CS262664B2 - Fungicide for protection of plants - Google Patents

Description

The invention relates to a novel, improved fungicidal plant protection product.

Several articles and patents have been published in recent years concerning the use of cyclodextrin in plant protection products [Newnyvedel, 19, p. 364 (1983); J. Szejtli: Cyclodextrins and their Inclusion Complexes, Kiadó Academy, Budapest, 19 & 2]. By forming complex compounds of molinate (S-ethyl-N, N-hexamethylenediocarbamate), bentiocarib (S-4-chlorobenzyldiethylthiocarbamate) and dichlorphos (2,2-dichlorvinyldimethylphosphate) the volatility of the active ingredient is greatly reduced and the pesticide's effectiveness lasts for longer idobas [Kikasa Chemical Industrial What.; KOKAI No. 80.81806; German Patent Publication No. 2,442,316 (1974); Acta Chem. Acad. Sci. Hung., 107, 195 (1981)]. Methylparathion (O, O-dimethyl-O-4-nitrophenylphosphorothioate) and natural pyrethrins and pyrethroids are converted to complex compounds with cyclodextrin, thereby greatly enhancing their light and oxygen stability [Fist. Sci., 11, p. 134 (1980J; U.S. Patent 3,846,551 (1974); Nippon Noyaku Gakkaishi 1, p. 41 (1976); 2, p. 41 (1977)) .Dichlobenyl (2,6-dichlorobenzonitrile). , which is an active ingredient of some formulations, easily sublimates and sticks to its granules, which can be prevented by forming its complex compound with cyclodextrin [5 th Int. Cong. Pesticide Chem. (IUPAC) Kyoto (1983.) ].

By forming a complex compound of 2-chloromethanephosphonic acid with a cyclodextrin, the release of ethylene upon contact of the complex compound with plant tissue takes place over a long period of time, which is more efficient than the supply of ethylene to the fast-acting active ingredient [Acta Chim. Acad. Sci. Hung., 107, 231 (1981)].

Based on current knowledge, it was not possible to predict that cycloidextrin would synergize the efficacy of fungicides.

It is an object of the invention to provide cyclodextrin-containing fungicidal compositions in which cyclodextrin synergistically synergizes the efficacy of known fungicidally active ingredients. This results in a higher dose of the same fungicidally active ingredient or the same fungicidal effect can be achieved by using a lower dose of the active ingredient, which is a very important advantage in terms of both savings and environmental hazards.

Accordingly, the present invention provides a fungicidal plant protection product comprising 2-methoxycarbonylaminoibenzimidazole or 1-butylcarbamoylbenzimidazole-2-methylcarbamate or 1- (3,5-dichlorophenyl) -3-methoxymethylpyrroliidine-2,5 as a fungicidally active ingredient. -dione or 2,4'-dichloro- (pyrimidin-5-yl) - diphenylmethanol in an amount of 3 to 90% by weight in admixture with a cyclodextrin in an amount of 1 to 90 ® / o, the weight ratio of the fungicidally active ingredient to cyclodextrin being 49: 1 to 1: 5, preferably (2 to 5): 1, and optionally conventional auxiliaries.

Cyclodextrin which can be used is [alpha], [beta] - or [beta] -cyclodextrin.

The aforementioned fungicidally active ingredients of the composition of the invention are commonly referred to as trivial names, i.e. 1-butylcarbamoylbenzimido-benomyl zol-2-methylcarbamate 2-methoxycarbonylamino-BCM benzimidazole

1- (3,5-Dichloro-phenyl) -3-meth-methomeclan xymethyl-pyrrolidine-2,5-dione 2,4‘-dichloro-α- (pyrimidin-5- = phenarimol-yl) -diphenylmethanol

In a preferred embodiment of the invention, the ratio of the amount of said active ingredients to the amount of cyclodextrin is as follows:

benomyl: cyclodextrin = (2 to 5): 1 BCM: cyclodextrin = (2 to 5): 1 metomeclane: cyclodextrin - (2 to 20): 1 phenarimol: cyclodextrin = (1 to 100): 10

The fungicidal treatment with the composition according to the invention consists in applying to the plants or other surface to be treated a composition according to the invention, preferably in an amount of 0.5 to 6 kg per hectare, in particular 1.2 to 1.6 kg per 1 hectare. hectare.

