JPS593443B2 - Herbicide composition for paddy fields - Google Patents

Description

[Detailed description of the invention] The present invention relates to general formula (I) represents.

However, X represents a hydrogen atom or a halogen atom.

) and 0,0-diisopropyl-8-(2-(benzenesulfonamido)ethyldithiophosphate) (hereinafter abbreviated as IPTP) as active ingredients. The present invention relates to a characteristic herbicide composition for paddy fields.

More specifically, by mixing the above-mentioned two components in an appropriate ratio, the usable period and herbicidal spectrum are significantly expanded compared to conventional paddy field herbicides. An object of the present invention is to provide an excellent herbicide composition that can be used at any time of the year and can also control perennial weeds that are difficult to control with conventional herbicides.

Herbicides for paddy fields in Japan are roughly divided into three categories based on the timing of use: early-season herbicides, mid-season herbicides, and late-season herbicides, and the first two account for the majority of the amount used.

The initial herbicide is MO (2,4,6-dolychlorophenyl-4'-nitrophenyl ether) Oyobi NLP (
2,4-dichlorophenyl-4'-nitrophenyl ether), and as a medium-term herbicide, Sweep M [methyl-N-(3,4-dichlorophenyl) carbamate and 2-methyl-4 -mixture with chlorophenoxyacetic acid ethyl ester], Saturn 5C8-(4-chlorobenzitree N-N-diethylthiol carba, 7'
-todo2-methylthio-4,6-bisethylamino-S
-) mixture with riazine], etc.

Early-acting herbicides are extremely effective when used at the beginning of weed emergence, but their effectiveness is significantly reduced when used at the peak of weed emergence.

Mid-season herbicides are effective from the beginning of weed germination to the growth stage, but when used during the germination stage, the damage to paddy rice is significant and the period of use is limited to the period when the growth of paddy rice is considerably advanced.

Furthermore, depending on the temperature and soil conditions, phytotoxicity may occur or the effectiveness may decrease.

moreover. These herbicides are not sufficiently effective against perennial weeds (in fact, they actually promote the growth of perennial weeds.

Recently, there has been a desire for herbicides that can control all weeds in a single treatment and have a wide range of application periods to save labor in agricultural work. There are no herbicides that cause harm to paddy rice throughout the entire growing period (and that satisfy this requirement).

α-(β-naphthoxy)propionic acid derivatives represented by the general formula [υ] are highly effective against annual broad-leaved and Cyperaceae weeds, and perennial weeds such as Prunus japonicus and Helaomodaka firefly.

On the other hand, although it is ineffective against grass weeds, it is extremely safe against paddy rice (and can be used at any time after transplanting).

In addition, IPTP is highly effective against barnyard grass, and has a remarkable effect on weeds of the Cyperaceae family, such as Cyperus japonicum, Cyperus spp. For paddy rice, there is some concern about chemical damage if treated in the early stages of transplantation.

The present inventors have conducted repeated research with the goal of developing a herbicide that can be used at any time from the onset of weeds immediately after rice planting to the growing season, and which exhibits an appropriate control effect and is harmless to paddy rice. , we have discovered that a mixture of the compound represented by the above general formula α] and IPTP in an appropriate ratio exhibits an extremely significant weed effect that exceeds expectations, and has no phytotoxicity to paddy rice at all. The invention has been completed.

In other words, a mixture of the compound represented by the general formula [[] and IPTP can be used in small doses that cannot be controlled by each component alone.
In addition to annual weeds such as Japanese barnyard grass, Japanese grasshopper, Japanese fireweed, Japanese grasshopper, and Japanese grasshopper, unexpectedly, it is also highly effective against perennial weeds such as Japanese grasshopper, Japanese cypress, and black porgy, which cannot be completely controlled by each individual species. (Test 5) or for paddy rice, it can be used with confidence throughout the growing period from before seedling transplantation without any concerns about phytotoxicity.

In addition, some herbicides for paddy rice have recently become a problem as they cause phytotoxicity to adjacent crops due to transpiration, and show severe growth suppression symptoms in paddy rice under reducing paddy fields in which herbal medicines have been plowed. However, the composition of the present invention has no effect on other crops due to transpiration, and there is no problem with the effect of differences in soil conditions.

Furthermore, in recent years, seedling box treatment with insecticides and fungicides has become widespread, and with this, there is concern about the chemical damage caused by initial herbicides to young paddy rice plants. Even in the case of application, no unfavorable effects on paddy rice are observed.

The dosage of the compound represented by the general formula [0] and IPTP, which are the active ingredients of the herbicidal composition of the present invention, can be significantly reduced compared to the dosage when each is used as a single agent. The ratio of IPTP to 1 part by weight of the general ring compound is preferably 0.2 to 8 parts by weight.

The above general formula CI) used in the herbicidal composition of the present invention
Specific examples of the compounds represented by are as follows.

The composition of the present invention is most effectively formulated into granules for use.

