LU81499A1 - HERBICIDE TREATMENT METHOD AND COMPOSITIONS THEREFOR - Google Patents

Description

(· It - i! I t

The present invention relates to a method for controlling weeds in 9 grain crops, as well as herbicidal formulations used in this method.

5 So far, the broad-leaved weed species Matricaria spp has been shown to be particularly resistant to conventional herbicides, causing enormous damage in winter and spring cereal crops such as wheat, barley, oats and 10 rye. Now, the Applicants have found that by using a combination of particular known herbicides, this weed species can be controlled with surprisingly high synergism in accordance with the well known equation of "Colby" ("Weeds "15 * 20-22, 1967) In addition,! 15 it was found that the control of other problematic weed species was very satisfactory using

St I this combination, the synergism being observed again in i s I several cases.

Therefore, according to the present invention, a method for combating weeds in cereal fields I consists in applying, to these fields and after the emergence of the harvest, a compound of formula I: | 0

II

ch3o-c Cl 02n- ^ 0 - Cl (I) • and one or more compounds of formula XI: ch3 • * ° f \

Cl- (f Λ-0-X-C00H (II)

Where X represents a group -CH (CH3) -, a group -CH ^ - or a group - (CE ^) ^> when a compound of formula II is used in which X represents a group -CH (CH3) - , the compound of formula I is applied at a rate of 0.25 to 3 kg / hectare, while i the compound of formula II is applied at a rate of 0.5 to 3 kg / hectare; when using a compound of formula II in which X represents a group -CHL-, the compound of formula j 40 I is applied at a rate of 0.7 to 2 kg / ha, while the compound of formula II is applied at a rate of 0.7 to 3 kg / ha and, when using a compound of formula II in which X represents a group - (CE ^) ^ “;” the compound of formula I is applied at a rate of 0.25 to 3 kg / ha and the compound of formula 5 II is applied at a rate of 0.1 to 3.5 kg / ha, the crop not being a crop of spring wheat when a single compound of formula II is used in which X is a group.

Generally, the compound of formula I is applied at a rate of 0.7 to 2 kg / ha, while the compound (s) of formula II is or are applied at the rate of 0.7 to 3 kg /Ha.

The compound of formula I is known as "Bifenox", the preparation of which is described in British Patent No. 1,232,368 and the use of which as a herbicide "is described in" Proc. NE Weed Sci. Conf. " 1973 ^ 2_7d 31 ·

The compound of formula II in which X is a group -CH (CH3) - is known under the name of "Mecoprop".

The compound of formula II in which X is a group --CE ^ - is known as "M.C.P.A.".

The compound of formula II in which X is a group ~ (CH0) 0- is known under the name of "M.C.P.B.".

Literature abounds in documentation concerning "Mecoprop", "M.C.P.A.", "M.C.P.B.", their salts and their esters, as well as with regard to their preparation and their herbicidal px-properties.

The compounds of formula II can be used in the form of free acids or also in the form of salts or esters which are not phytotoxic with regard to cereals.

Among the salt forms, there may be mentioned, for example, the alkali metal salts, in particular the sodium and potassium salts, as well as the ammonium, alkylammonium and alkanolammonium salts , for example, the ethanol-ammonium salts. Among the esters, mention may be made of lower alkyl esters (for example, those containing 1 to 8 carbon atoms), in particular methyl and octyl esters. The use of these salts and esters is within the scope of the present invention.

In the process of the present invention, the 40 / compound of formula I ("Bifenox") is preferably applied ί I "3 I. at a rate of 0.7 to 1.5 kg / ha, better still , about

ί 0.75 to 1 kg / ha. The compound of formula II in which X

4 m i is a group -CHCCH ^) - or a group - (Cll ^) ^ -. " that is to say

Ile "Mecoprop" or "M.C.P.B." is applied, preferably, at a rate of 1 to 2 kg / ha. The compound of formula II in which X is a group -CB ^ -, that is to say the "MCPA", is preferably applied at a rate of 0.7 to 1.5 kg / ha, better again, at a rate of approximately 0.75 to 1 kg / ha.

The weight ratio between the compound of formula 10 I and the compound (s) of formula II is generally ä! in the range of 1: 4 to 3: 1 · When using "Bifenox" I - together with "Mecoprop" or "M.C .P .B.", the ratio pon- | between the first and the second is preferably in | the range from 1: 3 to 1.5: 1 * better still, about 1: 2.

When using "Bifenox" with "MCPA", the overall ratio between the first and the second is preferably in the range of 1: 2 to 2: 1, more preferably, to about 1: 1.

In the case of the compounds of formula IX, the ratios; The above-mentioned weight ports are based on the acid equivalent of these compounds if a salt or ester is used.

, It is best to carry out the process of the; present invention when the harvest is between the stage of a leaf and the appearance of the second node.

The crops which it is preferable to treat t i by the process of the present invention are winter wheat, spring barley and winter barley.

"The compound of formula I and the compound (s) of formula II can be applied together or separately.

In the latter case, the period of time between the applications is preferably short, for example, one day or less. However, it is far preferable to apply the compounds simultaneously as a single formulation. In order to simplify the preparation, storage and transport, the herbicidal formulations are normally prepared in the form of concentrates intended to be diluted in water to the degree required to obtain the application rates mentioned above. These concentrate formulations can contain $ 1 to $ 90, preferably $ 15 to $ 85 by weight of active ingredients 40 associated with one or more inert carriers and not phytotoxic for these ingredients. These formulations are usually in the form of a wettable powder, an emulsifiable concentrate or even in the form of a suspension or an aqueous solution.

Another aspect of the present invention is herbicidal formulations. Thus, a herbicidal formulation is intended to be used in the process of the invention, optionally after dilution if necessary, this formulation comprising a compound of formula I and one or more compounds of formula II or one of their salts or esters in a weight ratio ranging from 1: 4 to 3: 1 (based on the acid equivalent of the compound or compounds of formula II) together with a support or a non-phytotoxic thinner. The preferred weight ratios are within the ranges indicated above. * In another distinct aspect of the present invention, a herbicidal formulation is provided comprising a compound of formula I (indicated above) together with a compound of formula II in which X is a group - (CH ^) ^ - 20 or one of its salts or esters in a weight ratio ranging from 1: 4 to 3: 1 (based on the acid equivalent of the compound of formula II) and with a non-phytotoxic carrier or diluent. In this case also, the preferred weight ratios are within the ranges indicated above.

The herbicidal formulations of the present invention include not only so-called concentrate formulations, but also dilute ready-to-use formulations such as tank mixes and 30 liquors for spray application. These diluted formulations are generally prepared by diluting concentrate formulations to the appropriate degree, but can optionally be prepared by separate addition of appropriate amounts of the individual components to an adequate diluent or carrier.

Referring now to the concentrate formulations, the wettable powders consist of an intimate mixture of the active ingredients, one or more inert carriers and one or more suitable surfactants. The inert support can be chosen from clays 40, d1 attapulgite and montmorillonite, diatomaceous earth,. 5

Jf kaolins, micas, talcs and purified silicates.

Effective surfactants can be found among sulfonated lignins, naphthalene sulfonates and condensed naphthalene sulfonates, alkyl succinates, alkylbenzene sulfonates, alkyl sulfates and surfactants nonionic such as phenol adducts to ethylene oxide. Examples of wettable powders are those having the following composition:

WETABLE POWDERS

10% by weight

Compound of formula I 1 to 73 I Compound of formula II * 1 to 79

Surfactant (s) 1 to 10

Dispersing agent 0 to 10 15 Bulking inhibiting agent 0 to 10. Inert support (s), to complete to 100.

* based on the acid equivalent.

