JPH02152908A - Herbicide for field crop cultivation - Google Patents

Abstract

PURPOSE:To obtain a herbicide for field crop cultivation having enhanced weeding effect and reducing administrating dose to reduce phytotoxicity to field crop by jointly using specific herbicide exhibiting excellent weeding effect to Gramineous weed and specific herbicide exhibiting excellent weeding effect to broad leaf weed. CONSTITUTION:(A) 1 pt. 2-{2-[4-(3,5-dichlorpyridine-2-yloxy)phenoxy] propionyl} isooxazolidine expressed by formula I is mixed with (B) 1.10 pts. 1-phenyl-4- amino-5-chlorpyridazone-6 and said mixture of two components is mixed into the aimed herbicide as active ingredients to afford a herbicide exhibiting excellent weeding effect which cannot be expected from individual single active ingredient preparation against annual-perennial weeds in culturing field of field crop with low administration dose and thus without fear of giving any phytotoxicity to field crop, and usable for broad treating season from before generation of weeds to growing season.

Description

[Detailed description of the invention] Rie erect father-in-law Yuji! The present invention relates to a herbicide for field use.

As a field herbicide, Aisuemu has a wide herbicidal spectrum and residual effect that can kill weeds ranging from annual weeds to perennial weeds with the use of a small amount, and it also has a residual effect that kills weeds even before they emerge. It is desirable that it can be used at a wide range of processing times up to the end of the season, and that it has low toxicity to humans and animals and does not cause chemical damage to crops. However, in reality, there are very few herbicides that meet these demands, especially those that are highly effective against perennial weeds and can be used over a wide range of treatment periods.

On the other hand, one active ingredient of the present invention is 2-(2-(4-(3,
5-dichloropyridin-2-yloxy)phenoxy)
propionyl) isoxazolidine (this compound contains 4
Compound A (hereinafter collectively referred to as "Compound A", which exists in either Compound A or Racemic Compound unless otherwise specified) is known as a herbicide in Japanese Patent Publication No. 16389/1989. This compound A can be applied to crabgrass, foxtail grass, and other plants by either soil treatment or foliage treatment.
It exhibits an excellent herbicidal effect against grass weeds such as grass weeds and grasshopper, and does not cause damage to broad-leaved crops such as sugar beet, soybean, and radish. However, it has the disadvantage that the herbicidal effect is extremely low against perennial weeds, such as sagebrush and horsetail, even if it is treated during the germination or growth period.

In addition, the other active ingredient 1-phenyl-4-amino-
5-Chlorpyridazone-6 (hereinafter referred to as "Compound B")
"Pesticide Handbook 1985 Edition" (Incorporated Association
Japanese Plant Protection Association (Published January 30, 1986) No. 3
Page 79, “Short Review Saibu 8-Beside 1
It is a well-known herbicide, as described on page 164 of ``986 Edition'' (National Rural Education Association, November 1985). Compound B does not cause any phytotoxicity to sugar beet when treated with soil and leaves, and it is effective in
Compound B has a high herbicidal effect on broad-leaved weeds such as whiteweed, grasshopper, cornucopia, shepherd's purse, and mustard.
is less effective against grass weeds, and causes damage to broad-leaved crops other than sugar beet, such as soybeans, adzuki beans, and spinach. In addition, ethyl 2-(4-(6-chloro-
The use of a mixture of 2-quinoxanyloxy)phenoxy]propionate and the compound ThB as a herbicide is known from JP-A-57-131703. but,
This mixture cannot be said to be preferable due to the relationship between herbicidal effect and phytotoxicity to crops.

Problems to be Solved by the Invention Therefore, the present invention is highly effective against annual weeds and perennial weeds in fields where field crops such as sugar beets, soybeans, adzuki beans, and spinach are cultivated. The objective is to provide a new herbicide that can be used during the treatment period.

The inventors of the present invention have conducted extensive studies to solve the above-mentioned problems. As a result, we found that the combination of compound A and compound B shown below produces excellent properties that cannot be expected from the single use of these compounds.
The invention has been completed.

Chemical name: 2-(2-(4-(3,5-dichloropyridin-2-yloxy)phenoxy]propionyl)isoxazolidine Chemical name: l-phenyl-4-amino-5-chlorpyridazone-6 1" Present invention Compound A and compound %lB used in Table 1 act as active ingredients of the field herbicide of the present invention.

- (Method of) The wheat-acting herbicide of the present invention can be made into a wettable powder, a flowable (sol), etc. by a conventional method together with two types of active ingredients consisting of Compound A and Compound B, a carrier, and various auxiliaries. It can be formulated and used. The carriers used include solid carriers such as clay, talc, bentonite, kaolin, diatom, silica, and sucrose, or water, alcohols (methanol, ethanol, isopropanol, etc.), glycols (ethylene glycol, Liquid carriers such as propylene glycol and the like are used. These can be formulated with appropriate amounts of surfactants and other auxiliary agents, such as stabilizers and spreading agents, for use.