That is, the amount of the active ingredient is increased using bentonite, clay, talc, limestone, etc., a binder such as sodium ligninsulfonate, polyvinyl alcohol, or sodium alkylbenzenesulfonate is added, the mixture is kneaded with water, and the mixture is extruded and granulated, followed by drying. method, or dissolved in a suitable solvent,
It is most desirable to formulate it as a granule by uniformly adsorbing it on granular diatomaceous earth, vermiculite, or the like.

This granule is produced from the ground by hand or using a granulator.
Alternatively, the particles can be uniformly dispersed from the air using a helicopter.

In addition to granules, it may be formulated into an aqueous phase agent or powder, and may be diluted with water or sprayed directly.

Furthermore, if necessary, it is also possible to use them in combination with insecticides, fungicides, or other herbicides, or to formulate formulations.

Next, examples of the present invention will be given, but the present invention is not limited to these examples.

All mixing ratios in the examples indicate weight ratios.

Example 1 Granule Compound A 10 parts, IPTPIO part, bentonite 55 parts, talc 21 parts, dodecylbenzenesulfonate sodium 1 part
parts, 1 part of polyoxyethylene alkyl allyl ether,
After mixing and 2 parts of sodium ligninsulfonate, an appropriate amount of water is added and kneaded, followed by granulation using a granulator in a conventional manner to obtain 100 parts of granules.

Example 2 10 parts of granule compound B, 7 parts of IPTP, 50 parts of bentonite?
Talc 30 parts, alkylnaphthalene sulfonic acid condensate 2
1 part of dioctyl sulfosuccinate are mixed, an appropriate amount of water is added and kneaded, and the mixture is granulated using a granulator in a conventional manner to obtain 100 parts of granules.

Example 3 After mixing 08 parts of granule compound, 35 parts of bentonite, 49 parts of talc, 2 parts of sodium ligninsulfonate and 1 part of sodium dodecylbenzenesulfonate, an appropriate amount of water was added and kneaded, and the mixture was mixed using a granulator. granulate and dry in the usual manner.

This is impregnated with IPTPS to obtain 100 parts of granules.

Example 4 87 parts of granule compound, 12 parts of IPTP, 52 parts of bentonite,
26 parts of clay, sodium alkylbenzenesulfonate 2.
After uniformly pulverizing and mixing 5 parts and 0.5 parts of polyvinyl alcohol, an appropriate amount of water is added and kneaded, followed by granulation using a granulator in a conventional manner to obtain 100 parts of granules.

Example 5 9 parts of powder compound C, 87 parts of IPTPJ, and 87 parts of diatomaceous earth/clay mixture are mixed and ground to obtain 100 parts of powder.

Example 6 30 parts of water phase agent compound A, 20 parts of IPTP, 1 part of white carbon
0 parts, 35 parts of diatom, lignin sulfo Δ dredder 3
1 part and 2 parts of sodium dodecylbenzenesulfonate are mixed and ground to obtain 100 parts of an aqueous phase agent.

Hereinafter, the effects of the present invention will be specifically explained using test examples.

Test Example 1 Weed control test at the beginning of weed germination Fill an A/2000 Wagner pot with 11 kg of paddy soil, fertilize the entire layer with chemical fertilizers of N1P2O6 and Ni20, and mix thoroughly by adding an appropriate amount of water. Make it hydrated.

2 of paddy rice seedlings (leaf age 2.5) grown in advance in a greenhouse
One plant is used, and two plants are planted per pot at a depth of 3crfL, and this is followed by a Japanese cypress, a Japanese cypress, and a Japanese cypress.
I sowed seeds of firefly and Heraomodaka.

In addition, tubers of Urikawa, Japanese cypress, and Japanese black bream and overwintering buds of Japanese pine were transplanted to this, and the stagnation depth was increased to 3 cI.
The cells were grown in a greenhouse while being maintained at rL.

Three days after the seedlings were seeded, at the beginning of weed germination, a predetermined amount of the test compound was treated using granules prepared according to the method shown in the above example.

After treatment, water leakage was given at lCr/L/day.

One month after the chemical treatment, the amount of remaining weeds and the chemical damage to the paddy rice were investigated, and the results are shown in Table 1.

In this table, the degree of chemical damage to paddy rice is classified into six levels: ``Serious damage'', ``Daikichi'', ``Medium Yoshi'', ``Shosho'', ``Slight harm'', and ``Harmless''.

Test Example 2 Weeding test during the weed growing season A suitable amount of paddy soil containing seeds and tubers of annual and perennial weeds from paddy fields was poured into a concrete pot of size 50crrL x 50crrL x 50crrL, and
The entire layer was fertilized with 3 y each of N, P2O, and K20 using chemical fertilizers to create a stagnant state.

Two paddy rice seedlings at leaf age 2.5 were transplanted to each pot, with four plants per pot at equal intervals.

17 days after rice planting, a predetermined amount of the test compound was treated under stagnant water using granules prepared according to the method shown in the above example.

