JPH0511089B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention is based on the general formula (): [In the formula, A represents lower alkyl. B represents a halogen atom or a lower alkoxy group. R represents a lower alkyl group. Z represents a nitrogen atom or a CH group. X and Y each independently represent a lower alkyl group or a lower alkoxy group. ] A pyrazolesulfonylurea derivative represented by The present invention relates to a herbicide characterized by containing oxadiazone (referred to as oxadiazone) as an active ingredient. 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 drugs with better herbicide properties, and in particular, as herbicides for agricultural and horticultural use, they can selectively target only target weeds at low doses without causing harm to cultivated crops. Although it is desirable to be able to control the disease, existing drugs do not necessarily meet this requirement. Compounds represented by the general formula () exhibit superior herbicidal effects at lower dosages than conventional herbicides, and are highly safe for rice. In addition, it is not only highly effective against annual grass weeds and annual broad-leaved weeds, but also highly effective against perennial weeds, and its useful life is great. In addition, oxadiazone, which has been known in the past, has been used in higher dosages than the compound represented by the general formula () against wild grasses, annual weeds, and fireflies, but as a result, it is difficult to control them with these agents. This has led to an increase in perennial weeds, and improvement is desired. The present inventor conducted research to increase the herbicidal effect of the compound represented by the general formula (), and found that when the compound represented by the general formula () is combined with the conventionally known herbicide, , each herbicide effect is not only obtained additively, but also
They discovered that a synergistic herbicidal effect appears and completed the present invention. This synergistic effect is great, and the composition of the present invention can completely control all types of weeds, from annual weeds to perennial weeds, with a low dosage without causing any phytotoxicity to rice, and the usefulness of the present invention is extremely large. Furthermore, the synergistic herbicidal effect particularly on barnyard grass is remarkable, and by the above-mentioned mixed application, it is also possible to reduce the amount of oxadiazone contained in the composition of the present invention, which is extremely useful. 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 economical effects in controlling weeds. The composition according to the present invention generally contains 0.001 to 50 parts by weight, preferably 0.001 to 10 parts by weight of the compound represented by the general formula () per 1 part by weight of oxadiazone, although it depends on the relative activity of each component. There is. In many cases, the greatest advantage of the combined herbicides of the invention is when the proportion of the compound of formula () is relatively lower than that of oxadiazone, e.g. Compound 0.001
Obtained at ~0.1 part by weight. The amount of mixture to be applied will depend on a number of factors, such as the type of particular target plant whose growth is to be inhibited, but generally amounts of 0.001 to 10 Kg/ha are usually adequate. Those skilled in the art can readily determine appropriate usage rates by routine, standardized tests without the need for extensive experimentation. The compositions of the invention are preferably used in the form of a composition in which the active ingredient is mixed with a carrier consisting of a solid or liquid diluent. Preferably, the composition further comprises a surfactant. Next, Table 1 shows representative examples of compounds represented by the general formula () in the present invention. Although the following compounds are included in the compounds represented by the general formula (), the compounds represented by the general formula () are not limited to these.