The invention is based on the discovery that known fungicidally active ingredients and cyclodextrin exhibit a synergistic effect resulting from one or both of the following:

- the intrinsic fungistatic activity of cyclodextrins, - the effect of cyclodextrins in increasing solubility.

The fungistatic activity of cyclodextrins has not been described hitherto. This efficacy can be demonstrated by the following test:

Agar broth containing 0.1 - 0.2 0.5 - - 1.0 - 2.0 - 5.0 - 10.0 - 20.0 - 100.0 - - 200.0 - is prepared in Petri dishes. 400.0 - 800.0 - 1200.0 - 1,500.0 - 2,000.0 - 3,000.0 µg of β-cyclodextrin in 1 ml. Mycelium discs were stabbed from the cultures of the three fungi tested and plated onto agar broth in Petri dishes. These plates are then incubated in a thermostat, whereupon colony diameter is increased and compared to control. The morphology of the colonies and the diffusion of the dyes produced by the fungi into the culture medium are also observed. The results are shown in Table 1.

Table 1

The fungistatic effect of β-cyclodextrin

Concentration Inhibition (%) microorganism

Rhizoctonia Sclerotinia - Alternaria solani sclerotiorum tenuis

000 19 16 15

1400 17 14 12

400 6 11 10

199 3 12 7

At a dose of 0.1 to 20 μ§. ml ¹ is a qualitative effect of β-cyclodextrin. The fungistatic effect of cyclodextrin is manifested by a change in the morphology, structure and color of the colonies and a change in the amount of dye penetrated into the culture medium. However, at higher doses, the effect of cyclodextrin is already quantitative, so that the colony diameter reduction is already measurable and the amount of biomass produced is reduced to a value that can be evaluated (Table 1j). .

The main feature of the effect of cyclodextrin on enhancing solubility due to the formation of inclusion complex compounds is that in an aqueous solution, in addition to the molecularly dispersed (i.e., actually dissolved) active ingredient and mycelium ¹ consisting of several molecules or their clusters (microcrystalline) an inclusion complex compound of cyclodextrin with the active ingredient is similarly dispersed.

Since the system is characterized by an unusually dynamic equilibrium (within 10 ^-8 s ^-1 ), the active ingredient incorporated into the inclusion complex compound has the same effect in terms of absorption as the free dissolved active ingredient.

Thus, the concentration of molecularly dispersed molecules that are suitable for direct absorption can be significantly increased by cyclodextrins, which increases the rate of absorption, i.e. the same effect can be achieved by using a smaller dose of the active ingredient.

The beneficial effect of cyclodextrin on the solubility of the active ingredients is exemplified by the toenomyl example. This active ingredient (1-butylcarbamoylbenzimidazole-2-methylcarhamate) is a systemic fungicide that is poorly soluble in water, and dissolved in water rapidly decomposes to methylhenzimidazolecarbamate, which also has fungicidal effects but is even less soluble in water.

Shaking, first benomyl and also mixtures of benomyl cyclodextrin in water at 25 ^Q C was obtained by the solubility data shown in Table 2 (Benomyl, resp. A combination of benomyl with | 3-cyclodextrin was shaken in water at 25 ° C, whereupon the sample and the dissolved benomyl content of the filtrate is determined spectrophotometrically in ultraviolet light.)

Table 2

Increased solubility of benomyl by (3-cyclodextrin)

Duration of the experiment (minutes) amount of dissolved benomyl weighed: 1000 / zg. ml ¹ weighed:

170 μζ. ml ¹ benomyl +830 μ§. ml ¹ (3-cyclodextrin iUg.ml ¹ <% ^ g.ml ¹ '%

10 2 0.2 7 4.1 20 May 3 0.3 9 5.3 40 4,5 0.45 10 5.9 80 5 0.5 12 7.0 120 5 0.5 13 7.6

Table 2 - continued

Duration of the experiment (minutes) amount of dissolved benomyl weighed:

000, ug. ml ^-1 , µg. ml

-i weighed:

850 / tg. ml ^-1 +4 benomyl 150 .mu.g. ml ^-1 / 3-cyclodextrin μ% .ml ^-1 ® / o

10 3.5 0.07 12 1.4 20 May 4 0.08 16 1.9 40 6 0.12 17 2,0 80 8 0.16 18 2.1 120 9.5 0.19 19 Dec 2.2

Benomyl is marketed under the trade name Fundazol 50 WP; the active ingredient content in benomyl is 50%. Table 3 shows the solubility data of benomyl, a mixture of benomyl with cyclodextrin, Fundazole 50 WP and a mixture of Fundazol 50 WP with cyclodextrin. In each experiment were weighed 3000 jug.ml ^'1 test compounds are shaken at 25 ° C. Benomyl is 100% active ingredient; the benomyl content of the mixture of benomyl with cyclodextrin is 17.3%; the benomyl content of Fundazole 50 WP with cyclodextrin is 8.65%. From the results in Table 3, it is apparent that due to the formulation, the solubility of benomyl is increased four-fold.

Cyclodextrin alone causes a further 1.5 to 2-fold increase in solubility of both the original benomyl and the formulated Fundazole 50 WP. Taking into account that in the cyclodextrin-containing compositions the amount of benomyl active ingredient is considerably lower and at the same time that in aqueous solution the concentration of benomyl, which is responsible for the intrinsic biological effect, has risen, it has become clear that this must also occur in biological effect.

Table 3

Increased solubility of benomyl from Fundazole due to (3-cyclodextrin)

Duration of the Experiment Amount of Dissolved Benomyl (/ fg ml ^-1 ) (minutes) Benomyl Fundazol mixture, Benomyl Fundazole mixture with β-cyclodex- / β-cyclotrin dextrin

2

5

6

7

120 8

160 9

5 27 Mar: 40 8 28 42 11 29 44 13 30 46 13 31 48 13 32 49

The solubility of benomyl from various benomyl-containing formulations was determined by shaking with water at 25 ° C. 2 000 μ§ was weighed. ml ¹ solid, corresponding to the following amounts of benomyl:

in the case of benomyl alone: in the case of a mixture of benomyl with β-cyclodextrin: in the case of Fundazole 50 WP: in the case of a mixture of Fundazol 50 WP with β-cyclodextrin:

000 μξ. ^ml-1350 μξ. ml ¹ +1 650 μξ. ml ' ¹

.Ml 1000 micrograms ¹¹⁷⁵ micrograms. ml ¹

- | -.1 650 μξ. ml ¹

262864

The tests described below demonstrate surprising synergism between known fungicides and β-cyclodextrin. Stable, highly dispersed aqueous suspensions of the test materials are added to the agar broth at the desired concentration (0.1 to 200 µg. Ml ^-1 ), and the broth is then poured into petri dishes. Mycelium targets are punched from the surface of the test fungus cultures and transferred to petri dishes containing test materials. Incubation is carried out in a thermostat, whereupon colony diameter is measured and compared to the control diameter. The tests are performed in triplicate.

In Table 4, the effect is maintained Fundazol 50 WP fungicide (benomyl content of a ^50%) and a mixture of '50 Fundazol WP 10 ° / o / 3-cyclodextrin. The results clearly demonstrate the synergistic effect of β-cyclodextrin; higher efficacy is particularly significant when used against Botrytis cinerea and Monilia fructigena.

increase in efficiency (multiple)

Table 4

The fungicidal activity of Fundazol and recrystallized (3-cyclodextrin)

Microorganism ED 50 (g g of active ingredient in 1 ml)

Fundazole Fundazole-10 ° / ((3-cyclodextrin

Rhizoctonia solani 0.87 0.64 1.3 Sclerotinia sclerotiorum 0.12 0.05 2.4 Fusarium moniliforme 0.88 0.38 2.3 Botrytis cinerea 0.14 0.0125 10.2 Ascochyta pisi 0.72 0.25 2.9 Fusarium culmorum 0.77 0.44 1.7 Colletotrichum lini 0.68 0.5 1.3 Monilia fructigena 0.05 0.0125 4.0 Metomeclan is a contact fungicide by cyclodextrin. Table 5 is shown water-soluble [1- (3,5-dichlorophenyl) -3-methyl- fungicidal effect of metomeclan and a mixture of thoxymethylpyrrolidine-2,5-dione). tomeclan with 10% (3-cyclodextrin). The effect of metomeclan is significantly will increase Table 5 Increase the efficacy of metomeclan by adding 10% (3-cyclodextrin) tested microrganism ED 50 (µg active ingredient per ml) increase efficiency metomeclan metomeclan + 10% (multiple) 3-cyclodextrin Fusarium moniliforme 12 7 1.7 Alternaria tennis 2.9 1,8 1.6 Stemphylium radicinum 5.7 3.9 1.5 Rhizoctonia solani 3.3 2.3 1.4 Colletotrichum lini 25.5 8.9 2.9 Ascochyta pisi 4.6 2.8 1.6 Fusarium culmorum 16.5 7.5 2.2 Alternaria * crassa 3.9 2.2 1,8

In vivo tests * are performed on cereal mildew (host parasite) using a combination of fenarimol [2,4olu-dichloro-α- (pyrimidin-5-yl) -diphenylethanol] with β-cyclodextrin. The tests are performed in triplicate * in phytotron under the usual experimental conditions (temperature 20 degrees Celsius, air humidity 90%, light intensity 9,000 lux).

In 11 cm diameter culture dishes, an average of 160 plants 5-6 cm in height are treated with 8 ml of a stable aqueous suspension containing the test material. The results are summarized in Table 6. Inhibitory potency was determined using the Hinfner-Papp formula using a contamination index.

Table 6

In vivo tests using a combination of fenarimol with β-cyclodextrin on powdery mildew of a host parasitic

Fenarimol concentration inhibitory activity (%)

(/tg.ml ¹ ) fenarimol mixture of fenarimol with β-cyclodextrin (ratio 1: 5) 10 100.0 100.0 5 99.4 100.0 2.5 87.2 98.2 1,25 73.5 83.2 0.625 29.4 42.3

Enhancement of the efficacy of 2-methoxycarbonylamino is indicated by the test results reported in the following benzobenzimidazole (BCM) by the addition of β-cycling Table 7. dextrin in an amount of 0.5% by weight to Table 7.

Inhibitory activity of Kolfugo complexes with β-cyclodextrin on Rhizoctonia solani

Concentration (µg ml- ¹ )

Inhibitory efficiency (%)

K 21.5 FW * K — 21.5 FW + 0.5 wt.

(3-cyclodextrin)

5.0

4.5 4,0

3.5 3,0

2.5 2,0

100.0 100.0 100.0 100.0 76.9 87.2 70.5 85.9 59.0 75.6 57.7 64.1 55.8 62.8

* Kolfugo 21.5 FW contains 2-methoxycarbonylaminobenzimidazole (BCM) in the form of an aqueous suspension at a weight concentration of 21.5% (flrmy-Chinoin product)

In another series of experiments, it is tested whether the known linear dextrins, prepared by thermal, enzymatic or acid decomposition of starch, have a similar effect to cyclodextrins. The results of these tests clearly show that only cyclodextrins have the above-mentioned fungicidally synergistic activity.

As a result of the synergistic effect of cyclodextrins, the dose of known and generally used fungicidally active ingredients can be greatly reduced to achieve the same or improved fungicidal effect, which reduces the cost of the active ingredients and also reduces the risk of environmental pollution.

Further details of the invention will be apparent from the examples which follow, but do not limit the scope of protection desired.

Example 1

Spray containing benomyl as an active ingredient

Benomyl is commercially available as a wettable powder spray having an active ingredient content of 50% under the name Fundazol 50 WP. An article having the same efficacy but containing less active ingredient is prepared as follows.

kg of benomyl pre-ground in an air mill and 15 kg of crystalline β-cyclodextrin with a moisture content of 13%, also pre-ground in an air mill, are mixed in a homogenizer with 40 kg of precipitated calcium carbonate, 5 kg of waste sulfide powder and 5 kg of an anionic surfactant containing 50 proc. water (preferably with Genapol PGM, i.e. Na-alkyl ether sulfate, preheated to 50 ° C). The homogenized material is dried, milled to crush the bonded particles and then packaged.

