JPS5827765B2 - Tansuiden Youjiyosouzai - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a herbicide for flooded fields containing 3,4-dichloropropionanilide (hereinafter referred to as DCPA), a specific carbamate compound, and a specific acid amide compound as active ingredients. .

DCPA is widely used as a herbicide for rice cultivation as a foliage treatment agent that does not cause any chemical damage to rice, and can control the major weeds of rice cultivation, Novieum, as well as young broad-leaved weeds.

However, the activity of this agent is significantly reduced in the presence of water, and its effectiveness is significantly reduced when the soil surface is moist.

Furthermore, under waterlogged conditions, it is difficult to exert any weed control effect.

Therefore, in order to use this chemical, it is necessary to first treat rice fields by dropping them into water, and then avoid rain for 2 to 3 days after treatment, which not only limits the timing of the treatment, but also requires extra labor for dropping and soaking into the water. shall be.

In order to solve these problems of CPA, the present inventor conducted various researches, discovered the unique effects of a specific carbame I compound and a specific acid amide compound, and completed the present invention.

The present invention relates to DCPA, β-naphthyl-N-methylcarbamate (hereinafter referred to as β-NAC) and 2-chloro-
This herbicide for flooded rice fields is characterized by containing 2/.6-ethyl-N(butoxymethyl)-acetanilide (hereinafter referred to as butachlor).

To use the herbicide of the present invention, 50 to 500 PCPA, preferably 100 to 400 PCPA per 10 are.
g, more preferably 150-4oO2, β-NAC 2-30g, preferably 5-20g, even more preferably 5-151, butachlor 25-4001, preferably 50-30o1, even more preferably 50-20010
Mix and use in proportion.

The agent of the present invention can be in an appropriate dosage form, such as an emulsion, an aqueous phase, or a granule, depending on the situation of use.

The formulation can be prepared by adding an inert carrier to each of the above-mentioned components, depending on the intended dosage form, and using common methods for formulating agricultural chemicals.

DCPA is said to be ineffective unless it is sprayed on the leaves and stems of plants.

The agent of the present invention can exhibit herbicidal activity even when applied to flooded field water, which is not possible with DCPA alone.

By further adding butachlor to the wetting agent of DCPA and β-NAC, a wide range of grass species can be quickly controlled with a smaller dosage, and the suppressive effect can be further sustained.

The present invention will be explained below by way of examples.

Example 1 Emulsion DCPA 20 parts (parts are parts by weight, the same applies hereinafter), βNAC 1
part, butachlor 10 parts, xylene 30 parts, cyclohexanone 29 parts and Tulpol (Toho Chemical Industry Trademark)
An emulsion was prepared by mixing and dissolving 10 parts of 800A.

Example 2 Water phase agent 30 parts of DCPA, part β-NACI, 15 parts of butachlor, 5 parts of white carbon, 44 parts of kaolin clay, and 5039.5 parts of Tsurpol were mixed and uniformly stirred to prepare a water phase agent.

Example 3 Granules: 9 parts of DCPA, 0.3 parts of β-NAC, 4 parts of butachlor, isostatic compound of kaolin clay and bentonite 81.
3 parts and 5 parts of calci**ium lignosulfonate were mixed and stirred, mixed with a small amount of water, made into granules using a granulator, and dried to prepare granules.

The present invention will be described in detail below by reference.

Test 1 Example 1 Transplant cultivation of young seedlings Fill a Wagner pot with a size of 1/5000 are and fill it with paddy soil.
Paddy soil containing wildflower seeds and various weed seeds was added to the surface layer, and after plowing, three 3-leaf rice seedlings (variety: Koshihikari) were transplanted with 2 plants each to produce 3 to 4 cr.
Novies grown and managed under flooded conditions of rL germinated and reached 3-3
．． When the plant reached the 5-leaf stage, a predetermined amount of the diluted solution of the emulsion of Example 1 with water was dripped with a pipette at 4 CrrL of water so as not to adhere to the stems and leaves of the plant.

Thereafter, the water was repeated at 4α during the test period.

On the 20th day after the treatment, the effects on each weed and the degree of damage to the paddy rice were observed, and the results are shown in Table 1.

In addition, the evaluation in the table was performed based on the following criteria.

10 Complete withering to 0 Harmless As is clear from Table 1, each single agent in the control plot has no practical effect in the treatment during the growing season of flooded paddy fields.

However, according to the present invention, the activity is significantly increased and all plant species are almost completely killed with a low dose, and no chemical damage to paddy rice is observed.

Test example 2 Filled with paddy soil in a Wagner pot of 1/5000 are for direct sowing cultivation.
After adding paddy soil containing seeds of various paddy weeds to the surface layer 3CrrL and plowing it, sow 30 pigeon-breasted germinated seeds of rice per pot 1 (variety: Koshihikari), submerged 1~
Growth was controlled at 2 cm.

When the wildflowers reached the 3.5-4 leaf stage and the rice reached the 3-3.5 leaf stage, a predetermined amount of the aqueous phase agent of Example 2 diluted with water was added to the buds of the plants. It was applied dropwise with a pipette so as not to touch the leaves.

On the 25th day after the treatment, observation and investigation were conducted according to the same evaluation criteria as in Test Example 1.

For comparison, a similar test was also conducted for a single drug.

The results are shown in Table 2.

As shown in Table 2, each single agent treatment shows almost no activity against paddy field weeds, including field weeds, even at high treatment rates.

In contrast, according to the present invention, the desired herbicidal effect can be achieved with a low dose, and weeds can be quickly and completely suppressed and killed.

In addition to this, no chemical damage is observed in rice.

Test 1 Test Example 3 Pack paddy soil into a 1/2,000 are Wagnerbot,
Add paddy soil containing seeds of various paddy field weeds, including grasshoppers, to the surface layer, and transplant 3 paddy rice seedlings (cultivar Ni Nihonbare) at the 25-3 leaf stage (cultivar Ni Nihonbare) with 1 * 2 trees after submersion and plowing. Then, the growth was managed in 3 to 4 cTL of water.

Flooding 4 for 2 hours when wildflowers have 2.5 to 3 leaves and 35 to 4 leaves.
A predetermined amount of Example 30 granules was treated with C7TL.

On the 30th day after the treatment, the fresh weight of the remaining plants was measured, and the herbicidal effect and herbicidal damage were expressed as the grass mass ratio according to the following formula.

Table 3 (Novie 2.5-3 leaf stage treatment) and Table 4 (
(3.5-4 leaf stage treatment).

As shown in Tables 3 and 4, the agent of the present invention is effective in controlling a wide range of weeds without causing any phytotoxicity to paddy rice.

Furthermore, although the weeds tended to regenerate in the control plot, the inventive agent completely killed the weeds and no subsequent regeneration was observed.

Claims (1)

[Claims] 13,4-dichloropropionanilide, β-naphthyl-
N~methyl carbamate and 2-chloro-/·6'-
A herbicide for use in flooded fields, characterized by containing diethyl-N-(7'')oxymethyl)acetanilide.