JPS6332047B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to S-(2-methyl-1,1-piperidyl-carbonylmethyl)-O,O-di-n-propyldithiophosphate (hereinafter abbreviated as compound A) and 2-methylthio-4-ethylamino -6
-Relating to a herbicide composition for rice fields containing (1,2-dimethylpropylamino)-s-triazine (hereinafter abbreviated as compound B) and ethyl 2-methyl-4-chlorophenoxybutyrate (hereinafter abbreviated as compound C) . In recent years, with the widespread use of herbicides for paddy fields, the main paddy weeds that were previously targeted for weed control, such as annual grass weeds such as Japanese millet, annual broad-leaved weeds such as Japanese grasshopper, and perennial weeds, include Japanese grasshopper. The weeds were removed to a satisfactory level. However, for this reason, perennial weeds other than the above-mentioned weeds have been suppressed by these major weeds, and their occurrence is localized or in small quantities and does not pose a major hindrance to wet rice cultivation. Coupled with the fact that herbicides for paddy fields are not sufficient to control it, it has begun to show universal occurrence and growth, and has become a new problem in controlling weeds in paddy fields. Needless to say, there is a strong demand for the development of a herbicide for paddy fields that can also exterminate perennial weeds other than the new problem of grasshopper. On the other hand, compound A and compound B, which are part of the active ingredients in the present invention, are mixed in an appropriate ratio to form a preparation suitable for application to paddy fields, and the preparation is applied alone to paddy fields after transplanting paddy rice, or By applying a herbicide called an initial herbicide that is applied before and after transplanting, it can be used to control barnyard grasses, grasshoppers, and grasshoppers.
It can control annual weeds in paddy fields such as azalea, horsetail, and cyperus, as well as perennial weeds such as pine weeds, staghorn grass, cyperus, and young bulrushes and cyperus japonica. However, this combination is insufficiently effective against urikawa. As a result of various studies, the present inventors have found that when compound A, compound B, and compound C are combined, the herbicidal spectrum of the mixed herbicide of compound A and compound B and the degree of efficacy against each grass species are reduced. It was discovered that the mixture of Compound A and Compound B exhibited a remarkable herbicidal effect that could not be expected from the effect of the mixture of Compound A and Compound B on Prunus elegans and the effect of Compound C alone on Prunus elegans, and that it did not impair safety on paddy rice. , based on this, the present invention was completed. The herbicide composition for paddy fields of the present invention can be prepared by dissolving or dispersing Compound A, Compound B, and Compound C in a suitable liquid carrier (e.g., a solvent), or by dissolving or dispersing them in a suitable solid carrier (e.g., a diluent, a filler). By mixing with or adsorbing on this, emulsifiers, dispersants, suspending agents, wetting agents, stabilizers, etc. are added to create emulsions, wetting agents, suspending agents, granules, fine granules, etc. It may be used in an appropriate dosage form. In particular, it is convenient to use it as a granule. Next, such solvents include, for example, aliphatic hydrocarbons (for example, gasoline, kerosene, kerosene, fuel oil, machine oil, etc.), aromatic hydrocarbons (for example, benzene, toluene, xylene, solvent, naphtha, methyl (e.g. naphthalene), halogenated hydrocarbons (e.g. chloroform,
Carbon tetrachloride, etc.), esters (eg, ethyl acetate, butyl acetate, glycerin ester of fatty acids, etc.), sulfur-containing compounds (eg, dimethyl sulfoxide, tetramethylene sulfone, etc.), and the like can be used. In addition, solid carriers such as diluents and fillers include mineral powders (for example, kaolin,
Bentonite, calcium phosphate, clays such as acid clay, talcs such as waxite powder, diatomaceous earth,