The appropriate blending ratio of the active ingredients in the present invention is 1 part of Compound A to 1 to 10 parts of Compound B by weight. However, the blending ratio can be changed as appropriate depending on the conditions at the time of application. Further, other herbicides, fungicides, insecticides, plant 51m agents, etc. can also be mixed and used.

Further, Compound A (d-form, !L-form, racemic form: d-like i) can be produced by the method described in Tokukan Sho 63-16389. And the compound ThAtt
It can be effectively used in any form of d-form, steric form, or racemic form.

Next, examples of formulation of field herbicides of the present invention will be shown. However, in the examples, all parts are parts by weight.

Example 1 (Wettable powder) 30 parts of compound A (racemic form), 50 parts of compound ￥lllB, 5 parts of polyoxyethylene alkylaryl ether, calci lignin sulfonate, 3 parts of rum, and 32 parts of clay were mixed and thoroughly ground. death.

Obtain a hydrating powder.

Application 2 (hydrating agent) Compound A (d form) 20 parts, Compound 8 40 parts.

5 parts of polyoxyethylene alkylaryl ether, 3 parts of calcium lignin sulfonate, and 32 parts of clay
Mix the parts and thoroughly grind to obtain a wettable powder.

Example 3 (70) 25 parts of compound A (racemic form), 25 parts of compound B, 1 part of sodium alkylnaphthalene sulfonate, 3 parts of sodium lignin sulfonate, 0.3 parts of xanthan gum, and 45.7 parts of water were uniformly mixed. and get a flowable.

-4 (Flowable) Compound A (d form) 20 parts, Compound 8 40 parts.

1 part of sodium alkylnaphthalene sulfonate, 3 parts of sodium lignin sulfonate, 0.
3 parts and 35.7 parts of water are uniformly mixed to obtain a flowable.

The hydrating agents and flowables of Examples 1 to 4 above are diluted with water and adjusted to 21!1 so that the active ingredient is 10 to 100 g per 10 are, and processed with a chemical solution of 5 to 1501 per 10 are. , a high weeding effect can be obtained.

Appearance ΩA1 When the field herbicide of the present invention is used as a mixture of Compound A and Compound B in cultivation areas for field crops, it exhibits a superior herbicidal effect compared to when each of them is used mutatis mutandis.

That is, first of all, weeds of the grass family that have grown from pre-emergence to around the four-leaf stage (such as sycamore, sycamore, hackberry, and sycamore) and broad-leaved weeds (such as chickweed, japonica, japonica, staghorn, japonica, shepherd's purse, etc.) It exhibits an excellent weeding effect on difficult-to-weed commonweeds, as well as the perennial weeds such as Japanese horsetail, horsetail, grasshopper, chinese grass, and johnson grass, causing them to wither.

Secondly, the method of use shows high herbicidal effects in both soil treatment and foliage treatment, and is sustainable, so that the reproduction of many of the above-mentioned weeds can be continuously inhibited.

Thirdly, it does not cause phytotoxicity to field crops such as sugar beets, soybeans, adzuki beans, spinach, etc., either transplanted or directly sown, or to many varieties of crops.

Fourthly, the field herbicide of the present invention contains compound A and compound B.
The two will strengthen each other and exhibit high weeding effects without compromising the strengths of each. Moreover, the effect is
It becomes more pronounced when small doses are used. Therefore, in the present invention, it is possible to exhibit high selectivity without worrying about chemical damage to field crops by using a small amount of chemical, and to exhibit high herbicidal effects against various grass weeds and broad-leaved weeds, leading to their death. be able to.

However, the combined use of Compound A and Compound B in the present invention is useful as a field herbicide.

Next, the usefulness of the field herbicide of the present invention will be explained using test examples.

Grass test using soil (pot test) Fill a plastic pot with a size of 172,000 ares with field soil (alluvial loam), and add weeds such as crabgrass, hackberry, sycamore, chickweed, pigweed, and shepherd's purse on top of this. 30 seeds of each were sown, these seeds were uniformly mixed with the soil in the surface layer of 1 cm, and the surface layer was lightly pressed. In addition, 10 seeds each of sugar beet, soybean, adzuki bean, and spinach were sown in M pots, and 2 seeds of sugar beet were sown at the same time.
Seedlings at ~3 leaf stage were transplanted into separate pots. Then, on the day after sowing, ai*t was prepared according to Example 2, and the hydrating agent was diluted with water to adjust the amount of active ingredient used per 10 are as shown in Table 1. 20 per 10 ares of solution
The soil surface of each pot was sprayed at a rate of 41%.

