JP3108890B2 - Paddy field herbicide composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel paddy field herbicide composition.

[0002]

2. Description of the Related Art Although many types of herbicides for rice action have been put on the market and used, there is still a strong demand in the market for improving their performance, safety and reducing phytotoxicity. In addition, many of the paddy field weeds occur for a long period of time without coincidence, and the weeds grow at various stages of growth, from those before germination to those that have grown to some extent when sprayed with herbicides. They are always mixed. For this reason, it is not possible to obtain a satisfactory herbicidal effect by a single application of the herbicide, and the herbicide must be applied several times.

[0003]

DISCLOSURE OF THE INVENTION The present inventors have sought to find a herbicide that can completely control various kinds of paddy field weeds in a single application, maintain its effect for a long period of time, and has extremely small phytotoxicity. As a result of the continuation, 3N- (2-fluoro-4-chloro-
5-cyclopentyloxyphenyl) -5-isopropylidene-1,3-oxazolidine-2,4-dione (hereinafter referred to as compound [A]) and 1- (2-chlorobenzyl) -3- (α, α -Dimethylbenzyl) urea (hereinafter, referred to as compound [B]) in an appropriate ratio was applied to obtain an extremely remarkable synergistic effect, which is much higher than expected, and the present invention was completed.

[0004]

The herbicidal composition for paddy fields of the present invention is characterized by containing the compound [A] and the compound [B] as active ingredients. In addition, the herbicidal effect is excellent and the safety to rice is high, and each active ingredient has an excellent synergistic effect which cannot be expected from the herbicidal effect exhibited alone. That is, the present invention provides 3N- (2
-Fluoro-4-chloro-5-cyclopentyloxyphenyl) -5-isopropylidene-1,3-oxazolidine-2,4-dione and 1- (2-chlorobenzyl) -3- (α, α-dimethylbenzyl) An object of the present invention is to provide a herbicide composition for a paddy field, comprising urea as an active ingredient.

[0005]

When the compound [A] is used alone as a herbicide for paddy fields, it has a broad spectrum from annual weeds, such as red snapper, tamayatsuri, and konagi, to perennial weeds, such as fireflies, pine trees, shrews, and black gross. It shows strong herbicidal activity and long-term residual effect on annual weeds before germination. However, when the growth of weeds progresses to a certain extent, the herbicidal effect is weakened, and the effect is particularly insufficient on perennial weeds such as fireflies, pine stalks, shrews and croakers. In addition, when the compound (B) is used alone as a paddy herbicide, especially for cyperaceae weeds such as stag beetle, pine stalk, firefly, scorpion grass, and black clover, a wide range from those before germination to those that have grown to some extent. Shows effect over time. In addition, it is highly safe for paddy rice and has great efficacy as a paddy herbicide. However, with respect to weeds other than Cyperaceae, the weeding effect is weakened when the growth of the weed progresses to a certain extent, and the effect is particularly insufficient against broadleaf weeds and grass weeds such as growing rice flour.

[0006] The present inventors not only compensate for the disadvantages of each drug, but also by extremely mixing and using the compound [A] and the compound [B] each having the above-mentioned characteristics at an appropriate ratio. We have found the fact that it shows a remarkable synergistic effect.

The proportion of each active ingredient in the herbicidal composition for paddy fields of the present invention is not particularly limited, and an excellent synergistic effect can be obtained in a wide blending ratio. The compound [B] is suitably about 0.5 to 20 parts by weight.

When the herbicidal composition for a paddy field of the present invention is used, an appropriate amount of each active ingredient is mixed with an inert carrier, and granules, fine granules, and wettable powders which are used in a general agricultural chemical form are prepared. , Emulsions, powders, flowables and the like.

[0009] Solid carriers include calcium carbonate, apatite, gypsum, silica gel, vermiculite, mica,
Ore powders such as diatomaceous earth, talc, pyroferrite, acid clay, clay, kaolinite, montmorillonite, bentonite, white carbon, pumice powder, etc., crystalline cellulose, starch and other vegetable powders, polyvinyl chloride, petroleum resin etc. And molecular compounds.

Examples of the liquid carrier include alcohols such as methanol, ethanol, cyclohexanol, amyl alcohol, and ethylene glycol; aromatic hydrocarbons such as benzene, toluene, xylene and methylnaphthalene; and halogenated hydrocarbons such as chlorobenzene and trichloroethylene. And ethers such as ethyl cellosolve, butyl cellosolve, and dioxane, esters such as isopropyl acetate and benzyl acetate, polar solvents such as dimethyl sulfoxide, kerosene, mineral oil, and water.

