JPS61189205A - Seed disinfectant - Google Patents

Abstract

PURPOSE:A seed disinfectant that contains, as active ingredients, 2-bromo-2- bromomethylglutaronitrile and dichlofluanid, thus showing outstanding effect on rice plant BAKANAE disease, which is difficult to control, because strains resistant to chemicals have appeared and further against rice plant Helminthosporium leaf spot. CONSTITUTION:The objective seed disinfectant contains, as active ingredients, the compound of formula I (BBMG) and the compound of formula II (dichlofluanid). The resultant disinfectant is active on a variety of crops such as rice plant, wheat, barley, vegetables and others, especially in disinfection of rice seeds. The combination manifests high activity which cannot be attained only by a single component and their synergism can completely control the BAKANAE causative microorganisms both resistant and sensitive to benomyl and thiofanate, further shows good seed disinfection against rice plant Helminthosporium leaf spot. The formulation of individual ingredients may be varied according to application conditions,however, it is preferred that 0.5-3.0pts.wt. of dichlofluanid are used, per 1pt.wt. of BBMG.

Description

Detailed Description of the Invention The present invention disinfects the seeds of various crops such as rice, wheat, and vegetables before sowing to kill harmful plant pathogens that parasitize the seeds, or disinfect seeds that live in the soil after sowing. The present invention relates to a novel mixed seed disinfectant that can grow healthy seedlings and increase the yield of various crops by protecting seeds from soil-borne pathogens that invade and cause damage to young seedlings. More specifically, the present invention relates to 2-bromo-2-bromomethylglutaronitrile (2-bromo-2-bromomethylglutaronitrile (
A seed disinfectant characterized by containing N-(dichlorofluoromethylthio)-N',N'-dimethyl-N-phenylsulfamide (hereinafter referred to as dichlorofluanid) as active ingredients. Regarding. Therefore, the present invention can be effectively used in the agrochemical manufacturing industry and the agricultural and horticultural fields.

BBMG, which is one of the active ingredients of the present invention, can be used as a paint, as described in U.S. Pat. No. 3,833,731.
It is a well-known compound that is used as an industrial preservative and fungicide for wood, fibers, cosmetics, leather, coatings, latex emulsions, cutting oils, and other industrial applications. However, it has not been used as an agricultural seed disinfectant.

On the other hand, dichlorofluanid is known as an agricultural fungicide and is used as a spray agent to control gray mold, downy mildew, etc. on various vegetables. This is described in pages 185-186 of "Pesticide Handbook 1981 Edition J (Japan Plant Protection Association, published July 2011, 1981).

In addition, as a mixture containing dichlorofluanid, JP-A No. 5
7-16805 (a mixture of dichlofluanid and procymidone) is known, but a mixture with BBMG and its use as a seed disinfectant are not known (chemical names in parentheses). is a compound described in "Pesticide Bread 1 Nibuk 1981 Edition").

IXI, which 3-1 is trying to decide
A mixture consisting of D is widely used (the drug name is a common name listed in the ``Pesticide Handbook 1981 Edition'').

However, as a result of continuous use of these drugs for many years, drug-resistant bacteria have developed in Inabaka 1'l\\ disease, resulting in a decrease in control effectiveness. However, there is currently no effective alternative to these drugs, and it has been pointed out that there is an urgent need for control measures.

In view of these circumstances, it is an object of the present invention to provide a novel mixed seed disinfectant that is particularly effective against rice blight, which is difficult to control due to the emergence of drug-resistant bacteria, and is also effective against rice and sesame leaf blight. It is in.

In order to achieve the above object, the present inventors have intensively studied a large number of drugs. As a result, it was found that a mixture of BBMG and dichlofluanid was suitable for the purpose and exhibited an extremely high seed disinfection effect.

The seed disinfectant of the present invention is effective in disinfecting seeds of various crops such as rice, wheat, and vegetables, and is particularly effective in disinfecting seeds of rice. Shows excellent efficacy against rice blight seedling disease. Preferred disinfection methods include diluting the seed disinfectant of the present invention with water and immersing the rice seeds in this chemical solution, or coating the rice seeds with a powdered hydrating agent as is. In this case, in the former method, the rice seeds may be immersed in a low-temperature chemical solution for a long time (6 to 48 hours) or in a high concentration chemical solution for a short time (10 to 30 minutes). If the seed disinfectant of the present invention is used by these methods,
against benomyl, thiophanate methyl, and MBC (methyl-2-benzihedazole cica-octamate) and TBZ (2-(4-thiazolyl)benzimidazole), which have similar effects. Words that indicate a high seed disinfection effect
Of course, these agents or known mixed seed disinfectants containing one of these (e.g. Benomyl and TMTD)
It also shows a high specific control effect on rice grains infected with resistant bacteria, where the practical seed disinfection effect cannot be sufficiently exerted with the mixture of It is noteworthy that, as shown in the test examples below, although BBMG or dichlofluanid alone has no practical seed disinfection effect, by mixing the two, specific It has a synergistic effect on benomyl, thiophanate methyl, and can completely control both resistant and susceptible rice blight.

Furthermore, it exhibits an excellent seed disinfection effect against paddy infected with Sesame leaf blight, which is a major seed-borne disease of rice, similar to Inabaka Nae disease. The effect was exhibited as a synergistic effect that could not be obtained by using the two drugs alone, as in the case of Inakanae disease.

