JPS5942644B2 - Fungicide for agriculture and horticulture - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is based on the general formula (wherein R is H,2-CI, 4-CH3,4-N
Represents O2.

This invention relates to an agricultural and horticultural fungicide characterized by containing N-substituted penzoyl-N'-1-lychloroethylidenehydrazine as an active ingredient as shown in Table 4 below.

The present inventors have conducted extensive research to develop new agricultural and horticultural fungicides, and have found that the compound represented by the above general formula exhibits a wide range of antibacterial spectrum against various plant pathogens, and is particularly effective against rice blast disease. , cucumber powdery mildew, cucumber blight, tomato late blight, cucumber gray mold, kidney bean sclerotium, and wheat rot.The present invention has been completed based on this finding.

In addition, the compound of the present invention not only does not contain heavy metals, which have recently become a problem in terms of toxicity to humans and animals, but also has long-lasting effects.
No phytotoxicity to plants is observed, and it has excellent properties for controlling a wide range of plant diseases.

The compounds according to the present invention are all known compounds, and N-benzoyl-N'-1-IJ chloroethylidenehydrazine is published in Pharmaceutical Journal 85 (3), 181 (1965).
It is described in.

Also, N-2-chlorobensyyl-N'-trichloroethylidenehydrazine is described in Chem, Absts, 47
．． Chem, Absts, 67.
Both are described in 73299x.

However, all of these treat reactions, and do not mention at all their bactericidal action as agricultural and horticultural fungicides, and the bactericidal action was discovered by the present inventors.

Next, the structural formulas and melting points of the compounds of the present invention are shown in Table 1.

(However, R is as described above.) That is, the target compound can be easily synthesized by heating and refluxing the corresponding acid hydrazide and chloral in a benzene solution for 1 to 3 hours.

Next, a typical synthesis example of the above compound will be shown below, taking Compound No. 1 as an example.

Synthesis Example I Synthesis of N-benzoyl-N'-(2,2,2-trichloroenalidene)hydrazine (Compound No. 1) 10 g (0,073 mol) of pensoylhydrazine was mixed with 200 mb of benzene, and chloral 18 , :l
(0,124 mol) was added dropwise.

Thereafter, the mixture was heated and stirred for 3 hours under reflux, and after cooling, the precipitated crystals were filtered and thoroughly washed with benzene.
19 g (quantitative) of pale brown crystals of decomposition) were obtained.

This was recrystallized from ethyl alcohol, with a melting point of 194-5.
Compound No. 1 at ℃ (decomposition) is 9.9 (
45%).

These compounds may be used as is or with a carrier (diluent).
It can be advantageously used in the form of powder, emulsion, liquid, etc. by mixing with

It is of course possible to ensure the effectiveness of the agricultural and horticultural disease control agent of the present invention by adding auxiliary agents such as spreading agents, emulsifiers, wetting agents, and fixing agents as necessary.

In addition, even when mixed with other chemicals, there is no risk of decomposition or deterioration of the drug itself, and there is no risk of deterioration of the other chemicals, so it can be used in combination or in combination with other fungicides, insecticides, fertilizers, etc. You can also do that.

Next, some examples will be given, but the carrier (diluent), the auxiliary agent, the mixing ratio thereof, and the active ingredient can be varied within a wide range.

Example l.

Powder Compound No. 1 3 parts - 40 parts 57 parts are mixed and ground, and used by sprinkling.

Example 2. .

irrigation agent Compound number 2 50 parts polyoxyethylene Alkyl allyl ether 6 parts Diatomaceous earth 44 parts Mix and grind to make a wettable powder, dilute with water, and use.

Finally, biological test examples showing the excellent bactericidal efficacy of the compounds of the present invention are listed below.

Test example 1゜Pot test Q Koyoru rice blast control effect test diameter 10C1
An irrigation agent as in Example 2 was diluted and suspended in water at a predetermined concentration on paddy rice seedlings (variety: Sasanishiki) at the four-leaf stage grown in 'rL clay pots, and sprayed so that the leaves were sufficiently wet.

After the leaves have dried, a spore suspension of rice blast fungus is spray inoculated.
The conditions were kept at 27-28°C and high humidity.

Four days after inoculation, the number of lesions was investigated on the top 1 leaf/plant, 20 plants/pot, and 3 pots/treatment, and the suppression rate was calculated using a linear equation.

Suppression rate (%) of total number of lesions in treated area - (1 - total number of lesions in untreated area) XI-00 results are shown in Table 2.

