JPH0481961B2 - - Google Patents

Description

[Detailed description of the invention]

INDUSTRIAL APPLICATION FIELD The present invention relates to a method for preventing contamination of crops. More specifically, the present invention utilizes a formula widely used as an agricultural fungicide. The present invention relates to a method for preventing contamination of agricultural crops caused by the anhydrous salt of a copper chelate compound of 8-oxyquinoline. The above-mentioned copper chelate compound anhydrous salt of 8-oxyquinoline has strong bactericidal activity and broad bactericidal activity against a wide variety of pathogens, so it is used for agricultural purposes as well as
It is a useful compound that is widely used for industrial and pharmaceutical purposes. However, since this compound has a unique color tone (dark yellow-green), when used as a fungicide for agricultural and horticultural purposes, it has the disadvantage that contamination of agricultural products becomes noticeable, significantly impairing marketability. In particular, when spraying is repeated until just before harvest to protect crops from pathogens, the spray residue of the chemical solution can cause the fruit to have a poor color tone and rough skin, which can significantly reduce the commercial value, and for leafy vegetables, it can cause The color tone disappears, ocher spots remain, and the product quality is greatly reduced. Similarly, ornamental plants exhibit the appearance of green leaves covered with dirt, which seriously impairs their ornamental quality. The present invention relates to a method for preventing such contamination of crops. Prior Art As a method for preventing the contamination of agricultural crops caused by anhydrous salts of copper chelate compounds of 8-oxyquinoline, Japanese Patent Publication No. 36242/1987 discloses various types of dihydrate salts of copper chelate compounds of 8-oxyquinoline. It has been shown that it does not contaminate crops and has fungicidal activity equivalent to anhydrous salt. Furthermore, according to this patent publication, the dihydrate salt is 8
- It is said that the compound produced during the production of the copper chelate compound of oxyquinoline can be prepared by drying it at a low temperature, or by adding an auxiliary agent that can be used as an agricultural chemical without performing the drying process. However, since two molecules of expensive 8-oxyquinoline are used in the production of this dihydrate salt, the cost is high and its wide use is currently restricted. In addition, the bactericidal effect itself is the same as that of anhydrous salt, and it does not necessarily show excellent effects against all types of bacteria. There was a strong desire for a method to prevent contamination of crops that would utilize this. Problems to be Solved by the Invention It is possible to prevent the contamination of crops caused by the anhydrous salt of a copper chelate compound of 8-oxyquinoline, and to use an agent that has a bactericidal effect superior to that of the copper chelate compound. It is an object of the present invention to establish a method for preventing contamination of crops. Means for Solving the Problems The present inventors have conducted various studies on copper chelate compound derivatives of 8-oxyquinoline that can prevent contamination of crops without impairing the bactericidal activity of the anhydrous salt of the copper chelate compound of 8-oxyquinoline. As a result, 8-
Oxyquinoline and general formula (In the formula, X represents O or S, Y is H, Cl,
Represents Br, I or NO ₂ , R is H or -
A general formula obtained by reacting salicylic acid or thiosalicylic acid represented by (representing COCH ₃ ) or their substituted products with inorganic copper salts under alkaline conditions in an aqueous solvent system. The composite copper chelate compound (hereinafter referred to as the present compound) represented by the formula (wherein X, Y, and R are as described above) exhibits a bactericidal effect equivalent to or higher than that of the anhydrous salt of a copper chelate compound of 8-oxyquinoline. This research was completed after discovering that this is an extremely useful fungicide that has a high bactericidal effect against bacterial diseases and does not cause any contamination of crops. The present compound used in the method of the present invention can be synthesized, for example, by the following method. Dissolve 3 g of caustic soda in 300 ml of warm water, add 14.5 g of 8-okiiquinoline, and heat and stir to dissolve. Next, 13.8 g of salicylic acid was added, the reaction solution was heated to 80°C and stirred, and a warm aqueous solution of 25.0 g (0.1 mol) of copper sulfate/5H ₂ O was added thereto.
Add 100ml. At the beginning of the reaction, yellow-green crystals precipitate, but soon green crystals begin to precipitate. 80
Stir for 1 hour at ℃, and after cooling, filter off the crystals. The crystals are washed twice with water and dried at 70°C for about 5 hours to obtain 34.2 g of green crystals. Yield 98.7%. Using various substituted products of 8-oxyquinoline and salicylic acid represented by the above general formula, the corresponding compounds of the present invention can be obtained in high yields in the same manner as described above. Table 1 shows the main physical properties of the compound thus obtained.