Example 1 a d 2

The procedure is as in Example 1; the individual components are comminuted, mixed, homogenized, dried and re-comminuted. The composition of the resulting mixture is as follows:

benomyl (based on 100% active ingredient) 40 kg precipitated calcium carbonate 40 kg

Tensiofix BC2 (mixture of Ca-C12-alkylbenzenesulfonate with C9-12 alkylphenol-polyethylene glycol-polypropylene glycol ether) 2.5 kg

Totamine (tetrahybrhodamine) 5 kg β-cyclodextrin 12.5 kg

Example 3

Seed treatment product containing benomyl as active ingredient benomyl (1-butylcarhamoylbenzimidazole-2-methylcarbamate)

Diotilane (Na-di-octylsulfosuccinate)

Evidet 27 (alkyl-polyglycol ether-Na) tylose N 20 (Na-carboxymethylcellulose j Aerosil "300" (synthetic silicic acid)

Safranin P extra crude mixture of cycliodextrins, spray-dried (β-cyclodextrin content approximately 48% α- and γ-cyclodextrin content 2%; partially decomposed starch content approximately 50% / o) precipitated calcium carbonate

Example 4

Seed treatment product containing Abem (2-methoxycarbonylaminobenzimidazole) as an active ingredient

The active ingredient Abem was decomposed with heating

The procedure is as in Example 1. The composition of the composition is as follows:

kg kg 1 kg

0.5 kg kg kg 21.5 kg is released in hydrochloric acid, and the solution is neutralized with an emulsion consisting of a mixture of ammonium hydroxide, paraffin oil and β-cyclodextrin. The resulting suspension is stabilized in a known manner by the addition of surfactants. The seed treatment composition has the following composition:

Abem (2-methoxycaribonylaminobenzimidazole) paraffin oil / 3-cyclodextrin ethylene glycol ammonium chloride (formed by neutralizing the solution in hydrochloric acid) about

Various surfactants:

Emulsogen M (fatty alcohol polyglycol ether)

Atlox 4,868 B (polyoxyalkylene ester complex compound with urea)

Triton X 45 (octyl-phenoxy-polyethoxyethanol)

Tensiofix L 051 (anti-foaming agent - oil emulsion)

Tensiofix 821 (polysaccharide) water to replenish to

15 Dec % 19.8 o / o 5 o / o 5.6 O / o 10 O / o

0.24%

1,6 Ψο

1.9%

About 0.2 / _{0.2 0/0}

100%

Claims (6)

1. A fungicidal plant protection product, characterized in that it contains 2-methoxycarbonylaminobenzimidazole or 1-1-butylcarbamoylbenzimidazole-2-methylcarbamate or 1- (3,5-dichlorophenyl) -3-methoxymethylpyrrolidine-2,5 as a fungicidally active ingredient. -dione or 2,4'-dichloro-1- (ipyrimidin-5-yl) -diphenylmethanol in an amount of 3 to 90% by weight in admixture with cyclodextrin in a quantity of 1 to 90% by weight, wherein the weight ratio of fungicidally active ingredient to cyclodextrin is 49: 1 to 1: 5, preferably (2 to 5): 1, and optionally conventional auxiliary ingredients. 2. The fungicidal composition of claim 1, wherein said cyclodextrin is α-, β, or χ-cyclodextrin. 3. A fungicidal composition as claimed in claim 1, wherein the fungal composition comprises carbamoylibenzimidazole-2-methylcarbamate 1-butyl and cyclodextrin in a ratio of (2 to 5): 1, preferably 3.5: 1.5. 4. A fungicidal composition according to Claims 1 and 2 comprising 2-methoxycarbonylaminobenzimidazole and cyclodextrin in a ratio of (2 to 5): 1, preferably 3: 1. 5. A fungicidal composition according to claims 1 and 2 comprising 1- (3,5-dichlorophenyl) -3-methoxymethylpyrrolidine-2,5-dione and cyclodextrin in a ratio of (2 to 20): 1, preferably 10: 1. 6. A fungicidal composition according to claims 1 and 2 comprising 2,4'-dichloro-1- (pyrimidin-5-yl) diphenylmethanol and cyclodextrin in a ratio of (1 to 100): 10, preferably 1 : 5.