Test Example 2゜Cucumber Powdery Mildew Control Effect Test Cucumbers at the second true leaf stage (variety: Aigoku Hanshiro, 1 plant/pot, 3 pots/treated area used) grown using an unglazed body with a diameter of 10c1rL, An irrigation agent as in Example 2 was diluted and suspended in water to a predetermined concentration and then sprayed.

After the sprayed leaves had dried, spores were sprinkled on the diseased leaves with a brush to inoculate them, and the disease was caused to develop in a plastic greenhouse.

7 days after inoculation (according to the following investigation criteria), the disease severity was investigated for 1 leaf/pot and 3 pots/treatment, and expressed as the average disease severity per leaf.

The results are shown in Table 3.

(Survey criteria) Disease severity Disease severity 0 No symptoms 0.5 Diseases with an area ratio of 10% or less of the inoculated leaves ■ Diseases with an area ratio of 10 to 20% of the inoculated leaves 2 Infection with an area rate of 20-40% 3 Infection with an area rate of 40-60% on inoculated leaves 4 Infection with an area rate of 60-80% on inoculated leaves 5 Infection with an area rate of 80% on inoculated leaves Test example of the above symptoms: 3゜Cucumber downy mildew control effect test 1 test Cucumber leaves at the second true leaf stage grown using unglazed ceramics with a diameter of 10 cm (variety: Aigoku Hanshiro, 1 seed sown/pot) , 3 pots/treatment area), Example 2. A hydrating agent such as the following was diluted and suspended in water to a predetermined concentration and then sprayed.

After spraying and drying the leaves, the spore liquid of cucumber downy mildew collected from the diseased leaves was spray inoculated, kept at 22-23° C. and high humidity for 24 hours, and then left in a greenhouse.

Five days after inoculation, Test Example 2. The disease severity was investigated for 1 leaf/pot and 3 pots/treatment according to the same investigation criteria as above, and the disease severity was expressed as the average disease severity per leaf.

The results are shown in Table 4. Test Example 4゜ Tomato Phytophthora Control Effect Test Example 2 was applied to tomato seedlings at the 4-leaf stage (variety: Fukuju No. 2, 1 plant/pot, 3 pots/treated area used) grown using an unglazed ceramic body with a diameter of 10 CIrL. ．． An irrigation agent such as the following was diluted and suspended in water to a predetermined concentration and then sprayed.

After drying the sprayed leaves, a suspension of Phytophthora spores previously cultured on potato tubers was spray inoculated onto the tomato leaves sprayed with the chemical, and after being kept in a greenhouse at 20-22°C for 2 days, the leaves were left in a greenhouse.

Test Example 2 4 days after inoculation. The diseased lesions were investigated using the same research criteria as the above, and expressed as the average degree of disease per tree.

The results are shown in Table 5.

Test example 5゜ Cucumber gray mold control effect test Cucumber leaves at the second true leaf stage grown using clay pots with a diameter of 10 CrI'L (variety: Aigoku Hanshiro, 1 sown/pot, 3 pots/
Example 2. A hydrating agent such as the following was diluted and suspended in water to a predetermined concentration and then sprayed.

After drying the sprayed leaves, a circular section (diameter 5 mm) of agar containing gray mold fungus, which had been cultured in advance at 20°C for 5 days using a potato decoction agar medium containing sucrose, was placed at approximately the center of the cucumber leaf on which the chemical solution had been sprayed. 5 days after inoculation.
After keeping the plants in a greenhouse at 22 to 23°C for days, the degree of disease onset was investigated according to the following investigation criteria and expressed as an average disease severity.

The results are shown in Table 6. (Survey criteria) Disease severity Disease severity: 0 No symptoms: 0.5 Diseases occur only directly under or around the inoculated agar piece 1 Diseases occur on less than 20% of the area of inoculated leaves 2
Infection with an area ratio of 20 to 40% on inoculated leaves 3 Infection with an area ratio of 40 to 60% on inoculated leaves 4 Infection with an area ratio of 60 to 80% on inoculated leaves 5 Area ratio of inoculated leaves Example 2: 6° Green Bean Sclerotinia Disease Control Effect Test Example 2. An irrigation agent such as the following was diluted and suspended in water to a predetermined concentration and then sprayed.

After the sprayed leaves had dried, a circular section (diameter 5m711) of agar containing Sclerotinia fungi, which had been cultured for 5 days at 20°C on a potato decoction agar medium containing sucrose, was placed approximately at the center of the erect kidney bean leaf that had been sprayed with the chemical solution. Test Example 5. The degree of morbidity was calculated using the same survey criteria and expressed as the average degree of morbidity.