[Table] In actual use, these compounds are prepared by mixing the active ingredients with one or more conventional agricultural chemical additives or auxiliaries according to the usual agricultural chemical formulation method.
It can be used in any dosage form such as wettable powders, granules, powders, liquids, and pastes. For example, these present compounds may be supported on solid carriers such as clay, talc, white carbon, diatomaceous earth, bentonite, etc., and ionic or Wettable powders or powders can be obtained by mixing and grinding with nonionic emulsifiers or dispersants, and if necessary, wetting agents, protective colloids, etc. The crop contamination preventive agent containing the present compound having a fungicidal effect used in the method of the present invention can also be used in combination with other fungicides, insecticides, local growth regulators, fertilizers, etc. This compound has been found to have extremely wide applicability in its fungicidal effect. For example, apple leaf spot disease, leaf spot disease, pear leaf spot disease, black leaf spot disease, persimmon anthracnose, powdery mildew, leaf fall disease, grape leaf spot disease, downy mildew, gray mold, and peach leaf curl. diseases, scab of citrus, black spot, canker, soft rot of Chinese cabbage, black rot of cabbage, yellow cucumber, bacterial spot of melon, downy mildew, anthracnose, late blight, watermelon, pumpkin Downy mildew, anthracnose, late blight of chiya and makuwa, bacterial spot disease of lettuce, soft rot, turf, snow rot of wheat, late blight of green pepper,
It is mentioned that it has excellent bacterial effects against late blight of onions, bacterial wilt of carnation, etc. Moreover, the crops to which this compound is applied retain their fresh green color and do not exhibit any contamination that occurs when anhydrous salts of copper chelate compounds of 8-oxyquinoline are applied. Therefore, the fungicide containing this compound can be used as a fungicide for spraying on the foliage of fruit vegetables such as cucumbers, eggplants, watermelons, and pumpkins, or on Chinese cabbage, Chinese cabbage, etc.
It can be used as a fungicide for spraying on leaves of leafy vegetables such as cabbage, lettuce, and spinach, or as a fungicide for spraying on fruit trees such as apples, pears, grapes, peaches, citrus fruits, and persimmons, or for plants that require aesthetics, such as lawns. It can be safely applied as a fungicide for spraying on the leaves of ornamental plants without worrying about crop contamination. Furthermore, this compound is stable under normal temperatures, sunlight, and atmospheric pressure, and can maintain its physical and chemical properties when used as a fungicide for agriculture and horticulture. Next, we will give examples of formulations. Formulation example Weight% Cu(OX)(SA) ^* Sodium lignin sulfonate 5 Polyoxyethylene alkyl phenol ether
1 Clay 44 100 *(OX): 8-oxyquinoline (SA): Salicylic acid The above components are mixed and ground in the above weight ratio and formulated into a wettable powder. When spraying, mix and dilute with a certain amount of water and spray a sufficient amount over the entire crop. Next, we will explain a test example in which this compound was compared with the anhydrous salt of a copper chelate compound of 8-oxyquinoline as an agricultural and horticultural fungicide, and showed equivalent potency in terms of bactericidal activity and no contaminating properties. do. Test Example 1 Apple Spot Leaf Disease Control Test A sufficient amount of a chemical solution of a predetermined concentration of a wettable powder prepared as described in the formulation example was sprayed on new apple cuttings placed in water in an Erlenmeyer flask, and air-dried. One day later, a spore suspension of Alternaria mali was spray inoculated. This was left in a humid room at a temperature of 26 to 28°C for 24 hours, then transferred to a greenhouse, and two days after inoculation, the number of diseased leaves was investigated for the five upper leaves according to the degree of disease onset as shown below, and the control value was calculated using the formula below. . Disease severity Spot area rate 5 50-100% 4 25-50% 3 10-25% 2 5-10% 1 1-5% 0 0 Disease severity = Σ (lung disease severity x number of leaves) / number of investigated leaves x 5 Control value = 1 - disease severity in treated area / disease severity in untreated area x 10
0 The degree of contamination was evaluated using the following criteria. - No contamination (no drug adhesion visible to the naked eye) + Minor contamination (medicine adhesion visible to the naked eye) ++ Large contamination (significant drug adhesion visible to the naked eye)