This test was conducted using a system of 3 bottles per drug-treated area. Then, after 30 days of chemical treatment, the above-ground parts of the weeds that survived were cut off, their hay type i (g) was measured, and the average weeding rate (%°) for the three plots was determined using a linear equation.

In addition, the above-ground parts of sugar beets, soybeans, adzuki beans, and spinach were also cut off, their dry weights (g) were measured, and the degree of chemical damage to each crop (inhibition rate (2)) was determined according to the method used to calculate herbicidal rates. The degree of drug damage was indicated according to the criteria shown below.

Chemical damage level 5: Suppression rate of 90% or more 4: Suppression rate of 70 to less than 90% 3:
Push-open rate 40-less than 70% 2...Suppression rate 20-4
Less than 0% l... Suppression rate S - less than 20% O...
...Suppression rate less than 5% The results are shown in Table 1.

Enter! ■l Weeding effect by stem and leaf path (Pot 172
Field soil (alluvial loam) was filled in a plastic pot with a size of 1,000 ares, and 20 seeds each of each of the following weeds were sown on top of the pot: grasshopper, hackberry, sycamore, stagweed, chickweed, ragweed, and shepherd's purse. Then, 1 cm of surface layer of soil and these seeds were uniformly mixed and one surface layer was lightly pressed. Also, sugar beets, soybeans,
Sow 10 seeds of red beans and spinach.

At the same time, three sugar beet seedlings ranging from 2 to 31J were transplanted to different pots. And each weed is in the 2nd to 411th stage, direct sown sugar beet is in the 3rd leaf stage, transplanted sugar beet is in the 5th to 6th leaf stage, soybeans and adzuki beans are in the first compound leaf stage, and spinach is in the 2nd to 3rd leaf stage! In period #, the wettable powder prepared according to Example 1 was diluted with water to adjust the amount of active ingredient used per 10 are as shown in Table 2, and this drug solution was added to 10 are. The 0-bottle test, in which weeds and the foliage of crops were sprayed at a rate of 201 per drug, was conducted using a system of 3 bottles per chemical solution concentration group. Then, 30 days after the chemical treatment, the surviving weeds and above-ground parts of the crops were extracted, their dry weight (g) was measured, and the weeding rate (%) was measured in the same manner as in Test Example 1.
) and the degree of chemical damage to crops.

The results are shown in Table 2.

Test Example 3 As a test method for herbicidal effect and chemical damage in the field, a test plot with an area of 1 orn' was created,
For each plot, grasshopper (5g), staghorn grass (4g), Ezonogishigishi (5g), and Butafusa (6g) were sown. Also sugar beet seeds, soybean seeds, red bean seeds, spinach seeds and sugar beet +'+
'r (three-leaf stage) was sown or transplanted at the same time. The day after sowing, dilute the wettable powder prepared according to Example 1 with water,
The amount of active ingredient used per 10 are was adjusted to be the amount shown in Table 3, and this chemical solution was uniformly sprayed at a rate of 20 times per 10 are.

This test was conducted in three consecutive sessions in each section. And after 30 days of chemical treatment, there were survivors from 3 locations in the test area (equivalent to 3 faces)! y and the above-ground part of the crop were cut off and their dry weight (g) was determined, and in the same manner as Test Example 1, the herbicidal rate (%) and the degree of chemical damage to the crop (suppression rate (%)) were determined.

The results are shown in Table 3.

As a test method for grass and drug damage in a field, test plots with an area of 1 plot or iogo were created, and each plot contained 5 g of grass, 4 g of blackberry, and 4 g of grass 5g) and pigweed (6g) were sown.

In addition, sugar beet seeds, soybean seeds, adzuki bean seeds, spinach seeds, and sugar beet seedlings (three-leaf stage) were sown or transplanted at the same time.

Weeds or 2-3! Example 2 at # stage, when directly sown sugar beets reached the 3-leaf stage, transplanted sugar beets at the 5-6 leaf stage, soybeans and adzuki beans at the first compound leaf stage, and spinach at the 2-3 leaf stage.
The weeding rate (%) and the degree of chemical damage to crops (inhibition rate (%)) were determined using a hydrating powder prepared according to the method described above.

The results are shown in Table 4.

The amount of active ingredient used per 10 are was adjusted to W7 as shown in the Type 4 Table, and the solution was sprayed on the foliage of weeds and crops at a rate of 20 per 10 are.

Claims (1)

[Claims] A mixture of two types of 2-{2-(4-(3,5-dichloropyridin-2-yloxy)phenoxy)propionyl}isoxazolidine and 1-phenyl-4-amino-5-chlorpyridazone-6 as the active ingredient. A field herbicide characterized by containing: