JPS63402B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to an acaricide, and more particularly to an acaricide containing antibiotic B-41D and a diethyl phosphate, diethyl phosphorothioate, diethyl phosphorodithioate, or ethyl phosphonothioate organophosphorus insecticide as active ingredients. Regarding. Spider mites are the most harmful plant parasitic mites to plants, and there are almost no crops, including fruit crops, that are not damaged by spider mites, and the damage caused is enormous. Additionally, spider mites are resistant to the organophosphorus insecticides currently in use, and their control has become a major problem. A group of macrolide antibiotics isolated from the B-41-146 strain of the genus Streptomyces is designated as B-41 in JP-A-50-29742, and
9 of A ₁ , A ₂ , A ₃ , A ₄ , B ₁ , B ₂ , B ₃ , C ₁ and C ₂
Species mentioned. Four more compounds were isolated and the structures of all 13 compounds determined and published in The Journal of Antibiotics.
Antibiotios) 29(3), pages 76-14 to 76-16 and the same magazine.
29(6), pp. 76-35 to 76-42. and,
These B-41 antibiotics were named milbemycins. These B-41 compounds are known to have insecticidal and acaricidal activity from the above-mentioned literature. Furthermore, B-, which newly belongs to the genus Streptomyces,
From the culture of strain 41-146, the following formula () A new antibiotic B-41D was discovered with
B41D is the above-mentioned B-41 compound, especially the structurally similar B-
It was known to have much stronger acaricidal activity compared to 41A ₃ and B-41A ₄ . The present invention provides an acaricide containing this new antibiotic B-41D and a diethyl phosphate, diethyl phosphorothioate, diethyl phosphorodithioate, or ethyl phosphonothioate type organophosphorus insecticide as active ingredients. Mixtures of B-41D with organophosphorus insecticides containing the mono- or diethyl ester structure described above exhibit a specific synergistic effect and are superior to those of organophosphorus insecticides containing dimethyl or dipropyl ester structures such as Marathon, Fenitrothion, Propaphos. Mixtures do not show this effect. This indicates that there is a relationship between the decomposition metabolism of B-41D in the bodies of spider mites and the structure of organic phosphorus agents, and that organophosphorus agents containing mono- or diethyl ester structures are responsible for the mechanism of B-41D's resistance to spider mites. It is presumed that this is due to the fact that it is suppressed. As described above, the acaricide of the present invention can control spider mites that are resistant not only to organophosphorus insecticides but also to B-41, and is more effective than when each of these compounds is used alone. This shows an unexpected synergistic effect in that the effect is significantly greater when the mixture is applied. The mycological properties of Streptomyces strain B-41-146, which produces antibiotic B-41D, are described in detail in JP-A-50-29742. It has been deposited at the Microbial Technology Research Institute, and its microproduct accession number is Microbiological Research Institute No. 1438. B-41D can be obtained by culturing the B-41-146 strain in an appropriate medium and harvesting it. As the nutrient source, any known nutrient source conventionally used for culturing Streptomyces bacteria can be used.
For example, glucose, sucrose, starch, glycerin, starch syrup, molasses, soybean oil, etc. can be used as carbon sources. Nitrogen sources include soy flour, wheat germ, meat extract, peptone, yeast strains, corn steep liquor, ammonium sulfate,
Sodium nitrate etc. can be used. In addition, inorganic salts such as calcium carbonate, common salt, potassium chloride, and phosphates are added as necessary, and organic and inorganic substances that support the growth of bacteria and promote the production of B-41D are added as appropriate. be able to. The most suitable culture method is the liquid culture method, especially the deep culture method, similar to the method for producing general antibiotics. Cultivation is carried out under aerobic conditions, and the appropriate temperature for cultivation is 22-30℃, but in many cases
Culture at around 28℃. Production of B-41D reaches its maximum value in 5 to 10 days in both shaking culture and tank culture. When collecting B-41D from cultures, adsorbents such as activated carbon, alumina, and silica gel, synthetic adsorbents such as Diaion HP-20 (manufactured by Mitsubishi Kasei Corporation), Avicel (manufactured by Asahi Kasei Corporation), paper, etc. Fixatives, ion exchange resins, ion exchange gels, etc. can be used, but the collection method shown below is the most effective. The target product is dissolved in methanol water by separating the culture using a supernatant such as diatomaceous earth and extracting the resulting cake with methanol. After adding water to this, extraction is performed with n-hexane, and this is concentrated under reduced pressure to obtain an oily substance containing the target product. This was adsorbed on a column of silica gel (Wako Gel C-200), eluted with n-hexane:acetone (95:5), fractions containing the target product were collected, concentrated under reduced pressure, and made into an oil again. Add a small amount of methanol to this and use Sephadex LH-20.
(manufactured by Pharmacia) column, developed with methanol, collected fractions containing the target product, concentrated under reduced pressure, dissolved the residue obtained here in a small amount of methanol, added water and left at room temperature. Then, B-41D is obtained in crystalline form. B-41D has the following physical and chemical properties. (1) Appearance: Amorphous powder (2) Elemental analysis values (%): C: 71.40, H: 8.82, O: 20.22 (3) Chemical structural formula As shown in formula () above. (4) Molecular weight: 556 (5) Ultraviolet absorption spectrum: Shown in Figure 1. Maximum absorption: 237 mμ (shoulder, ε = 29400), 243 mμ (ε = 30500) (6) Infrared absorption spectrum: The spectrum measured in the KBr tablet is shown in Figure 2. (7) NMR spectrum: Nuclear magnetic resonance absorption spectrum (100M
Hz) as shown in Figure 3. (8) Solubility: Easily soluble in n-hexane, ethyl acetate, acetone, ethanol, and methanol, slightly soluble in water. (9) Thin layer chromatography: Rf value 0.40 Adsorbent: Merck Kieslgel 60 F ₂₅₄ Developer solvent: Dioxane: Carbon tetrachloride (18:82) B-41D can be used after isolation and purification, but its Alternatively, the purification can be stopped at any stage and the crude product can be used as the active ingredient. When using a mixture containing two or more B-41 compounds without completely separating the various B-41 compounds obtained from purification of the culture, 100% acaricidal at a concentration of 5 ppm is recommended. It is sufficient to purify it to the extent that a certain percentage can be obtained.
Preferably, the B-41D content in the crude portion is about 50%, with the remainder comprising contaminants from the broth. The diethyl phosphate, diethyl phosphorothioate, diethyl phosphorodithioate and ethyl phosphonothioate type organophosphorus insecticides used in the present invention can be exemplified below. (1) 0.0-diethyl 0-(5-phenyl-3
-isoxazolyl) phosphorothioate (isoxathion), (2) 0-ethyl 0-p-nitrophenyl phenyl phosphonothioate (EPN), (3) 0,0-ethyl 0-p-nitrophenyl phosphorothioate (parathion), (4) 0,0-diethyl 0-(2-isopropyl-4-methyl-6-pyrimidinyl) phosphorothioate (Diazinon), (5) 0-ethyl 0-(4-cyanophenyl)benzenephosphonothioate (CYP), (6) 0・0-diethyl S-(2,5-dichlorophenylthiomethyl)phosphorodithioate (fenkapton), (7) 0-diethyl 0-[2-chloro-1-
(2,4-dichlorophenyl)vinyl]phosphate (CVP), (8) 0,0-diethyl S-(N-ethoxycarbonyl, N-methyl carbamoylmethyl)phosphorodithioate (mecarbam), (9) 0・0・0′・0′-Tetraethyl S・S′-methylene bisphosphorodithioate (ethion), (10) 0・0-diethyl S-(6-chloro-2-
Oxobenzoxazolin-3-yl) methyl diethyl phosphorodithioate (phosalone) and (11)S-(2-chloro-1-phthalimidoethyl) 0,0-diethyl phosphorodithioate (diaryphor) Synergistic effect in the present invention appears particularly strongly at a specific mixing ratio of both compounds. However, the mixing ratio can be varied over a relatively wide range. Generally speaking, the organic phosphorus agent is preferably used in an amount of 1 to 5 parts by weight per 1 part by weight of B-41D;
More preferably, it is 1 to 3 parts by weight. When the composition of the present invention is actually used in the field, the active ingredient is dissolved or dispersed in a liquid carrier, or mixed with a solid carrier, and auxiliary agents such as emulsifiers, spreading agents, and penetrating agents are added to this. Emulsion,
It can be used in the form of powders, wettable powders, powders, etc. Liquid carriers include alcohols such as methanol and ethanol; ketones such as acetone and methyl ethyl ketone; ethers such as dioxane and cellosolve; aliphatic hydrocarbons such as kerosene and kerosene; aromatic hydrocarbons such as benzene and toluene; Halogenated hydrocarbons such as chloroform and carbon tetrachloride;
Acid amides such as dimethylformamide; esters such as ethyl acetate are suitable;
A species or two or more species may be used. Suitable solid carriers include vegetable powder, kaolin, bentonite, acid clay, talc, diatomaceous earth, alumina, activated carbon, etc., and one or more of these may be used. Auxiliary agents include various types of surfactants. For example, nonionic surfactants (polyoxyethylene alkylaryl ether, polyoxyethylene sorbitan monolaurate, etc.),
Cationic surfactants (alkyldimethylbenzylammonium chloride, alkylpyridinium chloride, etc.), anionic surfactants (alkylbenzenesulfonates, ligninsulfonates, higher alcohol sulfates), amphoteric surfactants (alkyldimethylbetaine, dodecylaminoethylglycine, etc.). These adjuvants may be used alone or as a mixture of two or more. Before use, the emulsion or hydrating agent may be further diluted with water to a predetermined concentration. It is also possible to mix and use other active ingredients such as herbicides, insecticides, and fungicides that do not impair the activity of the composition of the present invention. In particular, even greater effects can be expected by incorporating machine oil. Next, the composition of the present invention will be specifically explained by giving formulation examples and test examples. All parts in the text indicate parts by weight. Combination example 1 3 parts of B-41D, 20 parts of EPN, paracol
EOMX (Paracol is a trademark name of Nippon Nyukazai Co., Ltd.) 10
400 parts of emulsion obtained by mixing 67 parts of xylene and 67 parts of
Use by diluting it twice. Formulation Example 2 An emulsion prepared by mixing 10 parts of B-41D, 50 parts of isoxathion, 15 parts of Paracol SL and 20 parts of xylene is diluted 1000 to 2000 times and used. Formulation example 3 2 parts of B-41D, 6 parts of isoxathion, 60 parts of machine oil, 7 parts of Minemaru-360-SP, NE-560-
An emulsion obtained by mixing 3 parts of SFC and 20 parts of xylene is diluted 400 times and used. Test Example 1 Organic Phosphate B-41 Resistant Two-spotted Spider Mite Immersion Test Approximately 30 female adult two-spotted spider mites were inoculated onto a piece of cowpea leaf (approximately 20 cm ² ) on paper moistened with water. Next, the B-41D emulsion was diluted with the organic phosphorus solution shown in Table 1, and the active ingredient content of the phosphorus + B-41D mixture was adjusted to 100 ppm + 30 ppm, 100 ppm + 10 ppm, and 100 ppm + 10 ppm, respectively.
Adjust the concentration to 100 ppm + 3 ppm, set the cowpea leaf pieces in a Mizuho rotary spray tower, spray 5 ml, and maintain the paper in a constant temperature room at 25°C for 3 days to prevent the paper from drying out to determine the dead mite rate (%). investigated. The results are shown in Table 1.

【table】

[Table] Tylthiophenyl phosphate From Table 1, it is diethyl phosphate.
CVP; isoxathion, parathion, and diazinon, which are diethyl phosphorothioates; fencaptone, mecarbam, ethion, phosalone, and diaryfol, which are diethyl phosphorodithioates; EPN, which is ethyl phosphonothioate;
It can be seen that methyl parathion and fenitrothion, which are dimethyl phosphorothioates; marathon, which is dimethyl phosphorodithioate; and propafos, which is dipropyl phosphate, do not show a synergistic effect when mixed with milbemycin. Test Example 2 Pot test against organic phosphorus agent-B-41 resistant two-spotted spider mite Organic phosphorus agent, B-
30 adult female 41-resistant two-spotted spider mites are inoculated and allowed to spawn for 4 days. Next, a diluted solution of the emulsion with the formulation shown in Formulation Example 1 was sprayed with a small sprayer to the extent that the front and back of the leaves were sufficiently wet and dripped, and after being left at a temperature of 25 to 30°C for two weeks, the number of living spider mites (adults and total number of larvae) were counted. The results are shown in Table 2.

[Table] Test Example 3 Orange Spider Mite Pot Test Orange spider mites resistant to organic phosphorus agents and B-41 are inoculated into 4-year-old orange pots, and when 2 to 3 female adult orange spider mites are infesting each leaf, the above formulation is applied. When a 400-fold diluted solution of the emulsion in Example 3 was sprayed evenly over the front and back of leaves to the extent that it dripped, 4
No occurrence of citrus spider mites was observed during the week.

[Brief explanation of the drawing]

Figure 1 shows the ultraviolet absorption spectrum of B-41D, Figure 2 shows the infrared absorption spectrum of the same substance, and Figure 3 shows the infrared absorption spectrum of the same substance.
The figure shows the nuclear magnetic resonance absorption spectrum of the same material.

Claims (1)

[Scope of Claims] 1. A miticide containing antibiotic B-41D and a diethyl phosphate, diethyl phosphorothioate, diethyl phosphorodithioate, or ethyl phosphonothioate-based organophosphorus insecticide as active ingredients. 2 The organophosphorus insecticide is 0,0-diethyl 0-(5-phenyl-3-
isoxazolyl) phosphorothioate, 0-ethyl 0-p-nitrophenyl phenyl phosphonothioate, 0,0-diethyl 0-p-nitrophenyl phosphorothioate, 0,0-diethyl 0-(2-isopropyl-
4-Methyl-6-pyrimidinyl) phosphorothioate, 0-ethyl 0-(4-cyanophenyl)benzene phosphonothioate, 0.0-diethyl S-(2.5-dichlorophenylthiomethyl) phosphorodithioate, 0. 0-diethyl 0-[2-chloro-1-
(2,4-dichlorophenyl)vinyl]phosphate, 0,0-diethyl S-(N-ethoxycarbonyl, N-methyl carbamoylmethyl)phosphorodithioate, 0,0,0',0'-tetraethyl S. S'-methylene bisphosphorodithioate, 0,0-diethyl S-(6-chloro-2-oxobenzoxazolin-3-yl)methyl diethyl phosphorodithioate and S-(2-chloro-1-phthalimidoethyl )
The acaricide according to claim 1, which is one or more selected from the group consisting of 0.0-diethylphosphorodithioate.