3-Hi no m-- The seed disinfectant of the present invention can be formulated into a wettable powder, emulsion, flowable, etc. by a conventional method together with the active ingredient, a carrier, and various auxiliary agents. Used 1]! As a body,
For solids such as clay, talc, Ben I, Nai I, kaolin, silica! body or benzene,
Liquid carriers such as cylene, toluene, kerosene, alcohols (methanol, ethanol, isopropanol, n-butanol, etc.), ketones (acetin, methyl ethyl ketone, cyclohexanone, etc.) are used. These can be formulated with appropriate amounts of surfactants and other auxiliary agents, such as stabilizers and spreading agents, for use. The blending ratio of the active ingredients in the present invention is B in terms of weight ratio.
For 1 part of BMG, add 0.5 to 3.
It is appropriate to mix it in a ratio of 0 parts. However, the blending ratio can be changed as appropriate depending on the conditions at the time of application. Furthermore, it may be mixed with any one of benomyl, MBC, TBZ, or thiophylnate methyl, which are widely used as seed disinfectants. Furthermore, other fungicides, insecticides, herbicides, plant growth regulators, etc. can also be mixed and used.

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

~ Sea l (1 BBMG 10 parts, dichlorofluanid 20 parts, white carbon 10 parts, lauryl sulfate I 3 parts,
2 parts calcium ligninsulfonate and 5 parts clay
Mix 5 parts, grind thoroughly, and use a hydrating agent? 4 Iru.

! -7'2(-1) 20 parts of BBMG, 20 parts of dichlorofluanid, Why i
- 15 parts of carbon, 3 parts of polyoxyethylene alkylaryl ether, 2 parts of I.lium lignin sulfonate, and 40 parts of clay are mixed and thoroughly ground to obtain a wettable powder.

The hydrating agent of the above example was diluted 10-1000 times with water, and the rice seeds were placed in a solution 1-2 times the volume of the rice seed container for 10 minutes to 48 hours.
Seed-borne diseases such as Inakanae disease can be controlled by soaking the rice for a period of time or by thoroughly coating the rice seed with a hydrating agent equivalent to 0.1 to 1.0% by weight of the rice seed.

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

Benomyl-resistant and susceptible Inabakinae disease fungus (Kiberella fujikuroi: Gib) cultured in steam-sterilized rice straw medium
berella fujikuroi) was used as a spore suspension to spray inoculate rice (variety: Nipponbare) at the flowering stage twice each. I tried it.

Seed yosho] [method immersion treatment method: Using the infected state of the rice bacterium bacterium obtained by the above method, the rice seed to drug liquid ratio (v /v) at a ratio of l'Ml to 2
Immersion treatment was carried out at 0°C. In this case, as with conventional seed disinfection methods, after soaking seeds in a low-concentration chemical solution for a long time (24 hours) and in a high-concentration chemical solution for a short time (10 minutes), the seeds should be lightly drained. It was placed in a plastic bag and coated uniformly with 0.25 to 0.5% of a seed-type drug.

The seed rice treated by the reprocessing method was air-dried at room temperature for about 3 hours after treatment, and then tap water was added to it at a ratio of 1:2 (v/v) to the seed rice and kept at 20℃ for 3 days (low concentration for a long time). immersion treated)
The seeds were soaked for 4 days (high concentration short time immersion treatment, wet powder surface treatment). Thereafter, the seeds were subjected to 24-hour bud treatment at 30°C, and 5 g per plot was sown on Kumiai granular medium ± (1 plot: 180 cm). After budding treatment at 32°C for 2 days, they were transferred to a glass greenhouse and cultivated.

:LLLIE: 30 days after sowing, investigate the number of infected plants and healthy bacteria that showed symptoms of rice baka seedling disease such as elongation and withering (
The total number of seedlings per area was approximately 200), and the diseased seedling rate (%) was determined. From this, the seed disinfection rate (%) was calculated in comparison with the diseased seedling rate in the untreated plot, as shown by the following formula. In addition, regarding chemical damage, we observed germination rate, growth level, etc.
It was expressed using the chemical toxicity index shown below.

Number of disease-causing bacteria, rate of diseased seedlings (%) = -X I OO Total number of surveyed seedlings, treatment area, diseased seedlings, seed disinfection rate (%) = (1-) Rate of diseased seedlings, untreated area x 100 Plant damage index - O: No drug damage l ：Low 2：Medium 3：High 4：Jinmoto test was conducted in 1 treatment and 3 plots, and the average seed disinfection rate (%)
I asked for The results are shown in Table 1.

Table 1 Note 1) The numbers in parentheses indicate the diseased seedling rate (%) in the untreated area.

Note 2) Commercially available seed disinfectant (product name Benlate T hydrating agent 2)
0).

Naturally infected paddy collected from fields where rice sesame leaf blight was common (
Variety: Golden Hagi) was used.

The test was carried out in exactly the same manner as the 11U ox test example 1, the rice blight seed disinfection test.

The disease onset investigation was conducted 20 days after sowing, and the number of diseased bacteria showing rice and sesame leaf blight symptoms and the number of healthy bacteria were determined. This test was conducted using a 1-treatment, 3-section system, and the diseased seedling rate (%) was determined in the same manner as Test Example 1, and the seed disinfection rate (%) was calculated from this. In addition, drug damage was investigated in the same manner as in Test Example 1.

The results are shown in Table 2.

Table 2

Claims (1)

[Claims] 2-bromo-2-bromomethylglutaronitrile and N-
A seed disinfectant characterized by containing a mixture of two types of (dichlorofluoromethylthio)-N',N'-dimethyl-N-phenylsulfamide as an active ingredient.