Silicas such as mica powder, etc.) are also used, and these may be used alone or in a mixture of two or more. In addition, as emulsifiers, penetrants, dispersants, etc., for example, soaps, sulfuric esters of higher alcohols, alkyl sulfonic acids, alkylaryl sulfonic acids, quaternary ammonium salts, oxyalkylamines, fatty acid esters, polyalkylene oxide interfaces, etc. Active agents and the like are widely used, and it is generally preferable to include them in the formulation in an amount of about 0.2 to 10%. Further, if necessary, for example, CMC, polyvinyl alcohol, bentonite, cresol soap, etc. may be contained. Further, other types of herbicides, plant growth regulators, plant nutrients, fertilizers, etc. may be mixed as appropriate. The blending ratio (weight ratio) of the active ingredients Compound A, Compound B, and Compound C in the herbicide composition for paddy fields of the present invention is generally 1 to 10:0.1 to 5:0.1 to 5, preferably 3 to 6: 0.5-2: 0.5-1.5. In addition, the total proportion of these compounds A, B, and C in the composition of the present invention is about 10 to 90% (w/w) in emulsions, wettable powders, etc.
In addition, for oils, powders, etc., it is appropriate to use about 0.1 to 10% (w/w), and for granules, it is appropriate to use 1 to 30% (w/w), preferably about 3 to 10% (w/w). . Note that emulsions, hydrating agents, and the like are preferably further diluted (for example, 50 to 500 times) with water and the like before being sprayed. The amount of the active ingredient used, the combination with other types of chemicals, and the ratio of these ingredients will vary depending on various conditions such as the growth stage of the target paddy field weeds and paddy rice, growth conditions, and the time and method of application of the chemicals. Compound A, which is generally the active ingredient,
The total amount of B and C may be adjusted to about 50 to 500 g, preferably about 150 to 250 g, per 10 ares. In addition, the present invention is not limited to any method of use as long as it is safe for paddy crops and effective against paddy field weeds. The herbicidal composition for paddy fields of the present invention has very little phytotoxicity, and can easily, inexpensively, and accurately exert excellent herbicidal action against a wide range of paddy field weeds, and therefore is extremely useful in the art. Next, some examples will be shown, but the present invention is not limited to the following. In the examples, all "parts" mean parts by weight. Example 1 Granules 3 parts of Compound A, 1 part of Compound B, 0.8 parts of Compound C, 1 part of sodium dodecylbenzenesulfonate, 2.2 parts of polyoxyethylene alkylaryl ether, and 92 parts of clay were mixed, water was added, and the mixture was kneaded. , obtain 100 parts of granules using a granulator. Example 2 Granules 4.4 parts of compound A, 1.1 parts of compound B, 1 part of compound C,
2 parts of sodium alkylbenzene sulfonate, 0.5 parts of polyvinyl alcohol, 45 parts of talc, and 46 parts of clay are mixed, an appropriate amount of water is added and kneaded, and 100 parts of granules are obtained using a granulator. Example 3 Emulsion 20 parts of compound A, 5 parts of compound B, 4 parts of compound C,
56 parts of xylene and 15 parts of polyoxyethylene nonyl phenyl ether are uniformly mixed to obtain 100 parts of an emulsion. Example 4 Wettable powder 40 parts of compound A, 10 parts of compound B, 10 parts of compound C,
Mix and grind 10 parts of white carbon, 27 parts of diatomaceous earth, and 3 parts of sodium ligninsulfonate to make a 100% wettable powder.
get the part. The herbicidal effect and safety of the composition of the present invention on paddy rice will be explained below using test examples. Test Example 1 Efficacy test on Urikawa and phytotoxicity test on paddy rice On a stand with a transparent plastic roof,
Place 1/5000 are Wagner pots, fill the paddy soil (sandy loam), add water, and plow, then plant 7 sprouting tubers of Urikawa per pot, and 3 paddy rice seedlings (variety: Nipponbare) in another pot. As one plant, 3 plants were transplanted per pot, and each pot was cultivated in a flooded state.
When the leaves and paddy rice reached 5.1 leaves in leaf age, the chemicals prepared in accordance with Example 1 were added to each pot as shown in Table 1.
The particles were uniformly powdered so that the amount of active ingredient applied (g/a) shown in Table 2 was obtained. On the 28th day after each chemical treatment, the plants of Urikawa were removed, the above-ground parts were cut off, and the plants were incubated at 70℃ for 72 days.
After drying for several hours, the weight (dry weight) was measured, and the residual rate was calculated using the following formula, which was used as an indicator of effectiveness.
Regarding paddy rice, the plant height and number of stems were measured on the 28th day after treatment, and the above-ground parts were harvested and dried in the same manner, and their weight was measured. The test was repeated three times. The test results are shown in Tables 1 and 2. Survival rate (%) = Dry weight of treated area / Dry weight of untreated area x 10
0

