JPH0580443B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial application field] The present invention is based on the formula ():

[Conventional technology]

As a result of many years of research and development into herbicides, a wide variety of herbicides have been put into practical use, and these herbicides have contributed to labor-saving weed control operations and improved productivity of agricultural and horticultural crops. Even today, there is a demand for the development of new chemicals with better herbicidal properties, and in particular, as herbicides for agriculture and horticulture, they are used to selectively control only target weeds at low doses without causing harm to cultivated crops. However, existing drugs do not necessarily meet this requirement. The compound represented by formula () exhibits superior herbicidal effects at lower doses than conventional herbicides, and is highly safe for rice. Furthermore, it is highly effective not only against annual grass weeds and annual broad-leaved weeds, but also against perennial weeds, making it highly useful. On the other hand, bromobutide is a useful herbicide that is highly effective against Cyperaceae, such as bulrushes, and at the same time exhibits excellent effects against grasshoppers, grasshoppers, and the like. However, broad-leaved weeds and perennial cyperaceous weeds that arise from tubers, such as Cyperus cyperus,
It is difficult to expect a complete effect on black guinea pigs, and improvements are desired. [Aspects of the Invention] As a result of research to increase the herbicidal effect of the compound represented by formula (), the present inventor found that when bromobutide is added to the compound represented by formula (), the respective herbicidal effects are increased. This is an excellent mixture that not only has an additive but also a synergistic herbicidal effect, and has much higher crop safety and herbicidal effect against noxious weeds than previously known mixtures. The present invention was completed by discovering that the present invention can be used as a drug. As a result, there is no chemical damage to rice,
The usefulness of the present invention is extremely high since it is possible to control a wide range of weeds with a low dosage. In addition, the herbicide composition of the present invention is effective even when treated before and after weed germination, and is effective in soil treatment,
High effects can be obtained by treating the leaves and soil as well. It is also useful for various grains other than rice, and can also be used to control various weeds in agricultural and horticultural fields such as fields and orchards, as well as in non-agricultural areas such as playgrounds, vacant lots, forest areas, tank yards, and railway edges. It can be applied and shows great economic effects in weed control. The composition according to the invention generally contains 0.001 to 10 parts by weight of the compound represented by formula () per part by weight of bromobutide, depending on the relative activities of each component. The amount of mixture to be applied will depend on a number of factors, such as the specific target plant species to be inhibited, but is generally between 0.001 and 1.
A quantity of Kg/ha is usually appropriate. When the composition of the present invention is used as a herbicide, it is usually mixed with a solid carrier, a liquid carrier, a surfactant, and other formulation auxiliaries to formulate an emulsion, wettable powder, suspension, or the like. These preparations contain a total amount of active ingredients of 1 to 90%, preferably 2 to 80% by weight. Examples of solid carriers include fine powders or granules such as kaolin clay, attapalgite clay, bentonite, acid clay, calcium carbonate, pyrofluorite, talc, diatomaceous earth, calcite, walnut powder, urea, ammonium sulfate, and synthetic hydrous silicon oxide. Liquid carriers include aromatic hydrocarbons such as xylene and methylnaphthalene, alcohols such as isopropanol, ethylene glycol, and cellosolve, ketones such as acetone cyclohexanone and isophorone, vegetable oils such as soybean oil and cottonseed oil, and dimethyl sulfoxide. , acetonitrile, water, etc. Surfactants used for emulsification, dispersion, wetting, etc. include anionic surfactants such as alkyl sulfates, alkylaryl sulfonates, dialkyl sulfosuccinates, and polyoxyethylene alkylaryl ether phosphate ester salts. , polyoxyethylene alkyl ether, polyoxyethylene polyoxypropylene block copolymer, sorbitan fatty acid ester, and other nonionic surfactants. Other formulation adjuvants include lignin sulfonate, alginate,
Examples include polyvinyl alcohol, gum arabic, CMC (carboxymethyl cellulose), and PAP (isopropyl acid phosphate). The herbicidal composition of the present invention can also be blended with other herbicides in order to obtain better herbicidal effects. Examples of such herbicides include 2,4,6-trichlorophenyl-4'-nitrophenyl ether, 2,4-dichlorophenyl-
