JPS6028802B2 - Fungicide for agriculture and horticulture - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention contains kasugamycin or its salts and 2-(4-thiazolyl)penzimidazole (hereinafter referred to as "T") represented by the chemical structural formula below as active ingredients. This invention relates to an agricultural and horticultural fungicide characterized by the following.

Kasugamycin is an anti-symptomatic substance produced by the actinomycete named Streptomyces kasugamycin, and has a specific therapeutic effect against rice blast fungus, and has extremely low toxicity to humans, livestock, fish, and shellfish. In addition, it does not cause any chemical damage to rice, and is widely used as a safe rice blast control agent (Japanese Patent Publication No. 42-6818, Japanese Patent Publication No. 42-6818,
1-121757 and pages 33 to 3 of Iida Kakugai's ``Gendai Yakuza Kiza W'' (published by Asakura Shoten)).

However, kasugamycin has poor residual efficacy against rice blast, and also has poor preventive spraying effects. In addition, rice blast fungi that are resistant to kasugamycin have appeared, and the current situation is that the reduction in the rice blast control effect of single application of kasugamycin has become a problem. The present inventors took advantage of the advantages of kasugamycin or its salts, which are currently used as a representative example of safe agricultural chemicals, and
In addition, many compounds were tested in order to develop a practical fungicide that could compensate for the above-mentioned drawbacks.

As a result, Kasugamycin or its salts are already known bactericidal agents in Japanese Patent Publication No. 42-23274, etc.
It has been found that a new fungicide containing TBZ, which has been put into practical use as a fungicide for fruit trees, gardening, and seed disinfection, satisfactorily achieves the above objectives.
The agricultural and horticultural fungicide according to the present invention exhibits control activity not only against susceptible rice blast fungi but also against resistant rice blast fungi.

Therefore, it has an excellent spraying effect against rice blast, and it is also suitable for water surface application to rice grown in seedling boxes for mechanical transplantation of young seedlings, which has recently become widespread, and to rice after transplanting to Honda. It exhibits an outstanding pesticidal effect even in many cases.
Therefore, it can be effectively used in various treatment methods, especially as a rice blast control agent. In addition, it exhibits an outstanding control effect not only against rice blast, but also against tomato leaf mold, for example. Moreover, the control effect is more synergistic when mixed with TBZ than when Kasugama perilla or its salts are applied alone.
As shown in Test Example 3, it also has a long-term residual effect. The blending ratio of the active ingredients in the present invention is 1 part of kasugamycin or its salts to 1 part of T by weight.
A suitable proportion of BZ is 10 to 10 parts, but the proportion can be changed as appropriate depending on the conditions at the time of spraying and the status of disease occurrence.

When formulating the agricultural and horticultural fungicide of the present invention, various carriers and adjuvants used in conventional methods are added to form desired formulations such as powders, wettable powders, emulsions, fine granules, granules, and tablets. It can be in the form of

Next, examples of the present invention will be shown.

In the examples, parts refer to parts by weight. Example 1 Wettable powder Kasugamycin hydrochloride 1 part, TBZ 25 parts, diatom ±27
5 parts Solpol 8048 (trade name of emulsifier manufactured by Toho Chemical Co., Ltd.) and 2 parts Lunox 100 ratio (same)
A wettable powder is obtained by uniformly mixing and pulverizing 4 parts and 4 parts of clay.

Before or immediately after the outbreak of rice blast disease, dilute this hydrating powder with water to 500 to 100 parts, and spray it on the rice body using an appropriate spraying device at a rate of 100 to 150 parts per 10 are. By doing so, rice blast disease can be controlled.

In addition, for rice cultivated in box seedlings, if you apply 50% of this agent at a rate of 200 to 500M per box the day before transplanting to Honda, initial control of rice blast after transplanting will be achieved. be able to. Example 2 Powder Sugamycin hydrochloride 0.1 part, T 2 parts, talc 92
．． A powder agent is obtained by uniformly mixing and pulverizing $1 part and 5 parts of white carbon.