[Table] As shown in the above table, the effect of the composition of the present application on urikawa is significantly higher than that of the control group using the active ingredient.

[Table] From the results in the above table, it can be seen that even if Compound C is added to a mixed composition of Compound A and Compound B at a practical dose, the safety for paddy rice is not impaired. Test example 2 Effect on Japanese millet (greenhouse test) Fill a 1/5000 Earl Wagner pot with paddy soil (sandy loam) in a greenhouse, and after watering and puddling, 15 germinated seeds of Japanese millet were sown per pot, and the water depth was 3.
The plants were cultivated under waterlogging conditions of 1 cm. When the leaf age of Japanese millet reached 1.5 leaves, 2.0 leaves, and 2.5 leaves, 10 plants with uniform growth were left and the others were removed, and the test chemicals prepared according to Example 1 were applied to each effective drug shown in Table 3. The particles were uniformly dispersed to match the application amount (g/a) of the ingredients. The test was conducted three times per treatment. Four weeks after the chemical treatment, the above-ground parts of the Japanese grasshopper were harvested, dried at 70°C for 72 hours, weighed, and the survival rate was calculated using the same formula as in Test Example 1, which was used as an indicator of effectiveness. The test results are shown in Table 3.

[Table] From the results in the above table, it is understood that even if Compound C is added to the combination of Compound A and Compound B, there is no change in the effect on Japanese millet. Test Example 3 Field Test 1 A paddy field made of alluvial clay loam where annual and perennial weeds naturally coexist was tilled.
A test plot of m ² was created, and paddy rice (variety: Nipponbare) with 2.9 leaves was transplanted on June 11th, and 10 days after transplantation and
After 15 days, the granules prepared according to Example 1 were uniformly dispersed in each test area so that the application amount (g/a) of each active ingredient shown in Table 4 was obtained, and thereafter they were managed in the usual manner. did. On the 46th day after rice transplantation, two 0.5 m ² study plots were set up for each test, all weeds growing there were removed, and the number of individuals and dry weight of each weed was measured. On the other hand, 21 days after the chemical treatment, the paddy rice was observed for phytotoxicity, and the "degree of phytotoxicity" was determined as described in the Japan Plant Regulator Research Association's "Herbicide Testing Standards" (October 1975), page 42. They were distinguished accordingly. Regarding the effect on weeds, the survival rate was calculated using the following formula and used as an indicator of effectiveness. The results are shown in Table 4. Survival rate (%) = Dry weight of treated area / Dry weight of untreated area x 100

[Table] Field test 2 A paddy field made of alluvial clay soil in which annual and perennial weeds naturally coexist was tilled.
On the 20th of May, I flooded the rice field, plowed it, and created a test plot of 8 m ² in one section. The next day, 300 g of Xgorny Granules (manufactured by Ishihara Sangyo; containing 7% of the active ingredient 2,4-dichlorophenyl-3'-methoxy-4'-nitrophenyl ether), which is said to be an early paddy herbicide, was applied to all test plots.
The mixture was uniformly sprayed at a ratio of g/a, and paddy rice seedlings were transplanted two days later on June 23rd. On the 15th and 20th day after transplantation, the granules prepared according to Example 1 were uniformly scattered in each test plot so that the application amount (g/a) of each active ingredient was shown in Table 5. Thereafter, it was managed using normal methods. On August 3rd ^, two study plots of 0.5 m ² per test plot were established, and if weeds were growing in the plots, they were removed, dried indoors for 5 days, and weighed. . On the other hand, on July 30th, the plant height, number of stems, and "degree of chemical damage" of 20 rice plants per test plot were measured in the same manner as in Test Example 3. The results of the test are shown in Table 5.

[Table] As is clear from Tables 4 and 5,
The mixed composition according to the invention exhibits a high practical effect on cucumbers even under field conditions. At the same time, it can be seen that the effects on other weeds are extremely high, and the chemical damage to paddy rice is small or non-existent.

Claims (1)

[Claims] 1 S-(2-methyl-1,1-piperidyl-carbonylmethyl)-O,O-di-n-propyldithiophosphate and 2-methylthio-4-ethylamino-6-(1,2-dimethylpropylamino )
A herbicide composition for rice fields, comprising -s-triazine and ethyl 2-methyl-4-chlorophenoxybutyrate as active ingredients.