JPH0460443B2 - - Google Patents

Description

[Detailed description of the invention]

INDUSTRIAL APPLICATION FIELD The present invention relates to an agricultural and horticultural fungicide for controlling plant pathogenic bacteria that cause great damage to various crops such as vegetables, fruit trees, and rice. More specifically, the active ingredients include kasugamycin or its salts (hereinafter abbreviated as KSM) and 3,3-dimethyl-1-(4-phenylphenoxy)-1-(1 , 2,4-triazol-1-yl)-2-butanol (hereinafter abbreviated as biteltanol) as an active ingredient. Therefore, the present invention can be effectively used as a fungicide in the field of agricultural chemicals and horticulture to control plant diseases. biteltanol Prior Art KSM, one of the active ingredients of the present invention, is known as an agricultural fungicide and is widely used as a control agent for various diseases such as rice blast, tomato leaf mold, and beet brown spot. It has extremely low toxicity to humans, livestock, fish and shellfish. These matters are described in Japanese Patent Publication No. 42-6818, Publication No. 21757-1977,
No. 162 of “Pesticide Handbook 1981 Edition” (Japan Plant Protection Association, published July 20, 1981)
~Page 164, “Japanese Society of Plant Pathology Bulletin No. 34”
Page 392 (1968), described on pages 454 to 461 of "Commissioned Test Results (Volume 21) Vegetables, etc. (Fungicides)" (Japan Plant Protection Association, published in December 1976) . In addition, it is also used as a control agent for various diseases by mixing it with other fungicidal ingredients, for example, in Japanese Patent Publication No. 54-32053 (mixture of KSM and basic copper chloride), Japanese Patent Publication No. 57-21306. Publication (KSM and
It is known as a mixture with EDDP).
(The drug names in the box are from “Pesticide Handbook 1981
This is the common name listed in the Annual Edition). On the other hand, biteltanol is a known compound that is effective in controlling powdery mildew and rust of various crops, scab of fruit trees, scab of fruit trees, drought spot of beets, and the like. This is described in JP-A No. 54-59277, "Commissioned Test Results (Volume 28) Vegetables, etc. (Fungicides)". In addition, it is extremely safe for human hoarding, fish and shellfish, and can control various types of powdery mildew, rust, and scab on fruit trees with low-dose spraying, so there is no need to worry about environmental pollution. It is an excellent drug.
However, the effect on beet brown spot is rather weak, and in order to obtain an effective control effect, it is necessary to spray at a higher dose than usual. Problems to be Solved by the Invention Many agricultural and horticultural fungicides have been developed and used so far. However, as a result of the use of disinfectants such as thiophanate methyl and benomyl many times over many years, pathogenic bacteria (resistant bacteria) have developed that are resistant to these disinfectants, and these disinfectants are no longer effective. For example, it has become difficult to control powdery mildew in various crops, scab in fruit trees, gray mold in vegetables, brown spot in beets, etc., and new agents are being developed to replace these. However, for example, no new and highly effective agent for controlling beet brown spot caused by resistant bacteria has yet to be found. Therefore, a bactericide containing triphenyltin hydroxide as an active ingredient is currently being used as an alternative, but there are some concerns regarding its safety. In this way, the reality is that we are struggling to take measures to control plant diseases caused by resistant bacteria. Therefore, there is a desire to develop a drug that is highly effective against diseases caused by resistant bacteria, which is currently a problem, has low toxicity to human stock, fish and shellfish, and is not a concern for the environment. There is. The object of the present invention is to provide a novel agricultural and horticultural fungicide to meet such demands. Means, Action, and Effect for Solving the Problems The inventors of the present invention have conducted extensive research in consideration of the above points, and have found that a two-component fungicide consisting of KSM and bitertanol meets the purpose and is extremely effective. I discovered that. The agricultural and horticultural fungicide of the present invention is suitable for use in powdery mildew of various crops, mildew, scab disease of fruit trees, brown spot of beetroot, brown leaf spot of tomato, leaf spot of cucumber, bacterial spot of cucumber, and soot of eggplant. It is effective in controlling diseases such as brown leaf spot, brown leaf spot, and rice blast, and has a particularly high synergistic effect against beet leaf spot, which is difficult to control due to the emergence of resistant bacteria. This is remarkable and exceeds expectations based on usage alone. In this case, looking at the relationship between the blending ratio of active ingredients and the control effect, if 2 to 20 parts by weight of bitertanol is blended to 1 part by weight of KSM, it will have a high synergistic effect against beet brown spot, etc. However, 3 to 3 parts of biteltanol per 1 part by weight of KSM
The highest synergistic effect is obtained when mixed at a ratio of 10 parts by weight. In order to exhibit such excellent effects,
By directly spraying the agricultural and horticultural fungicide of the present invention on plant foliage using an appropriate spraying device before or after disease outbreak, target diseases can be effectively controlled, and useful crops can be For example, it does not cause any chemical damage to cucumbers, tomatoes, eggplants, beets, Japanese cabbage, tomatoes, tea, rice, etc. In addition, the agricultural and horticultural fungicides of the present invention include benzimidazole drugs such as benomyl and thiophanate methyl, which are currently problematic, and pinlozolin, procymidone, and iprodione (all of which are common names), as described in the above-mentioned Pesticide Handbook 1981. Dicarboximide drugs such as those described in the 2015 edition contain bitertanol, a new drug with a completely different chemical structure, as part of its active ingredient. Therefore, it acts on resistant bacterial diseases caused by benzimidazole drugs and dicarboximide drugs as effectively as, or even more effectively, than the disease control effect caused by susceptible bacteria. The agricultural and horticultural fungicide of the present invention can be used by formulating it into wettable powders, powders, granules, emulsions, flowables (sols), etc., by a conventional method together with the active ingredient, a carrier, and various auxiliaries. The carrier used is
Solid carriers such as clay, talc, bentonite, kaolin, diatomaceous earth, silica, etc., or benzene, xylene, toluene, kerosene, alcohols (methanol, ethanol, isopropanol, n-butanol, etc.), ketones (acetone,
Liquid carriers such as methyl ethyl ketone, cyclohexanone, etc.) are used. These can be formulated with appropriate amounts of surfactants and other auxiliary agents, such as stabilizers and spreading agents, for use. The appropriate blending ratio of the active ingredients in the present invention is 2 to 20 parts of bitertanol per 1 part of KSM, but preferably,
The ratio of bitertanol to 1 part by weight of KSM is 3 to 10 parts by weight. However, the blending ratio can be changed as appropriate depending on the conditions at the time of use. Further, other fungicides, insecticides, herbicides, plant growth regulators, etc. can also be mixed and used. Examples Next, examples of the present invention will be shown. In addition, all parts in the examples are parts by weight. Example 1 (hydrating agent) KSM 4 parts, bitertanol 16 parts, white carbon 2 parts, lauryl sulfate 3 parts,
Naphthalene sulfonic acid sodium formalin condensate
2 parts and 73 parts of clay were mixed and thoroughly ground.
Obtain a hydrating powder. Example 2 (hydrating agent) KSM 5 parts, bitertanol 25 parts, white carbon 2 parts, lauryl sulfate 3 parts,
Naphthalene sulfonic acid sodium formalin condensate
2 parts and 63 parts of finely powdered clay are mixed and thoroughly ground to obtain a wettable powder. Example 3 (Powder) 0.3 parts of KSM, 2.0 parts of bitertanol, isopropyl acid phosphate (physical property improver)
Mix 0.2 parts and 97.5 parts of clay and grind thoroughly.
Get the powder. Test Example The disease control effect of the agricultural and horticultural fungicide of the present invention will be explained by a test example. Test Example 1 Beet Brown Spot Disease Control Effect Test (Pot Test) When the fourth leaf of beet (variety Hirabe) sown in a clay pot with a diameter of 9 cm developed, a hydrating powder prepared according to Example 1 was applied as prescribed. The solution was diluted to a specific concentration and sprayed on a turntable with a spray gun to 30ml per 3 pots. The inoculum source was infected leaves that had been inoculated with thiophanate methyl resistant bacterial spores and infected with 2
The cells are placed in a humid room for several days to form spores, which are then treated with a spreading agent (polyoxyethylene alkyl ether).
A spore suspension made from a 50 ppm solution was used. After adjusting the spore concentration to 10 ⁶ spores/ml, the mixture was spray-inoculated onto plants one day after spraying. 25℃ and humidity after inoculation
After being left in a 100% humidity room for 2 days, they were transferred to a glass greenhouse and infected. To investigate the onset of disease, the number of lesions per leaf was investigated 16 days after inoculation with the pathogen, and the control value (%) was calculated from this comparison with the unsprayed area. In addition, the degree of drug damage to beets was expressed using the following drug damage index. Control value (%) = (1 - Average number of lesions per leaf in treated area / Average number of lesions per leaf in untreated area × 100 Plant damage index 0 = No damage 2 = Medium 4 = Severe 1 = Slight 3=many