Spread this powder directly onto the rice plant using a suitable scattering device.
By spraying at a rate of 3 to 4 kg per area, rice blast can be controlled.

Example 3 Weigh out 0.5 parts of sugamycin hydrochloride, 5 parts of T-sulfonate, 3 parts of sodium lignin sulfonate, 2 parts of sodium lauryl sulfate, and 89.5 parts of clay, then add water and knead well. and granulate.

This is dried and separated into granules of 64 to 32 mesh. To control rice blast disease in the early stages after transplanting rice seedlings to Honda, apply this drug for 30 minutes per box to rice grown in box seedlings the day before transplanting to Honda (2. Maniwa stage of rice seedlings). Sprinkle grains directly at the rate of .

In addition, to control leaf blast and ear blast that occur in the middle stage after transplanting to Honda, this granule can be applied to the water surface at a rate of 3 to 4 k9 per 10 ares to prevent rice blast. It can be prevented. Next, the disease control effect of the agricultural and horticultural fungicide of the present invention will be explained using test examples.

Test Example 1 Rice blast control effect test (pot) The rice to be tested is a young seedling of the cultivar Aichi Asahi (4th hollyhock stage) cultivated in a clay pot with a diameter of 9 skins.

In addition, three strains of kasugamycin field-resistant bacteria, which were monospore-isolated from rice blast diseased panicles of general farmers' paddy fields in the Yamagata Fushonai region in 1970, were each placed on an oatmeal agar medium. Spore suspension (Olympus Microscope 15
A solid spore concentration of approximately 12 per field of view was used. This spore suspension was then used as an inoculation source for the disease bacteria and was spray inoculated onto the rice bodies. The inoculated pots were then kept at room temperature of 23-2500° C. for 1 day. The test chemicals were prepared by making a solution of a single wettable powder containing each active ingredient twice the final spray concentration with water, and adding equal amounts of the same.

Then, 3 hours after inoculating the disease bacteria, this solution was added to 1 pot per 7 pots.
It was evenly distributed using an automatic spray gun at a rate of 5:5. To investigate the disease onset, 7 days after inoculation, the number of rice blast spreading lesions was investigated on the top leaves at the time of inoculation (10 rice plants/pot, 3 pots/treatment), and the control value (%) was calculated using the following formula. did. Control value (%) = [-Sardine Heron Kiri Kaori Sewani Cloud Pus Osu Sardine] Side In addition, the presence or absence of chemical damage to rice was evaluated based on the following criteria.

Soil: Slight 10: Slight H: Medium …: Car Also, based on the control value of each single agent when used alone, the predicted effect (expected value) when mixed is calculated using the following formula, and the actual measurement is performed. Based on the comparison with the values (actual value/expected value), it was determined whether or not there was a synergistic effect based on the following evaluation criteria.

Expected value = pa 10 (100-pa) pb 100 Pa: Effect of single application of kasugamycin Pb: TB
Effect synergistic evaluation criteria for single application of Z Actual value/Expected value > 1: Synergistic effect actual value/Expected value = 1: Additive effect actual value/Expected value < 1: Comprehensive effect The result is the first As shown in the table.

Table 1 Note 1) IBP represents S-penzyl 0,0-diisopropyl phosphorothate, and organic sulfur nibble represents the chemical name dimethyl dichogalbamate nibble (trade name Sankel).

Note 2) The numbers in parentheses indicate the number of rice blast lesions per leaf in the non-sprayed area.

Test example 2 Rice blast control effect test (field seedling) Dried rice (variety: Sasanishiki) was soaked for 4 hours in a 20-diluted solution of Penrate T wettable powder 20 (commercially available seed disinfectant). After sterilization, the paddy that had been immersed and germinated was sown in rows in a field with the size of the first section (6 rows, 11 rows) according to the usual method.
Day).

