bacteria and is one of the diseases that are difficult to control. For example, since benzimidazole-based or dicarboximide-based drugs have been used for gray mold of cucumber, strawberry, grape or the like for many years, drug-resistant bacteria have emerged, and this has become a major problem. For these reasons, there is a strong demand for a drug having a novel action that can provide a stable disease control effect.

[0005] The present invention uses copper pyrithione as an active ingredient of a plant disease controlling agent. Copper pyrithione is a known compound described in the method for producing copper pyrithione (Japanese Translation of PCT International Publication No. 9-506903), and is known as a chemical to be added to paints to prevent ship bottom pollution, but is used for agricultural products. It has not been reported as a plant disease control agent.

[0006] In addition to copper pyrithione, zinc pyrithione, sodium pyrithione, dipyrithione and the like are known. Among them, zinc pyrithione has been tested as a seed disinfectant, but its effect is not sufficient. For example, the control effect against black rot of Brassicaceae only reduces the incidence of disease-free seeds by about 60% (Plant Disease
s, Vol. 70, No. 11, p. 1027). In addition, according to the test report as a soil treatment agent, no effect was recognized at all even at a high dose of 20,000 ppm (Pesticides, Vol. 19, No. 8, 56-57).
page). Although sodium pyrithione has been reported as a fungicide for agriculture, it is not practical because of strong chemical damage to plants. For example, it has been reported that the foliage application at a concentration of 700 ppm on cucumber caused a strong phytotoxicity, and the subsequent tests had to be stopped (Journal of Phytopatholog
y, Vol. 121, No. 4, p. 325). That is, it can be seen that compounds such as zinc pyrithione, sodium pyrithione, and dipyrithione have a low disease control effect on plants and are more phytotoxic, and thus are difficult to put into practical use.

[0007]

DISCLOSURE OF THE INVENTION The present invention is a plant control agent having a high control effect on many plant diseases, especially a high control effect on wheat blight and gray mold, and having high safety. The purpose is to provide.

[0008]

Means for Solving the Problems To solve these problems, the present inventors have synthesized or obtained a large number of novel compounds and known compounds, and as a result of extensive research, have found that copper pyrithione is found to be among many compounds. In particular, it showed high control effect at low concentration on wheat blight, gray mold on vegetables and fruit trees, high safety against plants, and high control effect on various plant diseases. Completed the invention.

That is, the present invention provides the following formula [1]

[0010]

[Formula 1]

A plant disease controlling agent containing copper pyrithione as an active ingredient. Copper pyrithione is a green powder that has a broad spectrum of activity that is effective against various plant diseases, especially against wheat blight, which is an intractable disease of barley, and gray mold on vegetables and fruit trees. It has an excellent control effect.

The plant disease controlling agent of the present invention has a wide variety of plant diseases exhibiting a disease controlling effect, has a high disease controlling effect, and has high safety against agricultural crops.

In particular, it has a high disease control effect against wheat blight, which is an intractable disease, and gray mold, which is a problem with resistant bacteria, and has excellent characteristics that are not present as conventional plant disease control agents. .

When the compound used in the present invention is used as a plant disease controlling agent, the active ingredient may be used as it is, but depending on the purpose, the active ingredient may be used in the form of granules, powders, and the like usually used in agricultural chemicals. It is used in the form of a wettable powder, suspension preparation, emulsion or the like. These preparations are usually prepared by diluting the active ingredient with an inert liquid or solid carrier and adding a surfactant and other auxiliaries as necessary.

The formulation ratio of the active ingredient in these preparations is
Depending on the target disease, other conditions, etc., it is usually 0.1 to 20% (weight) for powders and granules, and 5 to 80% (weight) for emulsions and wettable powders and suspensions. ) Is appropriate. Suitable carriers include, for example, talc, bentonite, clay, kaolin, diatomaceous earth, white carbon, vermiculite, slaked lime, silica sand, ammonium sulfate, urea, and other solid carriers, water, isopropyl alcohol, xylene, cyclohexanone, methylnaphthalene, alkylene glycol, and the like. Liquid carrier and the like. As the surfactant and dispersant, for example, dinaphthyl methanesulfonate,
Alcohol sulfates, alkylaryl sulfonates, lignin sulfonates, polyoxyethylene glycol ethers, polyoxyethylene alkylaryl ethers, polyoxyethylene sorbitan monoalkylates and the like. Auxiliaries include carboxymethylcellulose, polyethylene glycol, propylene glycol, gum arabic, xanthan gum and the like.

The preparation for controlling plant diseases of the present invention can be used by directly applying these preparations or diluting them. The application rate of the preparation depends on the target disease, target crop,
It fluctuates depending on the tendency of occurrence, degree of damage, environmental conditions, dosage form used, and the like.

When the plant disease controlling agent of the present invention is used for controlling blight and gray mold, an excellent controlling effect can be obtained at a low concentration.

For example, when foliar application is used for wheat blight, etc., a high control effect can be expected at an active ingredient concentration of 10 to 100 ppm, but when comprehensive control with other diseases is considered. Has a concentration of 10 to 100 ppm or more, that is, 100 to 3,000 ppm.
It is preferable to use in the range of 0 ppm.

When used as such as dusts and granules for the purpose of comprehensive control, the active ingredient is appropriately selected from the range of 0.1 g to 5 kg, preferably 1 g to 1 kg per 10 ares. I do. When used in the form of a liquid such as an emulsion or a wettable powder, it is appropriately selected from the range of 10 ppm to 10,000 ppm, preferably 100 to 3,000 ppm.

The compounds used in the present invention may be used according to the above-mentioned application forms, such as alga fungi (Oomycetes) and ascomycete fungi (Ascomycete).
s), Basidiomycetes, and incomplete fungi (D
euteromycetes), and can control plant diseases caused by fungi and bacteria.

Next, specific bacterial names will be given as examples.
The present invention is not limited by these examples.

Pseudoperonospor
a) Genus fungi such as cucumber downy mildew (Pseudoperonospora)
cubensis), a bacterium of the genus Venturia, for example, a scab of apple (Venturia inaequalis), a bacterium of the genus Erysiphe, for example, a fungus of powdery mildew (Erysip)
he graminis), Pyricularia,
For example, rice blast fungus (Pyricularia oryzae), Botrytis (Botrytis) genus bacteria, such as cucumber gray mold fungus (Botrytis cinerea), Rhizoctonia (Rhizoctonia)
Genus bacteria, such as Rhizoctonia solani, Puccinia genus bacteria, such as wheat rust (Puccinia recondita), Septoria genus bacteria, such as wheat wilt (Septoria nodorum), sclerotinia (Sclerotinia) genus bacteria, such as cucumber sclerotia rot (Sclerotinia sclerotiorum),
ium), for example, Pythium debar
yanum Hesse), and as a bacterium, Burkholderia (B
urkholderia), such as bacterial seedling blight (Burkholderi)
a plantarii).

Further, the compound of the present invention may be mixed with an insecticide, other fungicides, herbicides, plant growth regulators, fertilizers and the like, if necessary.

Next, the preparation method will be described in detail with reference to typical preparation examples of the plant disease controlling agent of the present invention, but the present invention is not limited to these examples. In the following description, “%” indicates weight percentage.

Formulation Example 1 Wetting agent 50% of copper pyrithione, 45% of diatomaceous earth, 2% of sodium dinaphthylmethanedisulfonate and 3% of sodium ligninsulfonate are uniformly mixed and pulverized to obtain a wettable powder.

Formulation Example 2 Suspension Formulation Copper pyrithione 10%, sodium dodecylbenzenesulfonate 4%, polyoxyalkylene allyl phenyl ether 4%, xanthan gum 0.4%, ethylene glycol 15% and water 66.6% Mix and grind to form a suspension formulation.

Formulation Example 3 Granules 5% copper pyrithione, 2% sodium salt of lauryl alcohol sulfate, sodium lignin sulfonate
5%, carboxymethylcellulose 2% and clay 8
6% is uniformly mixed and pulverized. 20% of water was added to the mixture and the mixture was kneaded, processed into granules of 14 to 32 mesh using an extrusion granulator, and then dried to obtain granules.

Next, the effects of the plant disease controlling agent of the present invention will be described specifically with reference to test examples, but the present invention is not limited to these examples.

Test Example 1 Wheat Blight Prevention Effect Test Ten wheat seeds (variety: Norin 61) were sowed in each plastic pot having a diameter of 6.0 cm, and grown in a greenhouse. To the wheat seedlings in which the second leaves were developed, the wettable powder of Formulation Example 1 was diluted with water so as to have the respective active ingredient concentrations, and sprayed at 10 ml per pot. After air-drying, wheat blight fungus (Septoria
nodorum) and inoculated in a greenhouse. Inoculation
Ten days later, the diseased area of the first leaf in the whole pot was examined, evaluated according to the following equation 1, and the control value was determined according to equation 2. As controls, azoxystrobin and tefconazole, which are commercially available drugs used for controlling wheat blight, were used. Table 1 shows the test results. Untreated disease severity is 9
It was 8.6%.

In Equation 1, N0 is the number of healthy leaves, N1 is the diseased area 5
%, The number of leaves is 5% or more but less than 33.3%, the number of leaves is 33.3% or more and less than 66.6%, and the number of leaves is 46.6% or more.

[0031]

(Equation 1)

[0032]

(Equation 2)

[0033]

【table 1】

Test Example 2 Test for Preventive Effect of Cucumber Gray Mold Four cucumber seeds (variety: Sagami Hanshiro) were sowed in each plastic pot having a diameter of 6 cm and grown in a greenhouse. The wettable powder of Formulation Example 1 was diluted with water to each active ingredient concentration to the cucumber seedlings in which the cotyledons had developed, and 10 ml per pot was sprayed. After air drying, a paper disc soaked with a spore suspension of cucumber gray mold fungus (Botrytis cinerea) was placed on the surface of the cucumber cotyledon, inoculated on the surface, and then maintained in a 20 ° C moist chamber. Three days after the inoculation, the diseased area of cotyledons in the entire pot was investigated and evaluated according to the same criteria as in the wheat blight test.
As a control, azoxystrobin, iprodione and fludioxonil, which are commercially available drugs used for controlling cucumber gray mold, were used. Table 2 shows the results.

[0035]

[Table 2]

[0036]

EFFECTS OF THE INVENTION The plant disease controlling agent of the present invention includes wheat blight, cucumber gray mold, cucumber downy mildew, wheat powdery mildew, rice blast, rice sheath rust, wheat leaf rust,
It has a high control effect on a wide range of diseases such as cucumber sclerotium. In particular, it has an excellent control effect against wheat blight and cucumber gray mold, does not cause phytotoxicity to crops, and is useful as a plant disease control agent.

Claims (3)

[Claims] 1. A plant disease control agent comprising copper pyrithione as an active ingredient. 2. The cereal plant disease controlling agent according to claim 1. 3. The plant disease controlling agent according to claim 1, wherein the plant disease is blight or gray mold.