[0011] Further, if necessary in the formulation, adjuvants used in agricultural chemicals such as surfactants, spreading agents, binders, etc. or stabilizers may be mixed to increase the certainty of the herbicidal effect. it can.

The herbicidal composition for paddy fields of the present invention may contain an insecticide, a fungicide, a plant growth regulator, a fertilizer, or other herbicides, if necessary. They can be used together.

The amount of each active ingredient used in preparing the paddy field herbicidal composition of the present invention varies depending on the application scene, application timing, application method, target weeds, and the like. [A] is generally 5 to 500 g,
The suitable amount is preferably 10 to 250 g, and the compound [B] is generally in the range of 10 to 1,000 g, preferably 20 to 500 g.

The content of the total active ingredient in these preparations is generally 1 to 90% by weight, preferably 3 to 80%.
A range of% is appropriate.

[0015]

EXAMPLES Next, formulation examples of the paddy field herbicide composition of the present invention will be described, but the present invention is not limited thereto. In the preparation examples, "parts" indicates parts by weight.

Formulation Example 1 (Wettable powder) 4.5 parts of compound [A], 15 parts of compound [B], talc 7
5.5 parts, alkylaryl sulfonate 2 parts and surfactant Solpol 800A (trade name: manufactured by Toho Chemical) 3
The resulting mixture was mixed and pulverized together with the resulting mixture to obtain a wettable powder.

Formulation Example 2 (granules) 1.5 parts of compound [A], 5 parts of compound [B], talc 60
Part, 30.5 parts of bentonite and 3 parts of ligninsulfonic acid were sufficiently pulverized and mixed, water was added, and the mixture was kneaded well. The mixture was granulated by an extrusion granulator and dried to obtain a granule.

Formulation Example 3 (Floable agent) 4.5 parts of compound [A], 15 parts of compound [B], 4 parts of ethylene glycol, 0.5 part of xanthan gum, 5 parts of solpol 3940 (trade name: manufactured by Toho Chemical), Lunox 10
1 part of 00C (trade name: manufactured by Toho Chemical Co., Ltd.) and 70 parts of water are mixed well, and wet granulated until the particle size becomes 5 microns or less.
A flowable was obtained. Next, the excellent herbicidal effect of the herbicidal composition for a paddy field of the present invention will be described with reference to test examples.

Test Example 1 (Greenhouse Pot Test) Paddy soil was packed in a plastic pot having a diameter of 16 cm.
An appropriate amount of water was added to the plant to remove the seeds, various types of weed seeds were sown on the surface of the soil, and tubers of Mizukaya were transplanted. On the next day, two 2.5-leaf rice plants (variety: Koshihikari) were planted at a depth of 1 cm. Thereafter, the cells were immersed in 3 cm of water and allowed to stand still at room temperature. Immediately after rice transplantation (before the emergence of rice millet) and 5 days after rice transplantation (the first leaf stage of rice millet)
Then, a predetermined amount of the granules prepared by the method described in Formulation Example 2 was sprayed. After that, it was left still in a greenhouse and sprinkled as needed. Forty days after the treatment with the chemical, the herbicidal effect and the phytotoxicity of rice were examined. Table 1 shows the results of the treatment immediately after rice transplantation.
Table 2 shows the results of the treatment 5 days after rice transplantation. In addition, the evaluation of the herbicidal effect and the phytotoxicity in the table was determined according to the following criteria.

Criterion for judging herbicidal effect Criterion for judging chemical damage 10: 100% control-: No harm 9: 90% control ±: Micro-harm 8: 80% control +: Small harm 7: 70% control 2+: Medium harm 6: 60% control 3+: Major harm 5: 50% control ×: Withering 4: 40% control 3: 30% control 2: 20% control 1: 10% control 0: 0% control

[0021]

[Table 1] a: Snapper b: Tamazuri c: Konagi d: Annual broadleaf (Azena, Kikasigusa) e: Firefly f: Matsubai g: Mizuyayatsuri

[0022]

[Table 2] a: Snapper b: Tamazuri c: Konagi d: Annual broadleaf (Azena, Kikasigusa) e: Firefly f: Matsubai g: Mizuyayatsuri

Test Example 2 (Field test) After cultivating, irrigating, shaving and leveling a general paddy field by a usual method, 0.8 m ² (0.8 mx 1
m), seeds of various paddy field weeds were sown, and tubers of Spodoptera litura were transplanted. Thereafter, a predetermined amount of the flowable prepared according to the method described in Preparation Example 3 was sprayed while maintaining the depth of flooding at 3 to 5 cm. Four days after the chemical treatment, two rice seedlings (variety: Koshihikari) at 2.2 to 2.5 leaf stage were planted and transplanted into two strains, and 15 rice plants were set in one section (4 days before transplantation, before weed emergence). ). The herbicidal effect and the phytotoxicity of rice were investigated 40 days after the chemical treatment, and the results are shown in Table 3. The evaluation of the herbicidal effect and the phytotoxicity was made according to the criteria shown in Test Example 1.

[0024]

[Table 3] Commercial agent C: 5-tert-butyl-3- (2,4-dichloro-5-isopropoxyphenyl) -1,3,4-oxadiazol-2 (3H) -one 8% 2-chloro-
2 ', 6'-diethyl-N- (butoxymethyl) acetanilide 12% a: foxtail b: tamayatsuri c: konagi d: annual broadleaf (Azena, Kikasigusa) e: firefly f: matsubai g:

Test Example 3 (Field Test) A common paddy field was plowed, filled with water, shaved, and leveled in a usual manner, and then divided into 1 m ² (1 m × 1 m) sections by a partition plate. 1cm from the ground surface, 3c
m, 5 cm and 5 cm were implanted at a depth of 5 and a total of 20 were implanted. Thereafter, while maintaining the flooding depth at 3 to 5 cm, a predetermined amount of the flowable agent prepared by the method shown in Formulation Example 3 was applied 3 days after transplantation of the Krogwi tuber (prior to the occurrence of the Krogwai tuber) and 15 days after the transplantation of the Krogwi tuber (the occurrence of the Krogwai tuber) First). The herbicidal effect on Kurogwai was examined over time (20 days and 80 days after the chemical treatment), and the results are shown in Tables 4 and 5. The evaluation of the herbicidal effect was made according to the criteria shown in Test Example 1.

[0026]

[Table 4]

[0027]

[Table 5]

[0028]

As is clear from Table 1, Table 2, Table 3, Table 4 and Table 5, the herbicidal composition for paddy fields of the present invention has higher herbicidal activity as compared with the case where each active ingredient is applied alone. Is significantly enhanced. This is due to synergy between the active ingredients, and it is recognized that there is significant synergy. That is, the most significant feature of the herbicidal composition for paddy fields of the present invention is that a high herbicidal effect on many weeds is obtained by a combination of low doses which could not be expected from the herbicidal effect of each active ingredient alone. There are points that can be done.

Further, the herbicidal composition for paddy fields of the present invention exhibits remarkable herbicidal activity not only on weeds at an early stage of growth but also on weeds at a stage where growth has progressed to a certain extent, and furthermore, the safety against paddy rice is improved. Since it is very high and does not cause phytotoxicity, the herbicidal composition for a paddy field of the present invention can be sprayed from immediately after rice transplanting to during the growing season of weeds from the time of shaving before rice transplanting. In addition, there are many types of weeds that can be controlled, including annual weeds such as nobies, tamayatsuri and konagi,
Significant effects are also observed on perennial weeds such as pine byes, fireflies, sedges and black clover. Moreover,
Since each active ingredient has a long residual effect, it exhibits a high herbicidal activity over a long period of time and can control many weeds, so that it greatly contributes to a reduction in spraying labor, that is, a labor saving in agricultural work.

As described above, the herbicidal composition for paddy fields of the present invention has many excellent features and is highly practical.

──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Tomoki Yoshimura 3-4-1-10 Nihonbashi Honcho, Chuo-ku, Tokyo Investigator, Kaken Pharmaceutical Co., Ltd. Special Medicine Department Shoei Hoshino (56) References JP-A-62-45505 JP, A) JP-A-2-25405 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) A01N 47/28 A01N 43/76 CA (STN) REGISTRY (STN)

Claims (1)

(57) [Claims] (1) 3N- (2-fluoro-4-chloro-5)
-Cyclopentyloxyphenyl) -5-isopropylidene-1,3-oxazolidine-2,4-dione and 1- (2-chlorobenzyl) -3- (α, α-dimethylbenzyl) urea as active ingredients. Rice paddy herbicide composition characterized by the following