Add the drug solution prepared in the same manner as in Test Example 1 at 1 dose per area.
It was sprayed three times (June 30th, 7th 5th, and July 9th) at a rate of 0.00% using a small moving sprayer. The rice blast bacteria tested were two types of kasugamycin-susceptible and resistant bacteria, which were obtained by monospore isolation from confirmed diseased panicles in the Shonai area of Yamagata Prefecture in 1971.
A spore suspension (spore concentration was the same as Test Example 1) was used as fresh spores of the bacterial species, with spores of kasugamycin-susceptible bacteria and spores of resistant bacteria mixed in a ratio of 3:7. Inoculation of the spore suspension was carried out twice per district, one day before the first chemical spraying (June 29th) and two days after the second chemical spraying (July 7th). 2
Around 0's, I made a Kirigura species. Then, the inoculated field seedlings were covered with pineal overnight to promote the onset of the disease. The disease onset investigation was carried out by investigating the ratio (%) of the dead area of rice blast lesions 21 days after the first inoculation, and calculating the control value (%) using the following formula:
I asked for This test was conducted using two lotuses per area per drug concentration, and the average control value (%) was calculated.

Further, in accordance with Test Example 1, the expected value of the actual measured value was determined, and the presence or absence of chemical damage to rice was observed. The result is the second
As shown in the table. Control value (%) = [1-Yabutai supervision fee pseudo agricultural separation] side Table 2 Note 1) EDDP is the chemical name ○-ethyl S, S-sophenylphospho.

Represents geoate. Note 2) The numbers in parentheses indicate the average rice blast disease spot dead area ratio (*) in non-sprayed plots. Test Example 3 Rice blast control effect test (seedling raising box) Seedling cultivation in a box in the same manner as Test Example 2 (seeding amount: 200 dry paddy seeds)
evening/box) 2. Rice seedlings in the Maniwa period (variety: Sasanishiki)
Then, the granules prepared according to Example 3 were sprinkled 30 times per box.

After applying the chemical, water was sprinkled at a rate of 200 per box. One day after drug application, 6 plants per plant (transplant spacing:
10) and was transplanted to Honda (June 20th). Honda transplant 2
The rice blast fungus spore suspension obtained in Test Example 2 was spray inoculated twice, 5 days later and 30 days later. The inoculated test plots were then covered with vinyl to encourage the onset of rice blast. The disease onset survey was carried out by measuring the ratio of the dead area of rice blast lesions on the upper three leaves 11 days after the second inoculation.
%) was investigated, and the control value (%) was calculated using the following formula.

Pest control value (%) = [-Kikuka outrage etc.
%) was calculated.

In addition, the presence or absence of chemical damage to rice was examined using the same criteria as in Test Example 1. The results are shown in Table 3. Third
Table Note 1) The numbers in parentheses indicate the average ratio of rice blast disease spot dead area on the top three leaves of the untreated plot.

Note 2) Cabtan has the chemical name N-(triclo).

Griseofulvin is an antibiotic. Test example 4 Tomato leaf mold control effect test (open field cultivation)
Tomato seedlings (variety: Yoneju) 30 days after sowing were planted according to the conventional method (row width 170 skin, plant spacing 45 cm, 2-row mallet).

Then, a hydrating agent containing a single active ingredient was added to the tomato seedlings in equal amounts to make a solution twice the final spraying concentration with water, and then the same amount was added to the tomato seedlings. Spraying was carried out at a rate of 200 sprays per day over three times on June 20th (first time), June 25th, and July 1st (the third time was 250 sprayers) using a shoulder-type semi-daily movable sprayer. The test plots were divided into 2 sections, 1 section and 1 vermilion, and the disease investigation was carried out on July 11th by randomly selecting 3 plants from 3 locations in each section and calculating the percentage of tomato leaf mold disease onset area (%) of each equidistant leaf on the node. ), and calculate the control value (%) using the following formula:
I asked for

In addition, the presence or absence of chemical damage to tomatoes was observed using the same criteria as in Test Example 1. Control value (%): [-Pseudo-nada age mother coagulation mist seaweed competition] The result is 4.

Table 4 Note 1) Soneb represents zinc ethylenepis(.dithocal'cuminate).

Claims (1)

[Claims] 1. An agricultural and horticultural fungicide characterized by containing kasugamycin or its salts and 2-(4-thiazolyl)benzimidazole as active ingredients.