(Using 4 leaves per treatment area) The results are shown in Table 7.

Test Example 7 Wheat rot disease control effect test Wheat seedlings at the third true leaf stage (variety: Norin No. 64, 16 plants/pot) grown using clay pots with a diameter of 10 cm 1'IL were subjected to water use as in Example 2. The agent was diluted with water to a predetermined concentration, suspended, and sprayed.

After drying the sprayed leaves, a spore solution of the wheat rot fungus collected from the diseased leaves was spray inoculated and kept under high humidity conditions at 20 to 25°C for 24 hours.

Thereafter, the plants were left in a glass greenhouse, and after 7 days, the disease severity of 10 plants was investigated using the following survey criteria, and the disease severity was expressed as an average disease severity of 1.1 per leaf.

The results are shown in Table 8. (Survey criteria) Morbidity Degree of morbidity 0 No disease 0.5 Lesion area rate 5% or less 1 Lesion area rate 5-10% 2 Lesion area rate 10-30% 3 Test example for cases with lesion area of 30% or more 8゜ Antibacterial test against various plant pathogens The compound of the present invention was added to a potato sugar agar medium to a final concentration of 50,10100 pp, and after solidification, A spore suspension of various plant-pathogenic fungi was applied and inoculated onto the top.

After culturing at 28°C for 4 days, the presence or absence of bacterial growth was investigated.

(Test compound/!61) The results are shown in Table 9.

Test Example 9゜ Rice Sesame Leaf Blight Control Effect Test A hydrating powder as in Example 2 was diluted with water to a predetermined concentration on paddy rice seedlings (variety: Strain) at the 4-leaf stage grown in a 10C1rL clay pot. It was suspended and sprayed to thoroughly wet the leaves.

After drying the leaves, a spore suspension of rice sesame leaf blight was spray inoculated.
The temperature was maintained at 27-28°C and high humidity.

Four days after inoculation, the number of lesions was investigated for 1 plant/plant, 16 plants/pot, and 3 pots/treatment, and the suppression rate was calculated using the following formula.

The results are shown in Table 10. Suppression rate (%) = (l - total number of lesions in 1 area) x 100 total number of lesions in untreated area Test example 10゜Rice sheath blight control effect test 10 cm in diameter, paddy rice grown in a clay pot (variety: streaked) ) at the 5th leaf stage of the tree, an irrigation agent as in Example 2 was diluted and suspended in water to a predetermined concentration and sprayed so that the leaves and leaf sheaths ζ were sufficiently wetted.

After drying the leaf surface, the outermost periphery of the rice strangle blight bacterial flora, which had been cultured in advance on horsetail sugar medium, was punched out with a 5 mm diameter cork pole.The obtained mycelial disk was placed between the leaf sheaths and inoculated, and the outside was inoculated with distilled water. Cover the rice with absorbent cotton soaked in
Cover the area from 1/3 to 3/4 to maintain humidity, and leave it at around 30°C to develop the disease.

Eight days after inoculation, the lesion lengths of each inoculated stem were measured for 5 stems/pot and 3 pots/treated, and compared between the untreated and untreated stems.

The results are shown in Table 11G. Test Example 11゜Grape 1 Disease control effect test A hydrating powder as in Example 2 is diluted and suspended in water to a predetermined concentration on a potted grape seedling (variety: Koshu), and the front and back of the leaves are thoroughly wetted. I sprayed it like this and left it in a plastic greenhouse.

After 4 days, leaves are cut from the sprayed trees, spray inoculated with a spore suspension of the downy mildew fungus collected from the diseased leaves, and the disease is caused to develop under conditions of 18-23° C. and high humidity (trowel).

Ten days after inoculation, the degree of disease was investigated on 3 leaves/plot based on the 0th investigation standard, and expressed as the average degree of disease per leaf.

The results are shown in Table 12. Survey standard morbidity Degree of disease: 0 No disease: 0.5 Disease area rate: 10% or less 1
〃 10-25% 2 0 25-50% 3 〃 50-75% 4 〃 75% or more

Claims (1)

[Claims] 1 General formula (wherein R is H, 2-CI, 4-CI■314-NO
Represents 2. ) An agricultural and horticultural fungicide characterized by containing N-substituted penzoyl-N'-trichloroethylidenehydrazine as an active ingredient.