JPS59106406A - Disinfectant for seed - Google Patents

Abstract

PURPOSE:A disinfectant for seeds exhibiting excellent effect on unhulled rice infected with Gibberella fujikuroi of Bakane disease, resistant to agents, containing a mixture of one or more of benomyl, thiophanate-methyl, etc. and ammonium ethylenebis (dithiocarbamate). CONSTITUTION:A disinfectant containing a mixture of one or more selected from methyl 1-(n-butylcarbamoyl)-2-benzimidazolecarbamate (benomyl), methyl 2- benzimidazolecarbamate, 2-(4-thiazolyl) benzimidazole and 1,2-bis(3-methoxycarbonyl- 2-thioureido)benzene (thiophanate-methyl) and ammonium ethylenebis (dithiocarbamate) (amobam). The addition of amobam exhibits extremely high synergistic action, and shows specifically high seed disinfecting action. A blend of a mixed agent of benomyl, etc. and bis(dimethylthiocarbamoyl) disulfide and amobam also gives the same synergitstic effects.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides methyl 1-
(n-butylcarbamoyl)-2-benzimidazole carbamate (hereinafter referred to as benomyl), methyl 2-benzimidazole carbamate (hereinafter referred to as MBC),
2-(4-thiazolyl)benzimidazole (hereinafter TB
Z) and 1,2-bis(3-methoxycarbonyl-2-thioureido)benzene 11' thiophanate methyl), or any one of these compounds and bis(dimethylthiocarbamoyl) disulfide (hereinafter referred to as Regarding a seed disinfectant characterized by blending ammonium ethylenebis(dithiocarbamate) (hereinafter referred to as ambam) in a mixture with TMTD),
In particular, the present invention relates to a novel seed disinfectant that exhibits a remarkable effect on rice grains infected with drug-resistant bacteria, which is one of the major diseases of paddy rice.

C0NHC4) (9-and SS TMTD (CH3) YuNC95CN (C
:) 13) 2 Anham S 1 In recent years, rice cultivation methods have become more labor-saving, and the mechanical transplantation of young seedlings has become popular nationwide. 8. Since the box-raised cultivation method for mechanical transplantation of rice is cultivated under the high temperature and humidity conditions of dense sowing, various diseases such as rice seedling damping-off, limpus disease, and bacterial fungal rot occur frequently. In particular, the outbreak of rice baka seedling disease is caused by conventional water.
Since the number of insects increases significantly compared to the number of generations, seed sterilization is necessary to prevent insect control when raising mechanically transplanted young seedlings.

Conventionally, mercury agents have been widely used as seed disinfectants. However, production was discontinued due to its toxicity to human stock.

As an alternative seed disinfectant, rice seed disinfection using the invasive fungicides benomyl, thiophanate methyl, or a mixture of these and TMTD, which appeared in 1973, has become widespread nationwide, and currently 99% of the national market share is due to these agents. It is divined.

However, recently, seed disinfection using these chemicals has also caused
There are areas where the effects are less effective. The cause of this has been found to be the emergence of a rice fungus that is resistant to benomyl and thiophanate methyl. The emergence of such resistance to 1.71 is closely related to the establishment of the J(1: +Wi mechanical transplant cultivation method), which is popular nationwide as a labor-saving rice cultivation technique, and there is an urgent need for V pest control measures. The reality is that gender is being pointed out from all quarters.

In view of these current circumstances, the present inventors tested many compounds and conducted extensive research in order to develop a rice seed disinfectant that is effective against resistant bacteria-infected rice. As a result, it was found that by disinfecting seeds with the drug of the present invention, which is a combination of 2-tazole compounds or thiophanate methyl with Anovam, a high seed disinfection effect was shown on paddy infected with rice baka-nae disease, which is susceptible to these drugs. Of course, we have found that these drugs exhibit a high seed disinfection effect specifically on rice grains infected with I-resistant Oryza vulgaris, which cannot be expected with these drugs. Note: Ambum alone has almost no practical seed disinfection effect against the rice fungus that is sensitive to benomyl, MBC, TBZ, and thiophanate methyl, and against the rice fungus that is resistant to it. unacceptable. However, an extremely unexpected new fact was discovered that by mixing Ambum with benomyl, MBC, TBZ, or thiophanate methyl, specific synergistic seed disinfection against rice grains infected with resistant bacteria can be achieved.

The active ingredients of the present invention, Bearmil, MBC, TBZ, and thiophanate methyl, are widely used as agricultural fungicides for various diseases of vegetables and fruit trees, in addition to rice bactericide, and have a wide spectrum of control activity and are excellent in that they do not cause chemical damage. It is a drug.

These matters are described in Japanese Patent Publication No. 45-25720 (Benomyl), Japanese Patent Publication No. 11319-1972 (MBC), Publication No. 23274-1974 (TBZ), Japanese Patent Publication No. 45-11327 (TBZ),
No. 49078 (thiophanutomethyl), pages 190-191 (benomyl), pages 188-190 (thiophanate methyl) of the "Pesticide Handbook 1981 Edition" (published by the Japan Plant Protection Association, July 20, 1981), etc. It was written and completed in . However, as a result of continuous use of these chemicals, resistant bacteria have emerged in diseases such as powdery mildew on cucumbers, gray mold on various vegetables, apple scab, and Japanese kudzu blight, so are they considering countermeasures against these? This is the current situation. Among these compounds, benomyl and thiophanate methyl are easily converted in water or in plants,
Both will be on MBC. It is well known that MBC is the active substance of henomyl and naophanate methyl. Furthermore, TBZ is a compound having a penzimiguzole skeleton similar to benomyl and MBC, and its control activity spectrum is very similar to the other three compounds. Furthermore, it is a well-known fact that resistant bacteria that have developed due to the use of any of these four compounds cannot be controlled at all by spraying any of the other three agents, and that there is cross-resistance between the four compounds. It is. As mentioned above, Benomyl, MBC
, TBZ and thiophanate methyl are a group of compounds with very similar disease control properties.

- Power, Ampam is the above-mentioned “Pesticide hand dunk 1981
As described on page 142 of ``4W Edition'', it is an agricultural fungicide that is used as a foliar spray to treat tobacco rot, parabeta mildew, chrysanthemum white rust, etc. dJ has no activity when treated alone.

The present inventors achieved the objective by blending an/heme into one selected from benomyl, MBC, TBZ, and thiophanate methyl shown in L or a mixture of any one of these compounds and TMTD. They discovered a novel seed disinfectant that is highly effective against rice grains infected with rice bacillus-resistant bacteria, which leads to the completion of the present invention.

The seed disinfecting effect of the seed disinfectant of the present invention on rice grains infected with rice bacillus bacterium resistant bacteria is clarified by the following test examples.

In other words, when each of the active ingredients of the present invention is applied alone, it is almost ineffective against rice grains infected with resistant bacteria, and by combining it with Ambam, extremely high synergism is exhibited, and a high specific seed disinfection effect is exhibited. You can get completely unexpected effects. In addition, benomyl and thiophanate methyl are currently used as seed disinfectants in a mixture with TMTD, but even if Anhem is added to these mixtures, it has a synergistic effect similar to the above-mentioned two-line mixture. and exhibits a high seed disinfection effect.

The seed disinfectant of the present invention can be used by formulating it into a powder, wettable powder, emulsion, etc. together with the active ingredient, a carrier, and various auxiliary agents by a conventional method. The carrier used is clay,
141 carrier weight of talc, bentonite, kaolin, diatomaceous earth, silica, etc. or benzene, xylene,
Liquid carriers such as toluene, kerosene, alcohols (methanol, ethanol, isopropanol, n-butamel, etc.), ketones (acetone, methyl ethyl ketone, cyclohexanone), etc. are used.

A suitable surfactant and other auxiliary agents, such as stabilizers and spreading agents, may be added to these in appropriate amounts to form a formulation for use.

In the present invention, when using the active ingredients as a mixture, the weight ratio of the active ingredients is benomyl, MBC, TB.
It is appropriate to mix 0.5 to 2 parts of Ambam to 1 part of Z and thiophanate methyl. In addition, when used as a mixture of three types, benomyl, MBC, TB
0.1 to IIf of 7ampam to 1 part of Z or a mixture of 2 types of ophanate methyl and TMTD! It is preferable to mix them. However, it goes without saying that the blending ratio can be changed as appropriate depending on the conditions at the time of application and the occurrence of diseases. Further, the seed disinfectant of the present invention may be used by blending other fungicides, insecticides, herbicides, etc.