3'-methoxycarbonyl-4'-nitrophenyl ether, 2,4-dichlorophenyl-3'-methoxy-4'-nitrophenyl ether, S-(4-chlorobenzyl)-N,N-diethyl Thiol carbamate, S-ethyl-N,N-hexamethylenethiol carbamate, S-benzyl-N-(1,
2-dimethylpropyl)-N-ethyl-thiol carbamate, S-(1-methyl-1-phenylethyl)-piperidine-1-carbothioate,
2-Chloro-2'6'-diethyl-N-(butoxymethyl)acetanilide, 2-chloro-2'6'-diethyl-N-(2-propoxyethyl)acetanilide, N-[2'-(3'- methoxy)-thienylmethyl]-N-chloroacet-2,6-dimethylanilide, 2',3'-dichloro-4-ethoxymethoxybenzanilide, 2-benzothiazol-2-yloxy-N-methylacetanilide, 3, 7-
Dichloro-8-quinolinecarboxylic acid, 0-(3-
tert-butylphenyl)-N-(6-methoxy-2
-pyridyl)-N-methylthiocarbamate, 3
-(2,4-dichloro-5-isopropoxyphenyl)-5-tert-butyl-1,3,4-oxadiazol-2(3H)-one and the like.
Individual active compounds often exhibit drawbacks in their herbicidal activity, but in such cases, the herbicidal activity of a combination of two active compounds is simply the sum of the respective activities of the two compounds ( When the activity is greater than the expected activity, this is called synergism. The expected activity of a particular combination of two herbicides can be calculated as follows.
(See Colby SR Calculation of synergistic and antagonistic reactions of herbicide combinations, "Weed," Vol. 15, pp. 20-22, 1967) E = α + β - α · β / 100 α: Amount of herbicide A in a kg/ha Inhibition rate β when treated with herbicide B: Inhibition rate E when treated with herbicide B at an amount of bKg/ha: herbicide A at aKg/ha, herbicide B at bKg/ha
In other words, if the actual inhibition rate is greater than the above calculation, it can be said that the combined activity exhibits a synergistic effect. Hereinafter, the present invention will be explained in more detail with reference to Examples, but the compounds, dosage amounts, dosage forms, etc. in the present invention are not limited to the Examples. In addition, all "parts" mean parts by weight. Formulation example 1 Granule compound ()...0.07 parts Bromobutide...3 parts Bentonite...20 parts Talc...76.93 parts After uniformly mixing and pulverizing the above, add a small amount of water, stir, mix, and extrude. Granulate it with a granulator and dry it to make granules. Formulation example 2 Granule compound ()...0.05 parts Bromobutide...5 parts Bentonite...20 parts Talc...74.95 parts After uniformly mixing and pulverizing the above, a small amount of water is added, stirring and kneading are carried out, followed by extrusion manufacturing. Granulate it with a granulator and dry it to make granules. Formulation example 3 Flowable agent compound ()...0.4 parts Bromobutide...2.5 parts Agrisol S-710...10 parts (nonionic surfactant: Kao Atlas Co., Ltd. trade name) Lunotx 1000C...0.5 parts (anionic Surfactant: Toho Chemical Co., Ltd. trade name) 1% Rhodopol water...20 parts (Thickener: Lone Poulenc trade name) Ethylene glycol...10 parts Water...56.6 parts The raw material was finely ground and the above Mix uniformly with other ingredients to make a flowable agent. Formulation example 4 Emulsion compound ()...0.5 parts Bromobutide...6 parts Xylene...72.5 parts Dimethylformamide...15 parts Soybean oil...1 part Solpol 2680...5 parts (nonionic surfactant and anionic interface) Mixture with activator: Toho Chemical Co., Ltd. (trade name) The above is mixed uniformly to form an emulsion. Formulation example 5 Wettable powder compound ()...2 parts Bromobutide...24 parts Siegrite A...64 parts (kaolin clay: trade name of Sieglite Industries Co., Ltd.) Solpol 5039...2 parts (alkyl ether sulfate) : Toho Chemical Co., Ltd. trade name) Solpol 5050...2 parts (Dioctylsulfosuccinate diluted with 50% white carbon: Toho Chemical Co., Ltd. trade name) Soybean oil...2 parts Carplex (anti-caking agent)... ...4 parts (white carbon: trade name of Shionogi & Co., Ltd.) The above is mixed and pulverized uniformly to make a wettable powder. Test Example 1 Weeding effect test under flooded conditions After putting alluvial soil in a 1/5000 are Wagner pot, water is added and mixed to create a flooded condition with a water depth of 4 cm. Seeds of Japanese millet, broad-leaved weeds (Japanese violacea, azalea, azalea, and bulrushes),
The seeds were mixedly sown in the above pots, and tubers of Urikawa and Cyperus japonica were also placed on the bed. Furthermore, rice seedlings at the 2.5 leaf stage were transplanted. Plants are grown in pots in a greenhouse at 25 to 30°C, and 10 days after sowing, red millet grows.
1.5 At the leaf stage, the prescribed amount of medicine is applied to the water surface.
The diluted drug solution was added dropwise using a measuring pipette. Three weeks after dropping the chemical solution, the herbicidal effect on various weeds was investigated according to the following criteria. Table 1 shows the results of the herbicidal effect test for a single agent, and Table 2 shows the results of the herbicidal effect test for a mixture of the two agents. Judgment criteria 5... Weed killing rate 90% or more (almost complete death) 4... Weed killing rate 70-89% 3... Weed killing rate 40-69% 2... Weed killing rate 20-39% 1... Weed killing rate 5-19 % 0...Weed killing rate 5% or less (almost no effect)

