JPH0436127B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to general formula (I): [In the formula, A, B, and R represent lower alkyl groups. Z
represents a nitrogen atom or a CH group. X and Y each independently represent a lower alkyl group or a lower alkoxy group. ] The present invention relates to a herbicidal composition containing a pyrazolesulfonylurea derivative represented by the following and sodium chlorate (hereinafter referred to as sodium chlorate) as active ingredients. 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 herbicidal properties. The compound represented by the general formula (I) exhibits an excellent herbicidal effect at a very low dose compared to conventional herbicides. As a result of research aimed at increasing their effectiveness, we found that when the compound represented by the general formula is combined with the above-mentioned herbicides that are conventionally used, the herbicidal effects of each herbicide are not only additive but also synergistic. He discovered that the herbicidal effect appeared and completed the present invention. This synergistic effect is great, and the composition of the present invention can completely control both annual and perennial weeds with a low dose, making the present invention extremely useful. Moreover, the above-mentioned mixed application also makes it possible to reduce the amount of the conventionally used herbicide contained in the composition of the present invention, which is extremely useful. The herbicide composition of the present invention is effective even when treated before and after weed germination, and is highly effective when treated in soil or in foliage and soil treatment. It can also be applied to control various weeds in agricultural and horticultural fields such as fields and orchards, as well as non-agricultural lands such as playgrounds, vacant lots, forest areas, tank yards, and railway edges, and exhibits great economic effects in weed control. Depending on the relative activity of each component, the composition according to the present invention generally contains 0.0001 to 50 parts by weight, preferably 0.001 to 10 parts by weight of the compound represented by formula (I) per 1 part by weight of sodium chlorate. Contains. In many cases, the greatest advantage of the combined herbicide of the invention is when the proportion of the compound of formula (I) is relatively lower than that of sodium chlorate, e.g. The compound that
Obtained when the amount is 0.001 to 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 the compounds represented by the general formula (I) in the present invention. Although the following compounds are included in the compounds represented by general formula (I), the compounds represented by general formula (I) are not limited to these.

【table】

[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 explained in more detail with reference to Examples, but the compounds, dosage amounts, dosage forms, etc. in the present invention are not limited only to the Examples. In addition, all "parts" mean parts by weight. Formulation example 1 Wettable powder Compound No. 2...0.5 parts Hexazinone...85 parts Chlorate soda...10.5 parts (Kaolin clay: trade name of Zeeklite Industries Co., Ltd.) Solpol 5039...2 parts (Nonionic interface Mixture of activator and anionic surfactant: Toho Chemical Co., Ltd. trade name) Carplex (anti-caking agent)...2 parts (White carbon: Shionogi & Co., Ltd. trade name) Mix and grind the above uniformly and use it as a hydrating agent. Formulation example 2 Wettable powder Compound No. 3...0.1 part Chlorate soda...80 parts Sieglite A...15.9 parts (Kaolin clay: Sieglite Industries Co., Ltd. trade name) Solpol 5039...2 parts (Non-ionic clay)... 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) Mix and grind to make a wettable powder. Formulation example 3 Wettable powder Compound No. 7...1 part Chlorate soda...85 parts Sieglite A...10.5 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) Mix and grind to make a wettable powder. Formulation example 4 Wettable powder Compound No. 8...1 part Chlorate soda...80 parts Siegrite A...15 parts (Kaolin clay: brand name of Sieglite Industries Co., Ltd.) 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) Mix and grind to make a wettable powder. Test example: Weeding effect test using stem and leaf/soil treatment Sterilized diluvial soil was placed in a plastic box measuring 15 cm in length, 22 cm in width, and 6 cm in depth, and 5 pieces of underground rhizomes of Chigaya and Mugwort collected from the field cut into 10 cm pieces each were placed. Each tree was planted and covered with soil about 1.5 cm.
On the 30th day after planting, the active ingredients were uniformly sprayed on the foliage and soil surface in a predetermined ratio.
The chemical solution used for spraying was the hydrating agent of the formulation example described above diluted with water and sprayed using a small sprayer over the foliage of various weeds and the entire surface of the soil. Four weeks after spraying the chemical solution, the weight of the above-ground living weeds was weighed, and the ratio of the remaining weeds to the weight of living weeds in the untreated area was expressed as a percentage, and the killing effect was evaluated according to the following criteria. The results are shown in Tables 2 and 3. Weed killing rate = (1 - Above-ground grass weight in treated area / Above-ground grass weight in untreated area x 100 Score Weed killing rate 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] 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 activities of the compound represented by general formula (I) and the conventionally known herbicides. Furthermore, target weeds can be completely controlled with a low dose.

Claims (1)

[Claims] 1 General formula (I): [In the formula, A, B, and R represent lower alkyl groups. 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 herbicide composition comprising a pyrazolesulfonylurea derivative represented by the following and sodium chlorate as active ingredients.