JPS6324482B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention is based on the formula 3-isopropyl-2,1,3-benzothiadiazin-4-one-2,2-dioxide (hereinafter abbreviated as compound (A)) having the formula (In the formula, Y represents a hydrogen atom, p-toluenesulfonyl group, or phenacyl group.)
This invention relates to a mixed paddy field herbicide that produces a synergistic effect that is unexpectedly significant when applied alone, and can kill a wide variety of weeds at low application rates. To explain the present invention in more detail, the compound (A), which is one of the components of this herbicide, is known as a herbicide, and is highly effective against perennial weeds such as bulrush, weed, and black grass, and is effective against rice. Highly safe. However, while the activity is strong in mid-growth treatment, the effect becomes weaker in pre-emergence soil treatment. On the other hand, pyrazole compounds are disclosed in Japanese Patent Application Laid-Open No. 50-126830.
It is known as a herbicide in Japanese Patent Application Laid-open No. 55-33454, and is effective against annual grass weeds, broad-leaved weeds, and perennial weeds such as Japanese cypress, Omodaka, and Urikawa, without causing any chemical damage to paddy rice in paddy fields. have an effect. However, if the weeds are treated with chemicals when they have grown to a certain extent, the effect will be reduced, and the effect on wild grasses will be insufficient. However, by applying both in combination, the herbicidal effect
As a result of examining drug damage, the range of herbicides was surprisingly expanded beyond the scope of application obtained with each single agent. It can be used to control perennial weeds such as Japanese cypress and paddy rice without compromising safety.
It has been found that this method has the effect of expanding the range of suitable spraying periods. In addition, this herbicide is sufficiently effective when mixed at a much lower dose than when used alone, and its herbicidal efficacy has been increased sufficiently to be used as a one-time treatment agent, and its efficacy is long-lasting. lasts for a long time. Examples of the pyrazole derivatives used as the active ingredient of the present invention include the following compounds. In addition, compound numbers are referred to in the following description. (1) 1,3-dimethyl-4-(2,4-dichlorobenzoyl)-5-hydroxypyrazole mp.165-166℃ (2) p-toluenesulfonate of (1) mp.122-124℃ (3) The p-toluenesulfonic acid ester and phenacyl ether of the compound (1) above are both converted to the compound (1) in the soil or in the plant body when used. It can be used in the same way. The mutual effect related to the present invention is observed in a wide range of mixing ratios, and the compound (A) has the general formula ()
A useful herbicide can be prepared by mixing the compounds represented by 0.1 to 10 parts by weight. The herbicide of the present invention is effective even when treated before and after the germination of weeds in paddy fields, and is highly effective when treated with soil or sprayed on foliage. The mixture of the present invention may be sprayed as a liquid itself, or may be mixed with a carrier and other adjuvants as necessary to form a drug commonly used as a herbicide.
For example, they are prepared and used as powders, coarse powders, fine granules, granules, and wettable powders. Suitable solid carriers for use in preparing the herbicide of the present invention include clays represented by the kaolinite group, montmorillonite group, or attabulgite group, talc, mica, pyrophyllite, pumice, vermiyukilite, and gypsum. , calcium carbonate, dolomite, diatomaceous earth, magnesium lime, apatite, zeolite, anhydrous silicic acid, synthetic calcium silicate and other inorganic substances, soybean flour, tobacco flour, walnut flour, wheat flour, wood flour, starch, crystalline cellulose. vegetable organic substances such as coumaron resin, petroleum resin, alkyd resin, polyvinyl chloride, polyalkylene glycol, ketone resin, synthetic or natural polymer compounds such as ester gum, copal gum, dammar gum, wax such as carnauba wax, beeswax, etc. and urea. Surfactants used for purposes such as dispersion, wetting, spreading, binding, disintegration control, stabilization of active ingredients, fluidity improvement, and rust prevention are nonionic, anionic, cationic, and zwitterionic. Although either non-ionic and/or
Anionic substances are used. Furthermore, the herbicide of the present invention includes casein, gelatin, albumin, glue, sodium alginate, carboxymethyl cellulose, methyl cellulose,
High molecular compounds such as hydroxyethyl cellulose and polyvinyl alcohol and other auxiliary agents can also be used in combination. The above-mentioned carriers and various auxiliary agents are used in the dosage form of the preparation,
They are used individually or in combination as appropriate depending on the purpose, taking into consideration the application situation. Wettable powders usually contain, for example, 25 to 90 parts by weight of the active ingredient compound, with the remainder being a solid carrier, a dispersing wetting agent, and optionally a protective colloid agent, a thixotropic agent, an antifoaming agent, and the like. Granules, for example, usually contain 1 to 35 parts by weight of the active ingredient compound, with the remainder being mostly solid carrier. The active ingredient compound is uniformly mixed with the solid carrier, or is uniformly fixed or adsorbed on the surface of the solid carrier, and the particle size is about 0.2 to
It is about 1.5mm. Examples of formulations of this herbicide are shown below. Formulation Example 1 20 parts by weight of Compound (2), 20 parts by weight of Compound (A), 2.5 parts by weight of dodecylbenzenesulfonate, 2.5 parts by weight of lignosulfonate and 55 parts by weight of diatomaceous earth were thoroughly ground and mixed to form a wettable powder. obtain. Formulation Example 2 5 parts by weight of compound (2), 3 parts by weight of compound (A), 3 parts by weight of white carbon, 5 parts by weight of lignin sulfonate, and 84 parts by weight of clay were thoroughly ground and mixed, and water was added and kneaded well. After granulation and drying, granules are obtained. Formulation Example 3 40 parts by weight of bentonite, 5 parts by weight of lignin sulfonate and 55 parts by weight of clay are pulverized and mixed, water is added, kneaded and granulated and dried to produce granules containing no active ingredient. Granules are obtained by impregnating 95 parts by weight of the granules with 1 part by weight of compound (3) and 4 parts by weight of compound (A). Next, in order to more specifically demonstrate the effect of the herbicide of the present invention, test examples will be given and explained. Test Example 1 A polyethylene pot with an inner diameter of 8 cm was filled with paddy soil, and Cyperus japonica was grown in the paddy field, and the flooded soil was treated with a prescribed amount of each drug formulated into a hydrating powder at the third leaf stage of the cypress. The pots were placed in a greenhouse at 25 to 30°C and grown under control. Thirty days after the treatment, the fresh weight of the above-ground parts of the remaining cypress was measured, and the ratio to the untreated plot was calculated. The results are shown in Table 1.

