JPH0327521B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to a herbicidal composition. More specifically, α-(β-naphthoxy)propionanilide, N-(α,α-dimethylbenzyl)-α
-bromo-tert-butylacetamide and 2-
Chloro-2',6'-diethyl-N-(butoxymethyl)-acetanilide or 2-chloro-2',
The present invention relates to a herbicidal composition containing as an active ingredient any one of 6'-diethyl-N-(n-propoxyethyl)-acetanilide. [Prior art] Conventionally, herbicides for paddy fields in Japan have been broadly classified into three types based on the timing of use: early-stage, middle-stage, and late-stage herbicides, but the first two account for the majority of the amount used. Typical initial herbicides include 2,4,6-trichlorophenyl-4'-nitrophenyl ether and 2-chloro-2',6'-diethyl-N-(butoxymethyl). -acetanilide (hereinafter abbreviated as butachlor), and medium-term herbicides include S-ethyl-N,N-hexamethylenethiol carbamate and 2-methylthio 4,6-
Bis(ethylamino)-S-triazine and γ-(2
-Mixture with methyl-4-chlorophenoxy)butyric acid (hereinafter abbreviated as commercial product B), S-(4-chlorobenzyl)-N,N-diethylthiocarbamate and 2
-Methylthio-4,6-bis(ethylamino)-
Examples include a mixture of S-triazine and γ-(2-methyl-4-chlorophenoxy)butyric acid. However, among these herbicides, early stage herbicides are extremely effective when used at the beginning of weed emergence, but their effectiveness decreases significantly when used during the peak stage of weed emergence, while mid-stage herbicides are effective against weeds. Although it is effective from the beginning of emergence to the growing season, there is a problem in that using it during the germination stage causes significant phytotoxicity to paddy rice, and its use is limited to the period when the growth of paddy rice is considerably advanced. Furthermore, these herbicides are not sufficiently effective against perennial weeds, and often cause chemical damage or decrease in effectiveness depending on temperature and soil conditions. Recently, in order to save labor in agricultural work, there has been a desire for herbicides that can control all weeds in a single treatment and have a wide range of suitable periods, but as mentioned above, existing herbicides are There is no phytotoxicity to paddy rice throughout the period during which weeding is necessary, and which satisfies this requirement. [Problems to be Solved by the Invention] An object of the present invention is to overcome the drawbacks of the above-mentioned conventional techniques and to provide a herbicide for paddy rice that has excellent properties. In other words, the present invention can be safely used from the time before rice planting to any time after rice planting, has a wide herbicidal spectrum including perennials, has no chemical damage to rice, and has a sufficient herbicidal effect with a single application. The challenge is to provide a certain herbicide. [Means and effects for solving the problem] In order to solve the above problem, α-(β-naphthoxy)
As a result of intensive research on mixtures of propionanilide and various herbicides, the formula [] α-(β-naphthoxy)propionanilide represented by the formula [] N-(α,α-dimethylbenzyl)-α represented by
-Bromo-tert-butylacetamide and 2-chloro-2',6'-diethyl-N-(butoxymethyl)-acetanilide represented by the formula [], or a compound represented by the formula [], a compound represented by the formula [] A herbicide composition containing a compound represented by the formula [] and 2-chloro-2',6'-diethyl-N-(n-propoxyethyl)-acetanilide as an active ingredient. It has been found that the composition has properties that solve the above problems. All active compounds contained in the compositions of the invention are known. However, when each of these active compounds is used alone, the herbicidal activity is non-general-purpose and unsatisfactory, and the types of grass that can be controlled are limited. In other words, the compound represented by the formula []
46-14077, the compound represented by formula [] is disclosed in Japanese Patent Application No. 115588-1988, the compound represented by formula [] is disclosed in U.S. Patent No. 3442945, and the compound represented by formula [] is disclosed in Japanese Patent Application Publication No. 49-54527. , and are publicly known. The compound of formula [] is weakly effective against grass weeds, but highly effective against annual broad-leaved weeds, fireweed, and perennial weed. The compound represented by the formula [] is highly effective against weeds of the Cyperaceae family, ie, Cyperus japonica, Cyperus japonica, Cyperus japonica, and perennial Cyperus japonica. Compounds represented by formula [] or formula [] are highly effective against grass weeds, but are less effective against broad-leaved perennial grasses such as grasshoppers, and both compounds become somewhat less effective when the weeds reach advanced leaf stage. Common characteristics were observed. The present inventors have found that the composition of the present invention not only complements weeds that are difficult to control with individual active compounds, but also contains perennials at dosages that cannot be controlled by each agent alone due to the synergistic effect of the three active compounds. It was found to be effective against paddy field weeds. In other words, the effect is that it can be used against weeds such as Japanese grasshopper, Japanese cypress, annual broad-leaved weeds, and weeds such as Japanese grasshopper, Japanese cypress, Japanese cypress, Japanese cypress, Japanese parsley, Japanese parsley, etc. without any restrictions, and is extremely safe for rice. There was found. The present invention was completed based on these new findings. Although the herbicidal composition of the present invention exhibits a particularly strong synergistic effect at a certain composition ratio, the mixing ratio may be varied within a fairly wide range within a practical range. The weight ratio of the compounds represented by formulas [], [], and [] is 1:0.3 to 0.9:0.2 to 0.6, preferably 1:0.3 to
0.6:0.3-0.6 The weight ratio of the compounds represented by the formulas [], [], [] is preferably 1:0.3-0.9:0.1-0.3, preferably 1:0.3-0.6:0.1-0.3. The composition of the present invention is most effective when used in the form of granules, but it can also be formulated into powders, coarse powders, fine granules, wettable powders, flowables, and the like. When preparing the formulation, the active ingredients are increased in volume with mineral powders such as bentonite, clay, talc, and limestone, vegetable organic substances such as cellulose, synthetic or natural polymer compounds, waxes, or urea, and sodium lignin sulfonate, A method in which a surfactant such as polyvinyl alcohol or alkylbenzenesulfonic acid is added, mixed with water, granulated, and then dried.
Alternatively, it can be dissolved in a suitable solvent and uniformly adsorbed onto diatomaceous earth, vermiculite, etc. [Example] Next, examples of the present invention will be given, but the present invention is not limited to these. Compound [] is formula [], compound [] is formula [], compound []
represents the formula [], and the compound [] represents the compound represented by the formula []. Example 1 Granules 7 parts of compound [], 4 parts of compound [], 3.5 parts of compound [], 2 parts of sodium lignin sulfonate, and bentonite/talc (7/3)
After mixing 83.5 parts, add an appropriate amount of water and knead.
Granulate using a granulator to obtain 100 parts of the mixture. Example 2 Granules 7 parts of compound [], 3 parts of compound [], 3 parts of compound [], 2 parts of sodium lignin sulfonate, and bentonite/talc (7/3) 85
After mixing the two parts, add an appropriate amount of water, knead, and granulate using a granulator to obtain 100 parts of the mixture. The herbicidal effect of the composition of the present invention will be specifically explained below 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, and add 1 each of N, P ₂ O ₅ and K ₂ O to it.
Fertilize the entire layer with chemical fertilizer, add an appropriate amount of water, and stir thoroughly to create a hydrated state. Two paddy rice seedlings (leaf age 2/5) grown in advance in a greenhouse are combined into one
Seedlings were made into two seedlings per pot at a depth of 3 cm, and seeds of Japanese cabbage, Japanese cypress, Japanese cypress, Japanese firefly, and Helaomodaka were sown on these.
In addition, tubers of Japanese cypress, Japanese cypress, and overwintered buds of Japanese black bream were transplanted to the plants, and they were grown in a greenhouse while maintaining the sump water depth at 3 cm. 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 continued for 1 week at a rate of 2 cm/day. One month after the chemical treatment, the herbicidal effect and chemical damage to paddy rice were investigated, and the results are shown in Table 1. In this table, the herbicidal effect on each grass species is expressed using a 10-level numerical value from "0" to "9" according to the following guidelines, and the degree of chemical damage to paddy rice is indicated as "severe damage" or "major damage". , ``moderate harm,'' ``slight harm,'' ``slight harm,'' and ``harmless.''

【table】

【table】

【table】

[Table] Looking at the control effects at the beginning of weed germination, commercially available agents A and B are unable to control Urikawa, Mizugaya cyperus, and Omodaka. Compounds can control either one of Urikawa or Mizugaya spp., but they cannot control Omodaka at all. Compounds (++) or (＋＋
It is clear from Table 1 that the drug can control all plant species of Japanese millet grass, firefly, Japanese cypress, and Omodaka in amounts that cannot be controlled with a single agent, and there is no phytotoxicity to rice. Test Example 2 Weed control test during the weed growing season A concrete pot measuring 50 cm x 50 cm x 50 cm was filled with an appropriate amount of paddy soil containing seeds and tubers of annual and perennial weeds from paddy fields, and then N, P ₂ O were added to the pot. ₅ and 3 g each of K ₂ O were applied to the entire layer with chemical fertilizer to create a stagnant state. For this, leaf order 2.5
Two paddy rice seedlings were prepared per pot, and four plants per pot were transplanted at equal intervals. 10 days after rice planting, a predetermined amount of the test compound was treated in stagnant water using granules prepared according to the method shown in the above example. One month after the chemical treatment, the herbicidal effect in the pot and the chemical damage to paddy rice were investigated, and the results shown in Table 2 were obtained. During the test period, the depth of water in the concrete pot was kept at 3 cm, and water leakage equivalent to 1 cm ² per day was prevented.
It continued for several months. In the table, the classification of herbicidal effect and degree of chemical damage to paddy rice is the same as in Test Example 1.

[Table] From the results shown in Table 2, the herbicidal effect during the weed growth period was determined by the compound against Japanese millet grass, water cypress, and Omodaka, and by the compound against all tested plant species. It has almost no effect on , water snails, and omodaka. On the other hand, compound (++), compound (++
) is able to control all plant species of Japanese millet, firefly, urikawa, Japanese cypress, and Omodaka in amounts that cannot be controlled by each single agent, and it is clear that it is safe for rice. The synergistic effect brought about by the herbicidal composition of the present invention can be fully understood from the herbicidal effects shown in the above test examples, and will be explained in more detail below by selecting the common weed as a representative weed. The following method is usually used to test for interaction between any combination of three herbicides. (SRColby, Calculating Synergistic and
Antagonistic Responses of Herbicide
(See Combinations Weeds 15 , 20-22 (1973)) % damage when using a. E = Expected % damage when herbicides A, B, and C are mixed with P, q, and rg/a, respectively. E = X + Y + Z - (XY + XZ + YZ) / 100 + XYZ / 10000. . If the measured actual damage exceeds the calculated expected damage, this indicates that synergy exists in the herbicidal composition. The results of testing the interaction of the herbicide composition of the present invention are shown below using test examples. Test Example 3 Interaction Verification Test 1 kg of paddy soil is filled into an a/10000 pot, and 0.3 g each of N, P ₂ O ₅ and K ₂ O are applied to the entire layer with chemical fertilizers. After sowing a certain amount of germinated seeds of Helaomodaka and covering it with soil, an appropriate amount of water is gently added to create a stagnant state. When the Helaomodaka reaches the specified growth level,
A predetermined amount of the test compound was treated under stagnant water using a wettable powder prepared according to the method described in Example 2 above. 20 days after the treatment, the grasshoppers were pulled out, their air-dry weight was measured, and the damage was evaluated as % damage compared to the untreated control area. The results are shown in Table 3. In this table, the numbers for measured values and calculated values represent the following. 0%=No effect 100%=Complete death

【table】

〔Effect of the invention〕

As is clear from the above results, the composition of the present invention is harmless to rice even when used at any time from the beginning of weed germination to the peak of weed germination immediately after rice transplantation.
Furthermore, due to the synergistic effect of the three types of herbicides, all weeds can be controlled in a single application at a dose that cannot be controlled with each individual agent, which is preferable from the standpoint of environmental pollution, and is one of the most commonly used herbicides in the past. It is significantly superior to .

Claims (1)

[Claims] 1 α-(β-naphthoxy)propionanilide,
N-(α,α-dimethylbenzyl)-α-bromo-
tert-butylacetamide and 2-chloro-2',
6'-diethyl-N-(butoxymethyl)-acetanilide or 2-chloro-2',6'-diethyl-N
-(n-propoxyethyl)-acetanilide as an active ingredient. 2 α-(β-naphthoxy)propionanilide and N-(α,α-dimethylbenzyl)-α-bromo-tert-butylacetamide and 2-chloro-2′,
6'-diethyl-N-(butoxymethyl)-acetanilide in a weight ratio of 1:0.3 to 0.9:0.2 to 0.6. 3 α-(β-naphthoxy)propionanilide and N-(α,α-dimethylbenzyl)-α-bromo-tert-butylacetamide and 2-chloro-2′,
6'-diethyl-N-(n-propoxyethyl)-acetanilide in a weight ratio of 1:0.3 to 0.9:01 to 0.3.