JPS5995207A - Herbicidal composition - Google Patents

Abstract

PURPOSE:To provide a herbicidal composition containing an N-phenyltetra- hydrophthalimide derivative and 3-isopropyl-1H-2,1,3-benzothiadiazin-4(3H)-one 2,2-dioxides, and effective especially in soybean field. CONSTITUTION:The objective herbicidal composition contains (A) the compound of formula [R is lower alkyl, cycloalkyl or halo(lower alkyl)] and (B) 3-isopropyl-1H-2,1,3-benzothiadiazin-4(3H)-one 2,2-dioxide or its salt at a weight ratio of 1:1-20. The composition has selective herbicidal activity to wide variety of weeds (e.g. common morning-glory, sensitive-joint-vetch, etc.) especially in soybean field, and is effective at a low rate of application since the herbicidal effect is synergistically increased compared with the separate use of each component.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is based on the general formula [wherein R represents a lower alkyl group, a cycloalkyl group, or a halo-lower alkyl group]. ] (hereinafter referred to as compound (1)
]. ) and 3-itubropyruIH-2,1,3-
A herbicidal composition containing benzthiadiazin-4(3H)-one 2,2-dioxide (hereinafter referred to as hentazone) or a salt thereof as an active ingredient (
Hereinafter, it will be referred to as the composition of the present invention. ) (This is related to this.)

Currently, a large number of herbicides are used as herbicides for upland fields, but because there are many types of weeds to control and their emergence takes a long time, the herbicidal effect is less than 1%, and the herbicidal spectrum is wide. There is a need for herbicides that are both safe for crops and have the same properties.

As a result of various studies to develop a herbicide that meets these objectives, the present inventors have found that the composition of the present invention containing compound (I) and pentacine or its salt as active ingredients is effective against various weeds, In particular, it has been found that a wide range of weeds in Thai rice fields can be selectively weeded, and that the herbicidal effect is synergistically increased compared to when they are used alone, and that they can be applied at low dosages, and have developed the present invention. completed.

The weeds targeted by the composition of the present invention include morning snails such as whiteweed, blueberry, vertical chickweed, chickweed, purslane, Japanese snail, Japanese morning glory, Japanese thornweed, commonweed, and other morning glories;
There are dicotyledonous plants such as Physalis and wild sunflower, and monocotyledonous plants such as foxtail grass, black-and-white grass, black-and-white grass, blackberry, and Seiban sorghum. , and American oxaneum can be weeded at the same time.

Compound [Technical] (Patent Application No. 1987-212896, long-awaited application 1)
S57-13845, Japanese Patent Application No. 57-17858) has a herbicidal effect and also contains pentacine or its salt [He
rbicide 1(andbook of the
WeedScience 5ociety of Am
Erica, 4th edition, p. 49 (1979)] is
It is known as a weed killer for rice.

The mixing ratio of compound [11] and pentacine (or its salt), which are the active ingredients of the composition of the present invention, can be varied within a relatively wide range, but it is usually per 111 parts by weight of compound [11] and pentacine (or its salt). or its salt) 0.5-10
0 parts by weight, preferably 1 to 20 parts by weight. Table 1 shows some compounds tI which are active ingredients of the composition of the present invention.

Table 1 When the composition of the present invention is used as a herbicide, it is usually formulated into an emulsion, wettable powder, suspension, etc. using a solid carrier, a liquid carrier, a surfactant, and other formulation auxiliaries.

These preparations contain active ingredients in a weight ratio of 05 to 90%, preferably 2 to 80%.

Solid carriers include fine powders or granules such as kaolin clay, acpulgite clay, bentonite, acid clay, pyrophyllite, talc, diatomaceous earth, calcite, walnut powder, urea, ammonium sulfate, and synthetic hydrous silicon oxide; Supports include aromatic hydrocarbons such as xylene and methylnaphthalene, alcohols such as isopropanol, ethylene glycol, and cellosolve, ketones such as acetone, cyclohexanone, and isophorone, vegetable oils such as soybean oil and cottonseed oil, dimethyl sulfoxide, Examples include acetonitrile and water.

Surfactants used for emulsification, dispersion, wetting, etc. include negative salts such as alkyl sulfate salts, alkyl (aryl) sulfonate salts, dialkyl sulfosuccinate salts, and polyoxyethylene alkylaryl ether phosphate salts. ionic surfactant, polyoxyethylene alkyl ether, polyoxyethylene alkylaryl ether,
Examples include nonionic surfactants such as polyoxyethylene phosphoryoxypropylene block copolymers, sorbitan fatty acid esters, and polyoxyethylene sorbitan fatty acid esters. Formulation adjuvants include lignin sulfonate, alginate, folivinyl alcohol, gum arahia, C.
Examples include MC (carboxymethyl cellulose) and PAP (isopropyl acid phosphate).

Examples of formulations are shown below. In addition, the active ingredient is a chemical compound [1]
is indicated by the compound number in Table 1, and parts are indicated by weight - Formulation Example 1 10 parts of compound (1) or (3), 10 parts of pentacine (sodium salt), 10 parts of synthetic hydrous silicon oxide, 3 parts of alkyl sulfate 1 part, 2 parts of calcium ligninsulfonate, and 65 parts of diatomaceous earth are thoroughly ground and mixed to obtain a wettable powder.

Formulation Example 2 4 parts of compound (2), 2 parts of pentacine, 14 parts of polyoxyethylene styrylphenyl ether, 6 parts of calcium dotesylbenzenesulfonate, 34 parts of xylene and 40 parts of cyclohexanone are thoroughly mixed to obtain an emulsion.

Formulation Example 8 5 parts of compound (2) or (4), 3 parts of polyoxyethylene solhicum monooleate, 3 parts of 0MO, and 69 parts of water were mixed and wet-pulverized until the particle size of the active ingredient became 5 microns or less. , 20 parts of pentacine (sodium salt) are dissolved to obtain a suspension.

These preparations are diluted with water and sprayed on foliage.

By mixing it with other herbicides, it is expected that the herbicidal efficacy will be enhanced. It can also be used in combination with insecticides, acaricides, nematicides, fungicides, plant growth regulators, fertilizers, soil conditioners, and the like. The composition of the present invention and the application amount are based on weather conditions, soil conditions, the formulation form of the composition, and the mixing ratio of active ingredients from 1.5 to 202. Emulsions, wettable powders, suspension agents, etc. have a concentration of 1 to 10 liters per are (
If necessary, apply diluted with water (added with spreading aids such as spreading agents).

Spreading agents include, in addition to the above-mentioned surfactants, polyoxyethylene resin acids (esters), lignin sulfonates, ahietates, dinaphthylmethane disulfonates, paraffins, and the like.

Next, test examples will be given to illustrate specific examples of the herbicidal effect of the composition of the present invention.

The herbicidal efficacy was determined by measuring the fresh weight of the above-ground parts of the test plants that remained withered at the time of the survey, and calculated the dead head suppression rate tl using the following formula.
'6+ indicates.

Test Example 1 A cylindrical plastic box with a diameter of 1 oc 11 1 and a depth of 1 oc 11 was filled with field soil, and seeds of Malva saccao or American americanus were sown, and the seeds were grown outdoors for 20 days after being poured into the soil. A predetermined amount of the composition of the present invention made into a wettable powder according to Formulation Example 1 was diluted with water containing a spreading agent, and 5
The foliage was sprayed using a small sprayer from above the plastic pot at the rate of a little powder. At the time of spraying, the morning glory was in the two-leaf stage, and the A. americanae was in the two-leaf compound stage. After spraying, the plants were grown outdoors for 20 days and their herbicidal efficacy was investigated.

The results are shown in Tables 2 and 3.

Table 2 Herbicidal efficacy against morning glory Table 3
Herbicidal efficacy test example 2 against American hornwort. Field soil treatment test ■ Paddle 33 x 23 cm', depth 11. Fill a vat with upland soil, dilute the specified amount of morning glory, Japanese fir tree, whiteberry, american oxaneum, blueberry, and ax with water containing a spreading agent, and spray the plants at a rate of 5 liters per area. Sprayed evenly over the entire stem and leaves using a small sprayer from above.

At this time, the growth of each plant varies depending on the grass species, but it is in the 1-4 leaf stage and the plant height is 3-15 cm. Met. Twenty days after spraying, the herbicidal efficacy was measured. The results are shown in Table 4. Note that this test was conducted outdoors throughout the entire period.

Table 4: Various weeds (effects against them) -37!

Claims (1)

[Scope of Claims] General formula [wherein R represents a lower alkyl group, a cycloalkyl group, or a halo-lower alkyl group]. ] and 3-isopropyl-II4-2.1゜3-benzothiadiazine-4 (8H
)-one 2,2-dioxide or a salt thereof as an active ingredient.