【table】

[Table] Test example 2 Beet brown spot control effect test (field test) Test method (1) Test variety: Monohill (2) Ward system: 1 section 5 m ² , 3-row system (3) Chemical application amount/method: Using a wettable powder prepared according to Example 1, the first spraying was performed on July 3rd, and then a total of three times at 15-day intervals. The amount of chemical sprayed was equivalent to 200 per 10 ares, and a shoulder sprayer was used. (4) Occurrence status of the target disease: At the time of the first spraying, initial lesions were already observed on the lower leaves, but in order to spread the disease uniformly, the diseased leaves were crushed and 10g per plot was added to the ridge. As the inoculation was spread over a period of time, there were many outbreaks. (5) Disease outbreak investigation: On August 20th, all plants in each area were investigated according to the following survey criteria to determine the disease severity, and control was determined by comparing with the non-sprayed area. The value (%) was calculated. Disease investigation criteria Disease index: 0 No lesions 1 Less than 10% of the leaf area is affected 2 More than 10% of the leaf area is less than 40% affected 3 More than 40% of the leaf area is less than 70% affected 4 More than 70% of the leaf area is affected Disease severity = = (Infection index x number of plants) / 4 x Total number of tested plants x 100 Control value (%) = (1 - disease severity in sprayed plots / disease severity in non-sprayed plots) x 100 Regarding chemical damage, it is important to check with the naked eye. Observations were made using the same index as in Test Example 1. The results are shown in Table 2.

【table】

Claims (1)

[Claims] 1. Kasugamycin or its salts and 3,3-dimethyl-1-(4-phenylphenoxy)-1-
An agricultural and horticultural fungicide characterized by containing (1,2,4-triazol-1-yl)-2-butanol as an active ingredient. 2. The agricultural and horticultural fungicide according to claim 1, wherein the agricultural and horticultural fungicide is a fungicide for beet brown spot.