JPS61191602A - Herbicide composition - Google Patents

Abstract

PURPOSE:To provide a herbicide composition capable of completely exterminat ing from cockspur-grass and annual weeds to perennial weeds with a low dose by the synergetic effect, without giving phytotoxicity to rice plant, by compounding a specific pyrazolesulfonylurea with another compound, and using the compounds as active components. CONSTITUTION:The objective composition contains the pyrazolesulfonylurea of formula and S-benzyl-N-ethyl-N-(1,2-dimethylpropyl)-thiolcarbamate (com pound A) or S-benzyl-N-di-n-propylthiolcarbamate (compound B) as active components. The amount of the compound of formula is 0.001-10pts.wt. per 1pt. of the compound A or the compound B. EFFECT:The synergetic herbicidal effect is especially high against Deccan grass. It is useful also for the treatment of the field of various crops as well as rice plant. Effective to the treatment before or after the sprouting of the weeds, and also exhibits high effect by soil treatment or foliar and soil treatment.

Description

Detailed Description of the Invention The present invention relates to a pyrazolesulfonylurea and S-benzyl-N-ethyl-N-(1,2-dimethylpropyl)-thiol carbamate (hereinafter referred to as compound A) represented by formula (I): or S
-benzyl-N-di-n-propylthiol carbamate (hereinafter referred to as compound B) 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 chemicals with better herbicidal properties, and in particular, as herbicides for agriculture and horticulture, they are needed to selectively target only target weeds at low doses without causing harm to cultivated crops. Although it is desirable to control the disease, existing agents do not necessarily meet this requirement.

The compound represented by formula (1) exhibits an excellent herbicidal effect at a lower dose than conventional pesticides, and is highly safe for rice. In addition, it is highly effective not only against -year-old grass weeds and -year-old broad-leaved weeds, but also against perennial weeds, making it highly useful.

On the other hand, Compound A and Compound B are used in higher dosages than the compound represented by the formula (R) against weeds and annual weeds, but as a result, the number of perennial weeds that are difficult to control with these agents increases, resulting in no improvement. is desired.

The present inventor conducted research to increase the herbicidal effect of the compound represented by formula (1), and found that when compound A or compound B is added to the compound represented by formula (1), the respective herbicidal effects are increased. The present invention has been completed by discovering that the herbicidal effect is not only additive but also synergistic. The usefulness of the present invention is very great because it can completely control wild grasses, annual weeds, and perennial weeds with a low dosage.In particular, the synergistic herbicidal effect on barnyard grasses is extremely useful.

Furthermore, the herbicidal composition of the present invention is effective even when treated before and after weed germination, and is highly effective when treated with soil or with both foliage and 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. applicable,
Shows great economic effect in weed control.

Depending on the relative activities of each component, compositions according to the invention generally contain the formula (
It contains 0.001 to 50 parts by weight, preferably 0.001 to 10 parts by weight of the compound represented by 1).

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 in general amounts from 0.001 to IKg/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.

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 sum of the respective activities of the two compounds ( When the 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.

(Colby S, Calculation of synergistic and antagonistic responses of R8 herbicide combinations rWeedJ vol. 15, pp. 20-22, 1
967) α: Inhibition rate when herbicide A is treated at a Kg/ha amount β: Suppression rate E when herbicide B is treated at an amount of bKg/ha = Herbicide A at a Kg/ha ,,bKg/h of herbicide B
If the expected inhibition rate, that is, the actual inhibition rate when treated with the amount of a, 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.
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.

YK Medical Engineering Granule Compound (1) ・-1111・-0,07 parts Compound A −・−−−−−−−7 parts Bentonite −・−・−50 parts Talc −
...−・−・−42.93 parts or more are uniformly mixed and pulverized, then a small amount of water is added, stirred and kneaded, granulated with an extrusion granulator, and dried to form granules. .

■Kou 1 Granule Compound (1) −・−1−−−−−・−0,0
5-part compound B ・----------------------・l
O part bentonite -・-・・-・-50 parts talc ・−・・−−−−−−・ 39.95
After uniformly mixing and pulverizing more than one part, a small amount of water is added, the mixture is stirred and kneaded, and the mixture is granulated using an extrusion granulator and dried to form granules.

Armpit group 1 Weeding effect test under flooded conditions 115000
After putting alluvial soil into Earl's Hugnerbot, water is added and mixed to create a freshwater condition with a water depth of 2 cm. Seeds of Japanese grasshopper, broad-leaved weeds (Japanese chinensis, azalea, and Kikashigusa) were mixedly sown in the above-mentioned pots, and tubers of Japanese cypress, Japanese cypress, and black bream were also placed in the beds. Furthermore, rice seedlings at the 2.5 leaf stage were transplanted. 25-3 pots
Plants were grown in a greenhouse at 0° C., and 10 days after sowing, at the 1.5-leaf stage, a diluted drug solution was dropped onto the water surface using a volumetric pipette at a predetermined dose.

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% l --- Weed killing rate 5-19% 0 --- Weed killing rate 5% or less (mostly effective (None) However, the above-mentioned weed killing rate was determined by the following formula by measuring the weight of above-ground fresh grass in the chemically treated area and the above-ground fresh grass weight in the non-treated area.

Table 3-! 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 predetermined drug formulated into granules was applied to the hot water soil during the two-leaf stage of barnyard millet. The pots are placed in a greenhouse at 25-30℃ for controlled cultivation, and after treatment
The above-ground fresh grass weight of the barnyard grass remaining in the daily harvest and the above-ground fresh grass weight of the untreated area were measured, and the weed killing rate was calculated and judged according to the following criteria. The results are shown in Tables 4 and 5.

Rating: Weed killing rate Below: Margin Table 5 In Table 5, the calculated values indicate the expected values determined from the Colby 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 (1) and the conventionally known herbicides. Furthermore, it is possible to selectively and completely control target weeds with a low dosage.

Claims (1)

[Claims] Formula (I): ▲Mathematical formulas, chemical formulas, tables, etc.▼Pyrazolesulfonylurea and S-benzyl-N-ethyl-N-(1,2-dimethylpropyl)- represented by (I) Thiol carbamate or S-benzyl-N-di-n-
A herbicide composition containing any one of propylthiol carbamates as an active ingredient.