【table】

[Table] Test Example 2 Synergistic effect test against Cyperus japonica A 1/10,000 are Neubauer pot was filled with paddy soil to form a paddy field, and the tubers of cypress cypress that had germinated were planted. On the third day after planting, 1 ml of a diluted drug solution of a predetermined concentration was dropped into the water using a volumetric pipette. After growing in a greenhouse for 30 days, the weight of the above-ground parts of Cypera spp. was measured, and the inhibition rate was determined using the method described below. Weed killing rate (%) = (1 - aboveground grass weight in treated area /
Table 3 shows the test results for a single agent, and Table 4 shows the test results for a mixture of the two agents.

【table】

【table】

[Table] In the table, the expected value shows the calculated value obtained from Colby's formula in the previous period. As described above, the inhibition rate of above-ground body weight exceeded the expected value. The synergistic effect of the composition of the present invention is also clearly demonstrated by analysis using the isoeffect line method. In other words, by determining several compositions with different mixing ratios of herbicide A and herbicide B that exhibit a growth inhibition rate of 90%, and plotting these as shown in Figure 1, it is possible to determine the synergistic and additive effects. , the antagonistic effects can be easily analyzed [Junichi Fukami, Yasuhiko Uesugi, Akizo Ishizuka, Chojiro Tomizawa (eds.) Pesticide Experimental Methods Vol. 8 Herbicides Edition 1st Edition No. 109
- p. 111 (1981) published by Soft Science Publishing]. In other words, if the isoeffect line is below the additive effect line, it indicates a synergistic effect. As shown in FIG. 1, the isoeffect line for the composition of the present invention is below the additive effect line, clearly indicating a true synergistic effect.

[Brief explanation of the drawing]

Figure 1 is a plot of the drug dose required for 90% inhibition based on the herbicidal activity against Cyperus spp. shown in Tables 3 and 4 using the iso-effect line method. The vertical axis is the dose of bromobutide (g/a), and the horizontal axis is the compound ()
The drug amount (g/a) is shown. The broken line shows the line for an additive effect, and the solid line shows the isoeffect line for the actually measured stunting rate of 90%.

Claims (1)

[Claims] 1 Formula (): Pyrazolesulfonylurea represented by [Formula] and N-
1. A herbicidal composition comprising (α,α-dimethylbenzyl)-α-bromotarsiallybutylacetamide as an active ingredient.