DD231714A5 - PLANT PROTECTION AGENTS AND METHODS OF CONCENTRATING SCHAEDLINGEN AND UNKRAEUTERN - Google Patents

Abstract

The invention relates to novel crop protection compositions containing as active ingredient compounds of general formula (I) wherein X is hydrogen, an alkali metal or an alkaline earth metal, an alkyl or alkenylcarbonyl group having 1-10 carbon atoms, an optionally halogen-substituted phenylcarbonyl or a Group of the general formula H HNR1R2R3 stands in which R1, R2 and R3 are independently hydrogen, an alkyl, an alkoxyalkyl, an alkenyl, a hydroxyalkyl, a cycloalkyl or an optionally substituted phenyl group. The invention further relates to a method for controlling pests and weeds. Formula I

Description

Field of application of the invention

The invention relates to a plant protection product and a method for controlling pests and weeds. Characteristic of the known technical solutions

It is known that the 2-methyl-4,6-dinitrophenol (dinitro-ortho-cresol, DNOC) and its alkali metal salts have a herbicidal and acaricidal activity. Compositions containing this substance as an active ingredient are, for. B. Novenda and cresonite. Another well-known herbicide is 2-sec-butyl-4,6-dinitrophenol (DNBP), a dinitro-ortho-cresol-related compound that can also be used as a biostimulator in maize crops in smaller doses (Ohlrogge, AJ: The Development of DNBP [Dinoseb] as a Biostimulant for Com in Plant Growth Regulator; Editor: Stutte CA 79-87 pp Advances in chemistry series; 159 American Chemical Society, Washington, 1977).

In GB-PS 1378994 the preparation of 2,4-bis (trifluoromethyl) -6-nitrophenols and its derivatives is described. The preparation of 2,6-dinitro-4-trifluoromethylphenol and its derivatives is described in U.S. Patent 3,813,446. These known processes are carried out in organic solvents, if appropriate in the presence of a phase transfer catalyst. In this case also run off unwanted side reactions, for example, the formation of ether derivatives in methanolic medium, or the hydrolysis of the trifluoromethyl group to the carboxyl group.

Aim of the invention

The invention is intended to provide novel pesticidal compositions having herbicidal, acaricidal and growth-regulating effects.

Explanation of the essence of the invention

According to the invention, the novel agents contain, in addition to customary auxiliaries and excipients, as active ingredient a compound of the general formula (I) in which

X is hydrogen, an alkali metal or an alkaline earth metal, an alkyl or alkenylcarbonyl group having 1 to 10 carbon atoms, an optionally substituted by halogen phenylcarbonyyl or a group of the general formula

HNR ₁ R ₂ R ₃

stands,

in which R ₁ , R ₂ and R ₃ independently of one another represent hydrogen, an alkyl, an alkoxyalkyl, an alkenyl, a hydroxyalkyl, a cycloalkyl or an optionally substituted phenyl group.

These compounds can be prepared by preparing the corresponding alkali or Erdaikaliphenolat in the first step from 2-chloro-3,5-dinitro-benzotrifluoride by reacting with an alkali or alkaline earth metal hydroxide. The reaction is conducted without a catalyst in an aqueous medium at 20-100 ⁰ C, preferably at 60-80 ° C, and a sud concentration of 5-20Gew .-%, preferably 10-15Gew .-% executed. The phenolate obtained in the hydrolysis can be converted into the phenol derivative by means of an acid in a manner known per se. If desired, another compound of general formula (I) can be prepared from the resulting phenol (X = H) by reaction with a corresponding base. The compounds of the general formula (I) are isolated from the reaction mixture and can then be further processed into crop protection agents. For this purpose, the carrier, extenders and auxiliaries which are generally customary in crop protection are used. The shape of the composition is selected according to the purpose of use. Depending on the mode of application and the type of agent, the compositions preferably contain 0.1-80% by weight of active ingredient. The formulations are used in crops for the destruction of pests or for the regulation of plant growth.

embodiments

The invention will be explained in more detail with reference to the following examples, but is not limited to these examples.

example 1

60% by weight emulsion concentrate (EC60)

433g 2-trifluoromethyl-4,6-dinitrophenol (97%) are dissolved at 40 ⁰ C in a mixture of 200 g of isophorone, and 25 g of xylene.