[Table] 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 same as the activity of each of the two compounds. When the total 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. (Calculation of synergistic and resistance reactions of combinations of colby SR herbicides, see "Weed", Vol. 15, pp. 20-22, 1967) E = α + β - α · β / 100 α: Amount of herbicide A in aKg/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 No. 1 ...0.2 parts Oxadiazone ...1.0 parts Bentonite ...50 parts Talc ...48.8 parts After uniformly mixing and pulverizing the above, add a small amount of water, stir, mix, and extrude. Granulate with a type granulator and dry to make granules. Formulation example 2 Granule Compound No. 2 ...0.1 part Oxadiazone ...0.7 part Bentonite ...40 parts Talc ...59.2 parts After uniformly mixing and pulverizing the above, add a small amount of water, stir, mix, and extrude. Granulate with a type granulator and dry to make granules. Formulation example 3 Wettable powder compound No. 3 ... 3 parts Oxadiazone ... 50 parts Siegrite A (kaolin clay: brand name of Siegrite Industries Co., Ltd.) ... 43 parts Solpol 5039 (surfactant: Toho Chemical ( Co., Ltd. product name)
...2 parts Carplex (anti-caking agent) (white carbon: trade name of Shionogi & Co., Ltd.) ...2 parts (white carbon: trade name of Shionogi & Co., Ltd.) Mix and grind the above uniformly and add water. It is used as a Japanese medicine. Formulation example 4 Granule Compound No. 4 ... 0.2 parts oxadiazone ... 1.0 parts bentonite ... 50 parts talc ... 48.8 parts or more are uniformly mixed and ground, then a small amount of water is added, stirred and kneaded, and extruded. Granulate with a type granulator and dry to make granules. Formulation example 5 Granule Compound No. 5 ...0.1 part Oxadiazone ...0.7 part Bentonite ...40 parts Talc ...59.2 parts After uniformly mixing and pulverizing the above, add a small amount of water, stir, mix, and extrude. Granulate with a type granulator and dry to make granules. Formulation example 6 Wettable powder compound No. 6 ...3 parts Oxadiazone ...50 parts Siegrite A (kaolin clay: brand name of Zeeklite Industries Co., Ltd.) ...43 parts Solpol 5039 (surfactant: Toho Scientific Co., Ltd.) Co., Ltd. product name)
...2 parts Carplex (anti-caking agent) (white carbon: brand name of Shionogi & Co., Ltd.) ...2 parts The above are mixed and ground uniformly to make a wettable powder. Formulation example 7 Granule Compound No. 7 ...0.2 parts Oxadiazone ...1.0 parts Bentonite ...50 parts Talc ...48.8 parts The above are mixed and ground evenly, then a small amount of water is added, stirred and kneaded, and extruded. Granulate with a type granulator and dry to make granules. Formulation example 8 Granule Compound No. 8 ...0.1 part Oxadiazone ...0.7 part Bentonite ...40 parts Talc ...59.2 parts After uniformly mixing and pulverizing the above, add a small amount of water, stir, mix, and extrude. Granulate with a type granulator and dry to make granules. Formulation example 9 Wettable powder compound No. 9 ... 3 parts Oxadiazone ... 50 parts Siegrite A (kaolin clay: brand name of Sieglite Industries Co., Ltd.) ... 43 parts Solpol 5039 (surfactant: Toyo Chemical Co., Ltd.) Co., Ltd. product name)
...2 parts Carplex (anti-caking agent) (white carbon: brand name of Shionogi & Co., Ltd.) ...2 parts The above are mixed and ground uniformly to make a wettable powder. Formulation example 10 Flowable compound No. 2 ... 5 parts Oxadiazone ... 25 parts Agrisol B-710 (nonionic surfactant: Kao Atlas Co., Ltd. trade name) ... 5 parts Lunox 1000C (anionic surfactant: Toho Chemical Co., Ltd. (trade name)...0.5 parts 1% Rhodopol water (thickener: Lone Prahran trade name)...20 parts water...44.5 parts Mix the above evenly to make a flowable agent. Formulation example 11 Flowable compound No. 4 ... 5 parts Oxadiazone ... 20 parts Agrisol B-710 (nonionic surfactant: Kao Atlas Co., Ltd. trade name) ... 10 parts Lunox 1000C (anionic surfactant: Toho Chemical Co., Ltd. (trade name)...0.5 parts 1% Rhodopol water (thickener: Lone Prahran trade name)...20 parts water...44.5 parts Mix the above evenly to make a flowable agent. Test Example 1 Weeding effect test under flooded conditions After placing alluvial soil in a 1/5000 are Wagner pot, add water and mix to create a freshwater condition with a water depth of 2 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, Mizugaya cypress, and Kurogwai were also placed in beds. moreover
Rice seedlings at the 2.5 leaf stage were transplanted. Pot at 25-30℃
Grow plants within a temperature range of 10 days after sowing,
When the Japanese millet was at the 1.5-leaf stage, a diluted solution of the drug was dropped onto the water surface using a volumetric pipette in a predetermined amount. Three weeks after dropping the chemical solution, the herbicidal effect on various weeds was investigated according to the following criteria. The results are shown in Tables 2 and 3. 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) However, the above weed killing rate is calculated using the following formula by measuring the above-ground grass weight in the chemical-treated area and the above-ground grass weight in the untreated area. It is something that Weed killing rate = (1 - above-ground grass weight in treated area / above-ground grass weight in non-treated area) x 100

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【table】

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[Table] Test Example 2 Synergistic effect test on barnyard millet A polyethylene pot with an inner diameter of 8 cm was filled with paddy soil, and Japanese millet was grown in the paddy field, and at the third leaf stage of barnyard millet, each prescribed drug formulated into granules was submerged in water. Soil treated. The pots were kept at a temperature of 25 to 30 degrees Celsius for controlled cultivation, and 30 days after treatment, the weight of the remaining above-ground grass of barnyard grass and the weight of above-ground grass in the untreated area was measured to determine the weed killing rate. It was calculated and judged according to the following criteria. The results are shown in Tables 4 and 5. Evaluation Weed percentage 0 0-9% 1 10-19% 2 20-29% 3 30-39% 4 40-49% 5 50-59% 6 60-69% 7 70-79% 8 80-89% 9 90 ~99% 10 100%

【table】

【table】

[Table] In the table, the calculated values indicate the expected values obtained from Colby's formula. As is clear from the table below, the composition of the present invention has greater synergistic herbicidal activity than the simple sum of the respective activities of the compound represented by the general formula () and the conventional herbicide. Furthermore, it is possible to selectively and completely control target weeds with a low dosage.

Claims (1)

[Claims] 1 General formula (): [In the formula, A represents lower alkyl. B represents a halogen atom or a lower alkoxy group. R represents a lower alkyl group. Z represents a nitrogen atom or a CH group. X and Y each independently represent a lower alkyl group or a lower alkoxy group. ] A pyrazolesulfonylurea derivative represented by A herbicide characterized by containing it as an active ingredient.