JPS61204105A - Controlling agent against blast of rice plant - Google Patents

Abstract

PURPOSE:The titled controlling agent, containing methyl 9-hydroxyoctadec-10- en-12-ynecarboxylate as an active constituent and useful for controlling blast occurring in paddy fields, particularly leaf blast without toxicity to rice plants. CONSTITUTION:A controlling agent against blast of rice plants containing methyl 9-hydroxyoctadec-10-en-12-ynecarboxylate as an active constituent. In practical use, the above-mentioned constituent may directly be used without adding other constituents, and is usually mixed with a solid carrier, liquid carrier, surfactant or another formulation adjuvant and formulated into an emulsion, wettable powder, suspension, etc. The content of the active constituent in the above- mentioned formulations is 0.1-99.9wt%, preferably 1-99wt% expressed in terms of weight ratio.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a rice blast control agent which is important as an agricultural fungicide.

[Conventional technology]

Rice blast is one of the important plant diseases in rice cultivation.
Various preventive and therapeutic agents have been developed for rice blast disease.

Examples of long-chain unsaturated carboxylic acid derivatives similar to the compounds of the present invention as control agents for rice blast disease include octadecatrienecarboxylic acid oxides (Japanese Patent Application Laid-Open No. 59-148706).
is disclosed.

However, the disclosed compounds are extracted from natural products, and it is difficult to practically use them as agricultural fungicides.

[Problem that the invention seeks to solve]

Many naturally occurring antibacterial active substances are known, but their production is not easy. Therefore, despite their usefulness, only a few of the natural antibacterial active substances are actually used.

[Means for solving problems]

The present inventors have completed the present invention as a result of extensive research into substances that have a structure similar to naturally occurring antibacterial active substances, have the same antibacterial activity, and can be chemically synthesized. That is, the present invention provides general formula (I) n-Cs )-111C==CCH=CHCH(CH
z) 9-hydroxyoctadec-10-ene-1 represented by 7HCOOCH3(I)
The present invention provides a rice blast control agent containing 2-ynecarboxylic acid methyl ester (hereinafter referred to as the compound of the present invention) as an active ingredient. The present invention will be explained in detail below.

[Effect]

The compound of the present invention has optical isomers due to the asymmetric carbon at the 9-position and geometric isomers due to the double bond at the 10-position, but the present invention includes all stereoisomers. included.

The compounds of the present invention include, for example, H, B, S, konaracar, F,
D, the method of Gunston et al. (Livid, Vol. 5, No. 1, pp. 137-141, 1970), the method of St. Antrius et al. (Chemical Communication, No. 6, p. 281-)
282 p. 1968), the method of Patrick et al.
p.-646, 1979).

A control agent containing the compound of the present invention as an active ingredient is useful against rice blast, especially leaf blast, which occurs in paddy fields, while virtually no chemical damage to rice is observed.

When the compound of the present invention is used as a rice blast control agent, it may be used as it is without adding other ingredients, but it is usually mixed with a solid carrier, liquid carrier, surfactant, or other formulation auxiliary to form an emulsion or water. Formulate into Japanese preparations, suspensions, granules, etc.

These preparations contain the compound of the present invention as an active ingredient in a weight ratio of 0.1 to 99.9%, preferably 1 to 99%.

Solid carriers include fine powders or granules such as kaolin clay, attabulgite clay, bentonite, acid clay, pyrophyllite, talc, diatomaceous earth, calcite, corn cob flour, walnut flour, urea, ammonium sulfate, and synthetic hydrous silicon oxide. Liquid carriers include xylene,
Examples include alcohols such as isopropanol, ethylene glycol, and cellosolve, ketones such as acetone, cyclohexanone, and isophorone, vegetable oils such as soybean oil and cottonseed oil, dimethyl sulfoxide, acetonitrile, and water.

Surfactants used for emulsification, dispersion, wet layer, etc. include alkyl (aryl) sulfonates, dialkyl sulfosuccinates, polyoxyethylene alkylaryl ether phosphate ester salts, alkyl sulfate ester salts, naphthalene sulfonic acid Examples include anionic surfactants such as formalin condensates, nonionic surfactants such as polyoxyethylene alkyl ether, polyoxyethylene, polyoxybrobylene block copolymer, and sorbitan fatty acid ester. Formulation aids include lignin sulfonate, alginate, polyvinyl alcohol, gum arabic, CM
Examples include C (carboxymethyl cellulose) and P'AP (isopropyl acid phosphate).

Furthermore, the compound of the present invention can be mixed with fungicides such as thiuram, dithianonbattamycin A1 polyoxin, and cerocidin, and insecticides such as Marathon, Sumithion, NAC, and BPMC, herbicides, fertilizer components, etc., and applied as a fungicide to agricultural crops. It is also possible to expand the range, or to exhibit insecticidal, herbicidal, or fertilizing effects at the same time.

〔Example〕

Hereinafter, the present invention will be explained in more detail with reference to Examples. In the examples, "part" means parts by weight.

Example 1 Preparation 95 parts of a solution consisting of 5 parts of cyclohexanone and 1 part of toxanone P-8L (trade name of emulsifier manufactured by Sanyo Kasei Co., Ltd.) and 5 parts of the compound of the present invention were weighed and mixed uniformly to obtain a base agent content of 5 parts. % emulsion was obtained.

Example 2 Preventive effect test against rice blast A cup was placed and 50 Id of a 100-fold diluted solution of the emulsion prepared in Example 1 was sprayed by hand spray.

After air-drying the chemical solution, place it in a greenhouse set at a temperature of 25℃, and heat it to about 20α.
Rice blast disease infected straw (P 1riculariaor)
yzae) was installed and left undisturbed for 4 days.

For each cup, calculate the proportion of main lesions on the 3rd and 4th true leaves to each leaf area, using the method below to calculate 10 stems (2
0 stems), and the disease severity and control value were determined according to formulas (1) and (2).

Disease index Disease area rate Note) 0...0% 1...Less than 10%2...10% or more but less than 25%3...
・・・・・・25% or more but less than 50%4 ・・・・・・
50% or moreNote) Infection area of this lesion in the surveyed leaf area - (ΣIncidence index x number of applicable leaves)/(4X number of surveyed leaves)
X100 Equation (1) Control value = [(Incidence level in untreated area - Incidence intensity in each treated area) / Infectivity level in untreated area x 100 Equation (2) The results are shown in Table 1.

Table 1 (Effects of the Invention) As is clear from the above description, the compound of the present invention exhibits a high controlling effect on rice blast, and is useful as a rice blast controlling agent.

Claims (1)

[Claims] 1) 9-hydroxyoctadec-10-ene-1 represented by the general formula (I) ▲There are numerical formulas, chemical formulas, tables, etc.▼(I)
Rice blast control agent containing 2-ynecarboxylic acid methyl ester as an active ingredient