The solution is cooled to room temperature and filtered through a GAF filter of pore size 0.1 μπι . 36 g of Tensiofix B7425 and 6 g of Tensiofix LS are added to the filtrate as an emulsifier with stirring.

Example 2

60% strength by weight emulsion concentrate (EC60)

The procedure described in Example 1, but using instead of isophorone cyclohexanone and instead of xylene, the solvent aromatol. The emulsifiers used are the products mentioned in the following table.

Emulsifier: A B C

TensiofixAS -18 - 10

TensiofixLS 24 - -

Emuisogen EL - - 12 25

SapogenatT180 - 10 -

Sapogenate T500 - 20 7

Example 3

20% by weight water-soluble concentrate (WSC20)

To 300 g of a 30% strength aqueous solution of 2-trifluoromethyl-4,6-dinitro-sodium phenolate, 50 g of ethylene glycol and 4 g of Tensiofix CG-21 are added as emulsifier. The solution is made up to 450g with desalted water while stirring

Example 4

20 wt .-% oily paste

620 g of 2-trifluoromethyl-4,6-dinitrophenol are dissolved in 500 g of cyclohexanone and added to the solution 120 g of cosmetic Vaseline oil. With the aid of an Ultra-turrax mixer, the resulting solution is emulsified with a 10% solution of the emulsifier Tensiofix PO-132, wherein the temperature is maintained at 30 ⁰ C. The mixture is cooled to 15 ⁰ C. Within one hour, the 0.2% solution of Kelsan S in ethylene glycol in an amount of 50 g is distributed in the mixture with slow stirring.

effect studies

Example 5

Examination of the herbicidal effect in the greenhouse

The seeds of white mustard, curly amaranth, white goosefoot (reporting), Italian fennich, winter wheat and corn were sown in seed pots. After emergence, the plants were sprayed in the 2-4 leaved stage with 0.2% spray liquor (prepared by diluting 10% EC and WSC preparations prepared from the test compounds), each compound being applied in the amounts of 2.5 5 and 10 kg / ha was tested. On the 14th day after the treatment, the damage to the plants was determined in percent. The results are summarized in Table 1.

Table 1

connection dose mustard Amaranth goosefoot Fennich wheat Corn kg / ha 2-trifluoro-methyl-4,6-Dini 1.25 45 50 75 0 0 0 trophenol 2.55 75 85 90 10 5 5 5.0 95 100 100 30 10 15 2-trifluoro-methyl-4,6-Dini 1.25 40 50 70 0 0 0 trophenol diethanolamine 2.5 60 60 75 - - - 5.0 80 85 , 80 10 10 10 2-trifluoro-methyl-4,6-Dini 1.25 45 50 70 0 0 0 trophenyl-dimethylamine 2.5 55 65 75 0 0 0 5.0 75 80 85 20 10 10 2-trifluoro-methyl-4,6-Dini 1.25 50 60 70 0 0 0 trophenol sodium 2.5 80 85 90 10 0 10 5.0 100 100 100 15 15 15 2-trifluoro-methyl-4,6-Dini 1.25 '65 45 70 0 0 0 trophenolkalium 2.5 75 85 90 10 0, 10 5.0 90 100 100 15 15 15

Example 6

Determination of inhibition of the Hill reaction

By means of the method of Arnon u. a. were isolated from spinach chloroplasts. To one gram of the strains of purified spinach leaves was added 6 ml of 0.35 molar saline and 0.6 ml of 0.2M TRIS buffer. The whole was ground, filtered through several layers of gauze and then centrifuged at a speed of 2000 for 5 minutes. The cloroparene precipitate was suspended in 0.035 molar saline, homogenized in the Potter tube, and the resulting chloroplast suspension stored at 0 ° C until use.

From the Chlöroplast suspension and K ₃ Fe (CN) ₆ , K ₂ HPO ₄ , TRIS. HCI buffer and MgCl ₂ , a mixture is prepared. To this are in the concentration range from 10 ^-10 to 10 ^-3 mol prepared solutions of the compounds of general formula (I) (as inhibitors) or as standard substances corresponding solutions of N- (3,4-dichlorophenyl) -N ', N-dimethylcarbamid (DCMU) and dinitro-ortho-cresol (DNOC). The resulting mixtures are exposed for 20 minutes to an illuminance of 5000 lux. Then the reaction is stopped by the addition of 25% trichloroacetic acid (TCA). The precipitate is removed by centrifugation and the absorbance of the solution is measured at 420 nm with a Spectrophotometer 204 spectrophotometer. The series of measurements is repeated with samples kept in the dark. The inhibition of the Hill reaction was determined by the difference in absorbance of light and dark samples and converted to μg / ml of malium ferrocyanide by a calibration curve. (The percentages of inhibition

were plotted as a function of concentration, and from the curve the concentrations corresponding to a 50% inhibition were read ( _I50 ).)

The results are shown in Table 2.

Table 2

connection

l ₅₀ (micromoles / dm ³ )

2-TrifIuormethyl-4,6-dinitrophenol

2-trifluoromethyl-4,6-dinitrophenol-diethanolamine 2-trifluoromethyl-4,6-dinitrophenol-dimethylamine 2-trifluoromethyl-4,6-dinitrophenol-NH ₄

2-trifluoromethyl-4,6-dinitrophenol-Na

2-trifluoromethyl-4,6-dinitrophenol-K

Comparison substances:

Dinitro-ortho-cresol-Na

N- (3,4-dichlorophenyl) -N ', N'-

dimethylcarbamid

0.21 0.57 0.52 0.25 0.20 0.31

0.86 0.071

From these data it can be seen that 2-trifluoromethyl-4,6-dinitropheno! and its salts are similar to the N- (3,4-dichlorophenyl-N'.N'-dimethylcarbamide) inhibitors of the second photochemical system and their effectiveness is approximately between that of N- (3,4-dichlorophenyl) -N ', N' Of the compounds used as the active ingredient in this test, the amine salts show less activity than the alkali and ammonium salts.

Example 7

Examination of the herbicidal activity on maize (field) The investigations were carried out using the 2-trifluoromethyl-4,6-dinitrophenol-Na WSC20 formulated according to Example 3 or the 2-trifluoromethyl-4,6-dinitrophenol EC60 formulated according to Example 1. On 25726.April, corn kernels of the variety Pioneer 3950 were seeded in brown forest soil containing 1.8% organic substances with a germ count of 73000 / ha 8-10cm deep. On May 30, sprayed with a Parzellensprühvorrichtung (spray head tea jet 11002,1,5atm pressure) and a water application rate of 300 liters / ha. At this time, most corn plants had 3-4 leaves, most weeds had 2-4 leaves. Each composition was tested in four parallel experiments. At the time of treatment, the area was 87.5% covered with weeds. Of these, 58% were amaranth, 27% goosefoot and the remainder ranunculus. The effect was evaluated on 15 June. The herbicidal activity on the weeds and the phytotoxic effect on the maize were determined using the EWRC scale.

Table 3 shows the rating scale, in Table 4 the results are summarized. Each value is the mean of 4 parallel experiments.

Table 3

EEA - Value Scale

value weed Devastating ~ - destruction EWRC values for different plants Damage to the in percent 0 Well 20 WSC ul 10 l / ha CJL phenol-60EC 3.2 l / ha effect % crops % 1 5 l / ha 1.5 1.5 1.61 / ha 2 1 excellent 100 none 2 3 1 4 1 2 excellent 99 very weak 5 white goosefoot 2 2 3.5 3.5 3 Well 98 weak 10 Echinochloi 7 1 4 satisfactory 95 weak to moderate 25 Corn 1 5 adequately 90 moderate 50 6 insufficient · 75 mediocre 75 7 bad 50 strongly 100 8th very bad 25 very strong 9 unusable 0 complete annihilation Table 4 -. - .._. Active substance and dose 2-trifluoromethyl-4,6-dinitrophenol-2-trifluoromethyl-4,6-dinitro- plant Amaranth

Example 8

Growth and earnings support for corn On April 20, maize of the variety MVSC 3780 with a germ count of 55,000 / ha was sown. At the beginning of flowering on July 22, a helicopter was sprayed with 2-trifluoromethyl-4,6-dinitrophenol-Na (20WSC). The application rate was 0.25 liters / ha (= 0.05 kg / ha). Each of the two parallel experiments was carried out on a 4-hectare plot. Per

Hectares were used 50 liters of water. The corn was harvested on 3 November. The results are summarized in the following Table 5.

Table 5

parameter Trial I Try Il control Piston length, cm 16.08 ± 2.19 17.06 ± 2.71 17.33 ± 1.87 Share of not completely with Grains occupied flask,% 62 66 84 Part occupied with grains of the piston cm 14.52 ± 2.80 15.35 + 3.93 15.33 ± 2.48 % 90.35 93.34 89.97 Weight of a piston, g 229.6 ± 6 208.4 ± 5 191.6 ± 4 Crop yield, t / ha 4.25 4.08 3.55 in% of control 119.7 114.9 100

The experiments have shown that the 2-trifluoromethyl-4,6-dinitrophenol-Na exerts its yield-increasing effect on larger grains and a better occupation of the piston with grains.

Example 9 Investigation of the acaricidal activity The experiments were carried out on apple trees (Golden delicious) planted at intervals of 7.5 m χ 4.5 m. On March 16, prior to sprouting the sprouts, sprayed from a Haftlinger sprayer with a high pressure spray gun (20 bar), 48 hours after the treatment, 5x10 fruit shoots were collected from each plot, whether treated or untreated (on each plot 5 trees grew) and these in the laboratory observed so long, in the case of the untreated control all Webermilben had hatched out (12.Tag). The mortality was calculated from the number of hatched mites as a percentage of the control. The results are shown in Table 6.

Table 6

composition Conc. hatched dead infestation % Mites (pcs) eggs in the from 5 x 10 shoots % control 2-Trif! Uormethyl-4,6-dinitro- phenol-Na 20 WSC 2.5 19 96.35 3.6 2-trifluoromethyl-4,6-Dini trophenol EC 60 0.8 23 95.59 4.41 Dinitro-ortho-cresol (DNOC-25 ') paste 2.0 27 94.82 5.18 untreated control - 521 0 100

The compounds of the general formula (I) exceed, as the table shows, the effect of the reference substance dinitro-orthocresol (Paste Novenda 25).

O-X

O ₂ M

(I

/ VO:

Claims (3)

-1- 662 11 Invention claim: 1. Plant protection product, characterized in that it contains, in addition to customary excipients and carriers as the active ingredient at least one dinitrophenol of the general formula (I) wherein X is hydrogen, an alkali metal or an alkaline earth metal, an alkyl or alkenylcarbonyl group having 1 to 10 carbon atoms, an optionally substituted by halogen phenylcarbonyyl or a group of the general formula HiNIR ₁ R ₂ R ₃ stands, in the R ₁ , R ₂ and R ₃ independently of one another hydrogen, an alkyl, an alkoxylalkyl, an alkenyl, a hydroxyalkyl, a cycloalkyl or an optionally substituted phenyl group. 2. Plant protection product according to item 1, characterized in that they contain as active ingredient 0.1-80 wt .-% of compounds of general formula (I) and conventional carriers, extenders and auxiliaries. 3. A method for controlling pests and weeds in one place, characterized in that applying to the site a compound of general formula (I) or an agent according to item 1 or 2. For this 1 page formula