[Table] Expresses the same meaning as the number.
Test Example 2 Citrus black spot control test A sufficient amount of a predetermined concentration of a hydrating powder prepared as described in the formulation example was sprayed on potted summer citrus seedlings with new leaves, and after air drying, A day later, a spore suspension of Diaporthe citri was inoculated by spraying. This was left in a humid room at a temperature of 24 to 25°C for 24 hours and then transferred to a greenhouse. Twenty days after inoculation, the number of diseased leaves was investigated for all new leaves in four pots in each group according to the severity of disease as shown below, and the severity of disease was calculated using the following formula. Disease severity Disease severity 3 Severe disease 2 Moderate disease 1 Slight disease 0 No disease disease severity = Σ (Stage of disease x number of leaves) / Number of leaves examined x 3 The criteria for contamination level are as in Test Example 1. It is the same as shown.

[Table] Expresses the same meaning as the number.
The copper chelate compound dihydrate of 8-oxyquinoline uses two molecules of expensive 8-oxyquinoline in its production, but in this compound, one molecule is made from the cheaper salicylic acid. , 8
-It has the advantage that it can be produced much more cheaply than the copper chelate compound dihydrate of oxyquinoline. Furthermore, this compound has a more bactericidal effect on bacterial diseases such as citrus canker disease (Xanthomonas citri) and canker blight (Pseudomonas lachrymans) compared to the copper chelate compound dihydrate of 8-oxyquinoline. It has been recognized that the present invention is highly effective, making it a more preferred crop contamination preventive agent, and provides an extremely useful improver as an agricultural and horticultural fungicide. The following test example shows that the present compound exhibits higher bactericidal activity against bacterial pathogens than the copper chelate compound dihydrate of 8-oxyquinoline. Test Example 3 Bactericidal activity test against crop parasitic bacteria A hydrating agent of this compound was added to a PDA medium or a peptone agar medium to a specified concentration, and a 9 cm diameter
It was poured into a sieve and solidified. Then, inoculate the test bacteria pre-cultured in advance into the above-mentioned shear dish and heat at 25℃.
After culturing for a predetermined number of days, the growth level of the bacteria was investigated using the following criteria. −: No growth +: Growth suppression ++: Good growth

【table】

[Table] Effects of the Invention By using the present compound, pathogens of crops can be effectively sterilized without contaminating the crops as caused by the anhydrous salt of a copper chelate compound of 8-oxyquinoline. In addition, this compound exhibits higher activity against bacterial diseases than 8-oxyquinoline copper chelate compound dihydrate, which is used for the same purpose, so we expect that the use of this compound will provide a wider range of bactericidal effects. be able to.

Claims (1)

[Claims] 1. General formula (In the formula, X represents O or S, Y is H, Cl,
Represents Br, I or NO ₂ , R is H or -
A method for preventing contamination of crops, which is characterized by using an agricultural and horticultural fungicide containing a complex copper chelate compound represented by COCH ₃ as an active ingredient. 2. The method according to claim 1, which uses an agricultural and horticultural fungicide containing a composite copper chelate compound of 8-oxyquinoline and salicylic acid as an active ingredient. 3. The method according to claim 1, which uses an agricultural and horticultural fungicide containing a composite copper chelate compound of 8-oxyquinoline and 5-chlorsalicylic acid as an active ingredient. 4 Claim 1 which uses an agricultural and horticultural fungicide containing a complex copper chelate compound of 8-oxyquinoline and 3,5-dibromsalicylic acid as an active ingredient
The method described in section. 5 Claim 1, which uses an agricultural and horticultural fungicide containing a complex copper chelate compound of 8-oxyquinoline and 3,5-diiodosalicylic acid as an active ingredient
The method described in section. 6 Claim 1 which uses an agricultural and horticultural fungicide containing a complex copper chelate compound of 8-oxyquinoline and 3,5-dinitrosalicylic acid as an active ingredient
The method described in section. 7. The method according to claim 1, which uses an agricultural and horticultural fungicide containing a composite copper chelate compound of 8-oxyquinoline and thiosalicylic acid as an active ingredient. 8. The method according to claim 1, which uses an agricultural and horticultural fungicide containing a composite copper chelate compound of 8-oxyquinoline and acetylsalicylic acid as an active ingredient.