One month after the chemical treatment, the amount of weeds remaining in the pot and the chemical damage to paddy rice were investigated, and the results shown in Table 2 were obtained.

The depth of water in the concrete pot during the test period was 3.
Maintain cIrL and prevent water leakage equivalent to 1 crrL per day.
It lasted for several months.

Test Example 3: Field test A paddy field in which common weeds naturally coexist was plowed, fertilized (N, P2O, K20 each IIw/a), puddling, and leveled using the usual methods. 2,57r
Two paddy rice seedlings of leaf age 2.5 were transplanted into this with a furrow spacing of 30 m and a plant spacing of 15 crfL.

After transplanting, while keeping the water depth at 3 to 5 crIL, weed germination start period (3 days after rice planting) and the rice millet at 3.0 to 3.0 cr IL.
．． At the 5th leaf stage (15 days after rice planting), a mixture or single granule of the test compound prepared according to the method shown in the above example was spread by hand.

In addition, commercially available MO granules-9 and Saturn S granules were tested as control drugs.

The amount of weeds one month after spraying and the yield of paddy rice four months after spraying were investigated, and the results shown in Table 3 were obtained.

The following method is used to test for interaction when two types of herbicides are used together.

(Refer to Hideo Chinari, “Interaction test of mixed herbicides using equal effect line method,” Weed Research U, 16-20 (1973)) The dosage of herbicides A and B that produces an effect of P% when used alone is m , n.

When a mixture of both drugs C produces the same P% effect, the difference between the drug amount XA of drug A and the drug amount XB of drug B is equal to the P% in the additive effect of the drugs if both drugs have an additive effect. It is called the effect line.

Using this line of additive action as a reference, if the iso-effect line is below (it indicates a synergistic effect, if it is above it indicates an antagonistic effect (see Figure 1)) Next, the herbicide composition of the present invention (Compound B [P E ) is shown as an example.

The growth inhibition rate for each plot was determined from the measured values of the air-dried type of Helaomodaka, using the untreated plot as a standard, and was organized as shown in Table 4.

Based on this table, the drug dose that provides 90% inhibition was plotted on a diagram as shown in Figure 2, and an isoeffect line for 90% inhibition was obtained.

As is clear from Fig. 2, the iso-effect line for 90% inhibition of the growth of Helaopoda in the mixed treatment of Compound B and MNPE is below the interaction line, indicating that the mixed use of both drugs exhibits a synergistic effect. is clear.

Test Example 4 Interaction test using isoeffect line method 1 kg of paddy soil was filled into an a/10000 pot, and N, P2O5 and 20% each were added at 0,3? Fertilize the entire layer with chemical fertilizer.

After sowing a certain amount of germinated seeds of Helaomodaka and covering it with soil, an appropriate amount of water is gently added to make it hydrated.

When the Helaomodaca reached a predetermined growth level, a predetermined amount of the test compound was treated under sparging using an aqueous phase agent prepared according to the method described in Example 5 above.

After 20 days from the treatment, the Helaomodaka was taken out and the air-dried type was measured to determine the growth inhibition rate.

As is clear from the above results, the composition of the present invention is harmless to paddy rice even when used at any time from the beginning of weed germination to the peak of weed growth immediately after rice transplantation, and moreover, the composition of the present invention is harmless to paddy rice. Due to its powerful effect, it is possible to control all weeds in one application using a small dose that cannot be controlled with individual chemicals, which is preferable from the standpoint of environmental pollution, and is significantly superior to many conventionally used herbicides. (See Figure 2).

Test Example 5 Weeding test against perennial weeds 11 kg of paddy soil is filled into an A/2000 Wagner pot, and the entire layer is fertilized with 12 each of N1P2O5 and Ni20 to make it watered.

Two paddy rice seedlings with a leaf age of 2.5 were transplanted into each pot, and tubers of Urikawa, Omodaka, Nimizugaya Tsuri, and Kurogwai were also transplanted, and the water depth was increased to 3crI.
The plants were grown outdoors while being kept at L.

Five days later, at the beginning of weed emergence, the seedlings were treated with a predetermined amount of the test compound using granules prepared according to the method shown in the above example.

After treatment, water leakage of ICrrLZ days was given for 5 days.

One month after the chemical treatment, the amount of remaining miscellaneous grains and chemical damage to paddy rice were investigated, and the results are shown in Table 5.

[Brief explanation of drawings]

FIG. 1 is an iso-effect diagram of the effect p% in the additive action of Agents A and B, and FIG. 2 is an iso-effect diagram of 90% inhibition of Helaomoda growth in the mixed treatment of IPTP and Compound B.

Claims (1)

[Claims] 1 Represents the general formula I). However, X represents a hydrogen atom or a halogen atom. ) A herbicide for rice fields characterized by containing an α-(β-naphthoxy)propionic acid derivative represented by ) and 0,0-diisopropyl-8-(2-(benzenesulfonamido)ethyldithiophosphate) as active ingredients. Composition.