Next, examples of the present invention will be shown. In addition, all parts in the examples are parts by weight.

Tianshi Hangyu (hydrating agent) 20 parts of any one of henomyl, MEC, TBZ, and thiophanate methyl, ampam 20 parts, white carphone 15 parts, lauryl sulfate 3 parts, calcium lignin sulfonate 5 parts, and clay 37 parts Mix and thoroughly grind to obtain a wettable powder.

For wood irrigation, dilute 20 to 400 times with water and soak 1 part of the seed rice in a solution 1 to 2 times the volume of the seed rice for 48 hours, or add 0.1 to 1% royal water of the seed rice. Rice seedling disease can be controlled by thoroughly coating the seed rice with a hydrating powder.

Next, the disease control effect of the seed disinfectant of the present invention will be explained using test examples.

Core 1 - 2 Rice seeds tested for seed disinfection effect on rice blight-infected paddy Benomyl-resistant and sensitive rice baka-nae bacterium (Gibberalla fuji) cultured in steam-sterilized rice straw medium
Kuroi) is used as a spore suspension, and this is used as a spore suspension for flowering rice (
(variety Nipponbare) was spray inoculated twice separately,
Paddy infected with the rice fungus fungus (two types: paddy infected with a resistant bacterium and susceptible paddy) was obtained.

Seed-F Disinfection Method The seed rice to chemical solution ratio (v/v) was added to 6 dilutions of each drug at a predetermined concentration prepared according to the wettable powder of Example 1 using the rice grains infected with the rice bacterium obtained by the above method. The sample was immersed at 20° C. for 24 hours at a ratio of 1:1. The disinfection certificate is obtained after soaking the seeds in water at 20℃ for 3 days.
Germination treatment was carried out at °C for 24 hours.
5 g of dry seeds were sown per plot in a 80 cm' area. 32
After germination treatment at °C for 2 days, they were transferred to a glass room and cultivated. .

To investigate the disease outbreak, 30 days after sowing, the number of diseased bacteria that showed symptoms of rice baka seedling disease such as lengthening and withering was investigated, as well as the number of healthy bacteria (the total number of bacteria per IX was 350 on average). %〕
I asked for From this, as shown by the following formula, seed disinfection J- (%) was calculated in comparison with the diseased mycelium (%) of the untreated plot. Regarding phytotoxicity, we also observed germination rate and growth level.

Phytotoxicity Index O - No phytotoxicity 1 - Slight 2 2 High 3 - 4 - Fierce This test was carried out in two sections for ■ drug concentration, and the average seed disinfection rate (%) was determined. The results are shown in Table 1.

F continuation of the revised book Showa! December 5'7 90 Commissioner of the Japan Patent Office Kazuo Wakasugi 1, 11.1- Indication of patent application 3 filed on December 8, 1980, relationship with 11 amendments Patent applicant 5. The chemical formula S9 of benomyl in Column 6, "Detailed Description of the Invention" of the Specification, Contents of Amendment, Page 2 will be amended as follows.

Claims (1)

[Claims] +) Methyl l, -(n-butylcarbamoyl)-
2-Penzimitazole carbamate, methyl 2-
A mixture of two types of one selected from penzimitazole carbamate, 2-(4-thiazolyl)benzimidazole and 1,2-bis(3-methoxycarbonyl-2-thioureido)benzene and ammonium ethylenebis(dithiocarbamate) A seed disinfectant characterized by containing as a right-moving ingredient. 2) Methyl 1- (n-butylcarbamoyl)-
2-henzimidazole hemate, methyl 2-benzimidazole carbamate, one selected from 2-(4-thiazolyl)benzimidazole and 1,2-bis(3-methoxycarbonyl-2-thiourido)benzene, bis A seed disinfectant characterized by containing a 3-component mixture of (dimethylthiocarbamoyl) disulfide and ethylenebis(dithiocarbamide #)ammonium as an active ingredient.