The emulsifiable concentrates consist of active ingredients dissolved in one or more suitable solvents, together with a surfactant. Among suitable solvents, there may be mentioned, for example, benzene substituted with an alkyl group, 1-chlorotoluene, heavy aromatic naphthalenes, glycol ethers and cyclic ketones. Examples of emulsifiable concentrates are those having the following composition:

EMULSIONABLE CONCENTRATES

% w / v

Compound of formula I 1 to 55

Compound of formula II * 1 to 60 3 © Surfactant (s) 2 to 10

Co-solvent 0 to 40

Solvent, to make up to 100 * based on the acid equivalent.

w

The aqueous suspensions and solutions consist of the active ingredients in suspension or in solution in water together with any other desired product chosen from surfactants, thickeners, antifreeze agents or preservatives . The suitable surfactants can be chosen 40 · / from those mentioned above in connection with wettable powders 6! i

When used, the thickening agents are normally selected from natural gums and suitable cellulosic materials, while glycols are generally used when an antifreeze agent is required.

Preservatives can be chosen from a wide range of materials such as various paraben-based antibacterial agents, phenol, o-chlorocresol, phenyl-mercuric nitrate and formaldehyde. Among the aqueous suspensions, there are, for example, those having the following compositions:

AQUEOUS SUSPENSIONS

% w / v

Compound of formula I 4 to 59

Compound of formula II * 5 to 65 15 Wetting agent 0 to 10 »Dispersing agent 0 to 6

Thickening / suspending agent 0 to 5

Antifreeze agent 0 to 15

Preservative 0 to 2 20 Water, to make up to 100 * on the basis of the acid equivalent.

It is preferable to use aqueous suspensions and wettable powders in the process of the present invention because they are much less phytotoxic to cereal crops than emulsifiable concentrates.

The following examples further illustrate the invention. In all these examples, the amounts of "Mecoprop", of "M.C.P.A." and "M.C.P.B." used are 3Ö based on the acid equivalent.

EXAMPLES 1 to 5

The following wettable powders are prepared, each containing the ingredients indicated:% by weight 35 (1) "Bifenox" 20 "Mecoprop" (potassium salt) 40

Sodium lauryl sulfate 3

Sodium lignosulfonate 3 / precipitated silica 8 40 Kaolin, to make up to 100%. 7?

S

\ ·. % by weight | (2) "Bifenox" 20 \ * "Mecoprop" (sodium salt) 27 t.l j Alkylphenol ethoxylated 4

Lignosulfonate 3 5 Smoked silica 6

Attapulgite, to make up to 100% by weight (3) 11 Bif enox "10 n Mecopropn (diethanolamine salt) 25 10 Sodium salt of condensed naphthalene sulfonic acids 6

Precipitated silica 10

Sodium aluminosilicate, to complete to 100% by weight ¥ 15 (4) "Bifenox" 30 days "M.C.P.B.11 (sodium salt) 45 I 'Sodium lauryl sulfate 2

AT

! Sodium lignosulfonate 3

Precipitated silica 5 I 20 Montmorillonite, to make up to 100 ij i% by weight (5) "Bifenox” 30 (sodium salt) 30

Sodium lauryl sulfate 2 25 Sodium lignosulfonate 3

Precipitated silica 5 I Montmorillonite, to complete to 100.

In each example, the active ingredients are carefully mixed with the excipients specified in conventional mixing equipment. Then, in a fluidization energy mixer, the mixture with a xular granularity of between 1 and 10 microns is further ground.

I r EXAMPLES 6 to 10 »35 The emulsifiable concentrates below are prepared hereinafter containing the constituents indicated:

! I

8% w / v (6) "Bifenox’1 15" Mecoprop11 30

Calcium dodecyl-benzene-sulfonate 3

Alkyl-phenoxypolyoxyethylene-ethanols 3 5 Isophorone 20

Xylene, to complete to 100% w / v (7) "Bifenox” 15, Ester of · ηΜβοορΓορπ 20

Alkyl-aryl-sulfonate 4

Polyoxyethylene triglyceride 4

Cyclohexanone 20

Orthochlorotoluene, to complete 100% w / v 15 (8) "Bifenox" 10 "Mecoprop * 1 25

Lucid dodecylbenzene sulfonic amine salt 3

Polyoxyethylene sorbitol fatty esters 4 20 Isophorone 15

Heavy aromatic naphtha, to complete 100% w / v (9) "Bifenox” 20 "M.C.P.B.11 (mixed butyl esters) 30 25 Calcium dodecylbenzene sulfonate 3

Alkyl-phenoxypolyoxyethylene-ethanols 4 - Isophorone 30

Orthochlorotoluene, to complete 100% w / v 30 (lO) "Bifenox” 20 “M.C.P.A.“ 20

Calcium dodecylbenzene sulfonate 3

Alkyl-phenoxypolyoxyethylene-ethanols 4

Isophorone 30 35 Orthochlorotoluene, to supplement 100

The active ingredients are added to the appropriate solvent (s) while stirring and optionally while heating in order to facilitate the dissolution of the active ingredients. Next, f / the surfactants are added. We then filter the solutions EXAMPLES 11 to 13! The following aqueous suspensions are prepared! containing the constituents indicated: 9% by weight I! 5 (il) "Bifenox" 30 "M.C.P.A." (amine salt) 30 (Ethyl) -hydroxyethyl cellulose 0.2

Lignosulfonate 3

Propylene glycol 2 10 Water, to complete to 100 fa by weight (12) "Bifenox" 20 "M.C.P.B." (amine salt) 35

Hydroxyethyl cellulose 0.2 15 Amine ethoxylate 3 * Water, to make up to 100 • $ by weight (13) »Bifenox» 25 "Mecoprop" (amine salt) 50 20 Hydroxyethyl cellulose 0.5

Phosphate ester 3

Ethylene glycol 2

Water, to make up to 100

The following examples serve to illustrate the synergistic effect exerted by the process of the invention.

EXAMPLE 14

Several trials were carried out on winter wheat fields and one trial on a spring barley field in soils of sand and clay potting soil. Using a backpack sprayer tank mixes were applied in a volume of 300-800 liters / hectare.

The stage reached by the crops at the time of application was between the start of tillering and the stage at which the second node was visible. Visual assessments of herbicidal activity were carried out two to fifteen weeks after application using the Barratt and Horsfall (1945) rating system.

The table below shows the average of the I results obtained in terms of percentage of control of 40 the weed species Matricaria spp for the herbi- I * 10 individual cides nBifenox ”,” Mecoprop ”and” MCPA, ”, of same as for tank mix combinations of • 'Bifenox + Mecoprop ”and” Bifenox + MCPA ”, while also indicating the control value evaluated by formula 5 of” Colby! I for the additive effect. The concentrates from which the aqueous spray liquors were formed were an 80% wettable powder of "Bifenoxn, a 55% aqueous solution of" Mecoprop "and a 40% aqueous solution of" M.C.P.A. ".

10 TABLE

. Rate of Percentage Control Percentage Observed According to __ (kg / ha) ___ "Colby1 15" Bifenox ”1.0 1.0 16.1 None '' Bifenox” 1.5 25.5 None 11 Bif enox ”2.0 40 , 3 None "MCPA" (amine salt) 0.8 38.5 None ”MCPA” (amine salt) 1.6 64.8 None 20 "Mecoprop" (amine salt) 2.0 54 * 8 None "Bifenox + MCPA" (amine salt) 1.0 + 0.8 85, 1 48.4 "1.5 + 0.8 93.4 54.2 25" 2.0 + 1.6 95.3 79.0 "Bifenox + Mecoprop” (amine salt) 1.0 + 2, 0 86.0 62.1 '”1.5 + 2.0 89.0 66.3 30 Therefore, from the table above, it can be seen that an authentic synergistic effect is observed when adopts the method of the present invention.

There was a slight burn of crop 35 which then germinated on the ground ·

In addition to the excellent control they exert over the weed Matricaria spp, the above tank mixtures have also, in separate trials, exercised excellent control (over 80 ^) over 40 weed species following: Anethum graveolens, Capsella b - 11 bursa-pastoris, Centaurea cyanus, Fumaria officinalis, Lamium ', amplexicaule, Papayer rhoeasj Silene spp and Stellaria media ": In addition, the combination" Bifenox + MCPA " exercised good control (more than 80/5) on the bad herbs of the following species: Anagallis arvensis, Chenopodium album, Polygonum aviculare, Ranunculus arvensis, Ranunculus repens, Raphanus raphanistrum, Rumex crispus, Sinapis arvensis, S onchus arvensis and Veronica hederifolia.

In addition, the combination "Bifenox + Mecoprop11. 10 exerted good control (more than 80 ^) on the species Galium aparine.

EXAMPLE 15

The greenhouse test described below was carried out in order to determine the effectiveness of the combination "Bifenox + 15" M.C.P.B.

I_ PROCESS

Seeds: Galium aparine

Matricaria recutita Veronica persica s 20 Crash: 0.5 cm deep J (Matricaria sp: slight overlap); Temperature / lighting: greenhouse (cold)

Watering: if necessary Fertilization: none 25 Type of experience: block taken at random (four replicas)

Dimensions of treated lots: 10 x 10 cm pots Soil texture: potting soil

Application equipment: micropulverizer with a single nozzle at band width: 50 cm; applied volume: 50 ml / m2.

Weed stage at time of application - 3 to 5 actual leaves *

The table below shows the average of the results obtained in terms of percentage of control of the weed species I, together with the control value evaluated according to the "Colby" formula. For the species "Veronica persica", a visual control evaluation was carried out. For the other two species, we took the weight of shoots: 40 recent.

i i

12

The "Bifenox" from which the spray liquor was formed, was an 80% wettable powder, "M.C.P.B." was an aqueous solution while the combination was a tank mix · 5 _______

Rate Percentage control of weed application species _ cation Matricaria Sp Galium apa- Veronica (kg / ha) rine persica 10 ____

Obser- Sui- Obser- Sui- Obser- Next before before before "Colby" »Colby" »Colby 15" Bifenox "0.75 56.5 None 62.5 None 77.0 None» M.C.P.B. » 1.0 7.5 None 0.0 None 73.0 None "M.C.P.B." 1.5 2.4 None 0.0 None 78.0 None "Bifenox + 20 M.C.P.B." 0.75 + 1.0 73.0 60.0 72.1 62.5 100.0 94.0 "0.75 + 1.5 82.0 57.5 78.3 62.5 100.0 96, From the above table, therefore, it can be seen that an authentic synergistic effect is observed when adopting the process of the present invention.

EXAMPLE 16

This example further illustrates the syner-gic effect exerted by the combination "Bifenox + Mecoprop" when used for the control of the broad-leaved weed "Matricaria spp".

Winter wheat was sown in France in October at a depth of 3 cm. and at a rate of 150 kg / ha. The crop was allowed to grow untreated Until the following March, when the crop reached growth stage 4-5 (see "Plant Pathol.", 3., 128-9 (1954)) ·

"Bifenox" and "Mecoprop" were then applied separately and in combination as a tank mixture by spraying them onto the area in which

J

- 13 '. the crop was growing, using a | sprayer carried on the back, at a volume of 300 liters / hectare.

j Determinations (weed control assessments) were performed two to five weeks after application.

BOARD

Dosage applied Percentage of con- (g / hectare) weed control Matricaria spp 10 "Bifenox” 1.000 6 "Bifenox” 1.500 15. “Bifenox + Mecoprop” 1.000 + 2.000 87 “Bifenox + Mecoprop” 1.500 + 2.000 88 “Mecoprop” 2.000 50 15 AT I ^ V 1 day i

Claims (18)

14. ‘CLAIMS 1. Method for combating weeds in a cereal field, characterized in that it consists in applying, to this field and after the emergence of the harvest, a compound of formula I: 0 CHo0-C Cl o2n-J-0- ^ ^ -Cl (I) and one or more compounds of formula II: _ / CH3 Cl- {3- 0 ~ X “COOH (il) where X represents a group -CHCCH ^) -, a group -CH ^ - or a group - (CH ^) ^ “and7 when using a compound of formula II in which X is a group -CHÎCH ^) -, the compound of formula 20 I is applied at a rate of 0.25 at 3 kg / ha and the compound of formula II is applied at a rate of 0.5 to 3 kg / ha; when using a compound of formula II in which X is a group -CH ^ -, the compound of formula I is applied at a rate of 0.7 to 2 kg / ha and the compound of formula II is applied at a rate of 25 0.7 to 3 kg / ha and, when using a compound of formula II in which X is a group - (CH0) „-, the compound of formula I is applied at a rate of 0.25 to 3 kg / ha , while the compound of formula II is applied at a rate of 0.1 to 3 ^ 5 kg / ha, the crop not being a crop of spring wheat 3Ö when a single compound of formula II is used in which X is a group -CH (CH ^) -. 2 »Process according to claim 1, characterized in that the compound of formula I is applied at a rate of 0.7 to 2 kg / ha, while the compound or compounds of formula II is or are applied at a rate from 0.7 to 3 kg / ha. 3. Method according to any one of claims 1 and 2, characterized in that the compound of formula / I is applied at a rate of 0.7 to 1.5 kg / ha. j 4 15 i * 4. Method according to any one of claims 1 to 3 j characterized in that, in the compound of formula XX, X is a group -CH (CH ^) -. 5 · Process according to any one of REVEN-5 dications 1 to 3, characterized in that, in the compound of formula II, X is a group - (CH9) -. 6. Method according to any one of claims 4 and 5j characterized in that the compound of formula II is applied at a rate of 0.7 to 1.5 kg / ha. 7. A method according to claim 6, characterized in that the compound of formula II is applied at a rate of 0.75 to 1 kg / ha. 8. Method according to any one of claims 1 to 3; characterized in that, in the compound of formula II, X is a group -Cth ^ - · 9 · A method according to claim 8, characterized in that the compound of formula II is applied at a rate i. from 0.7 to 1.5 kg / ha. i! 10. Process according to any one of Claims 4 and 5, characterized in that the weight ratio between the compound of formula I and the compound of formula II is in the range of 1: 3 to 1, 5: 1. i * 11. The method of claim 8, characterized in that the weight ratio between the compound of formula I and the compound of formula II is in the range of 1: 2 to 2: 1. 12. Method according to any one of claims 1 to 11, characterized in that the harvest is one. harvest of winter wheat, spring barley or winter barley. 13 · Method according to any one of the res- Dications 1 to 12, characterized in that a liquor formed on the crop is sprayed on by adding water to a formulation of an aqueous suspension or a wettable powder containing the compounds corresponding to formulas I and II. 14 · A method according to any one of claims 1 to 13, characterized in that the processing of the harvest takes place when it has reached a stage lying between that of a leaf and the appearance of the second node. I 40! .. 16 15. Method according to any one of the resales | Dications 1 to I4j characterized in that the compound of formula * II is a salt or a non-phytotoxic ester with respect to cereal crops. 16. The method of claim 1, substantially as described in the above specification. 17. A herbicidal composition comprising a compound of formula I according to claim 1 and a compound of formula II also according to claim 1, which is used at application rates and in crops as indicated in claim 1, the ratio by weight between the compound of formula I and the compound of formula II lying in the range from 1: 4 to 3: 1 * 18. Composition according to Claim 17, characterized in that, in the compound of formula II, X is _ a group -CH (CHg) - · 19 * Composition according to Claim 17; " characterized in that, in the compound of formula II, X is a group -CH ^ -. 20. Composition according to Claim 17 * characterized in that, in the compound of formula II, X is a group - (0112) 2 “· 21. A composition according to any of claims 17 to 20 in the form of an aqueous suspension or a wettable powder. 22. Herbicidal composition comprising a compound of formula I according to claim 1 together with a compound of formula II also according to claim 1 and • t wherein X is a group - (CH ^) ^ “· 23. Composition according to any one of claims 17 to 22, characterized in that the compound of formula II is a salt or a non-phytotoxic ester with respect to cereal crops. - · * · ν. . ''