JPH0363524B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention is based on the general formula (): [In the formula, A represents a lower alkyl group. B represents a hydrogen atom or a lower alkyl group. R represents a lower alkyl group. X and Y each independently represent a lower alkyl group or a lower alkoxy group. ] Pyrazolesulfonylurea derivative represented by and 2-benzothiazol-2-yloxy-N-
Methylacetanilide (hereinafter referred to as NTN801)
4-ethoxy-methoxy-benz-2',3'-dichloroanilide (hereinafter referred to as HW-52), N-butoxymethyl-2,6-diethyl-α-chloroacetanilide (hereinafter referred to as butachlor) or 2- The present invention relates to a herbicidal composition containing as an active ingredient one of cuchlor-2'6'-diethyl-N-(n-propoxyethyl)acetanilide (hereinafter referred to as pretilachlor). 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 the general formula () has an excellent herbicidal effect at a lower dose than conventional herbicides, and is highly safe for rice. In addition, it is highly effective not only against annual grass weeds and annual broad-leaved weeds, but also against perennial weeds, making it highly useful. Also, the conventionally known NTN801, HW-
52 has been used against wildflowers, and butachlor or pretilachlor has been used in higher doses than the compound represented by the general formula () against wildflowers, annual weeds, and firefly, but as a result, it has been difficult to control them with these drugs. 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 conventionally used herbicide is added to the compound represented by the general formula (), The present invention was completed by discovering that not only the respective herbicidal effects can be obtained additively, but also a synergistic herbicidal effect appears.
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. In addition, the synergistic effect of the herbicidal effect on barnyard grass is particularly remarkable, and by the above-mentioned mixed application, it is possible to reduce the amount of the conventionally used herbicides contained in the composition of the present invention, which is extremely useful. Highly sexual. 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 also be obtained by treating both the leaves and the soil. 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 present invention generally comprises 0.001 to 50 parts by weight of the compound represented by the general formula () per part by weight of NTN801, HW-52, butacuclor or pretilachlor, depending on the relative activity of each component;
It is preferably contained in an amount of 0.001 to 10 parts by weight. In many cases, the greatest advantage of the combined herbicides of the present invention is when the proportion of compounds of the formula () is relatively low compared to other herbicides, e.g. The compound represented by is 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 particular species of target plant 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. (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 β: Inhibition rate when treated with herbicide B at bKg/ha E: 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 further explained in 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. 2 ...0.1 part HW-52 ...7 parts bentonite ...50 parts talc ...42.9 parts After uniformly mixing and pulverizing the above, add a small amount of water and mix and knead. The product is granulated using an extrusion granulator and dried to form granules. Formulation example 2 Granule compound No. 5...0.05 parts NTN801...3 parts Bentonite...50 parts Talc...46.95 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 Granule compound No. 6 ...0.1 part butachlor ...3.5 parts bentonite ...25 parts talc ...71.4 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 4 Granule compound No. 8 ...0.05 parts pretilachlor ...1.5 parts bentonite ...2.5 parts talc ...73.45 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 5 Wettable powder compound No. 7...0.3 parts HW-52...40 Sieglite A...55.7 parts (Kaolin clay: Sieglite Industries Co., Ltd. trade name) Solpol 5039...2 parts (non-ionic Mixture of anionic surfactant and anionic surfactant: Toho Chemical Co., Ltd. (trade name) Carplex (anti-caking agent)... 2 parts White carbon: Shionogi & Co., Ltd. (trade name) The above are mixed uniformly. Grind and use as a hydrating agent. Test Example 1 Weeding effect test under flooded conditions After putting alluvial soil in a 1/5000 are Wagner pot, add water and mix to create freshwater conditions 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℃
Plants were grown in a greenhouse, and 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 was determined by the following formula by measuring the weight of above-ground plants in the chemically treated area and the weight of above-ground plants in the non-treated area. Weed killing rate = (1 - above-ground grass weight in treated area / above-ground grass weight in non-treated area) x 100

【table】

[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, Japanese millet was grown in the paddy field, and each prescribed drug formulated into granules was flooded at the third leaf stage of barnyard millet. Soil treated. The pots were placed in a greenhouse at 25 to 30℃ and grown under control. 30 days after treatment, the weight of the remaining above-ground grass of barnyard grass and the weight of the 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. Score Weed killing rate 0 1-9% 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] In the table, the calculated values indicate the expected values obtained from Colby's formula. As is clear from the above table, 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 conventionally known 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 a lower alkyl group. B represents a hydrogen atom or a lower alkyl group. R represents a lower alkyl group. X and Y each independently represent a lower alkyl group or a lower alkoxy group. ] Pyrazolesulfonylurea derivative represented by 2-benzothiazol-2-yloxy-N-methylacetanilide, 4-ethoxy-methoxy-
Benz-2,3'-dichloroanilide, N-butoxymethyl-2,6-diethyl-α-chloroacetanilide or 2-chloro-2'6'-diethyl-N
-(n-propoxyethyl)acetanilide as an active ingredient.