[Table] Test Example 2 A 1/5000a Wagner pot filled with 3 kg of paddy soil was filled with water to create a paddy field, and seeds of Japanese millet, bulrush, and broad-leaved weeds such as Japanese apricot, azalea, and paddy were sown in the pot. I planted the tubers of black bream. 2.5 more
Transplant the rice seedlings at the leaf stage, place the pots in a greenhouse at 20-25°C to grow the plants, and on the 7th day after sowing, one barnyard millet grows.
At the leaf stage, a predetermined amount of the drug was formulated into a wettable powder, diluted with water, and treated at 10 c.c. per pot. The plants were then grown in a greenhouse, and the herbicidal effect was investigated 25 days after the chemical treatment. The herbicidal effect was expressed as a number from 0 to 10 as shown below based on the observation of the weed suppression rate, degree of whitening, etc. The results are shown in Table 2. Weed suppression rate 0:0-9% 6:60-69 1:10-19 7:70-79 2:20-29 8:80-89 3:30-39 9:90-99 4:40-49 10 :100 (completely dead) 5:50-59

【table】

Claims (1)

[Claims] 1 3-isopropyl-2,1,3-benzothiadiazin-4-one-2,2-dioxide, and the formula (In the formula, Y represents a hydrogen atom, a p-toluenesulfonyl group, or a phenacyl group.) A pyrazole derivative represented by: