AU642986B2

AU642986B2 - Herbicide combination containing aclonifen and at least one substituted urea

Info

Publication number: AU642986B2
Application number: AU73583/91A
Authority: AU
Inventors: Thierry Bernard; Jean-Claude Millet; Jacques Rognon
Original assignee: Rhone Poulenc Agrochimie SA
Current assignee: Bayer CropScience SA
Priority date: 1990-03-20
Filing date: 1991-03-18
Publication date: 1993-11-04
Anticipated expiration: 2011-03-18
Also published as: DE69114746D1; RO111981B1; PL166329B1; FR2659833A1; DK0449751T3; FR2659833B1; YU48391A; MA22086A1; TNSN91015A1; CZ284508B6; PL289473A1; RU2051585C1; PT97075A; AU7358391A; DE69114746T2; IE910912A1; SK281061B6; CS9100725A2; GR3018193T3; EP0449751A1

Abstract

The invention relates to a novel herbicidal association arising from the combination of a) 2-chloro-6-nitro-3-phenoxyaniline or aclonifen, and b) one of more substituted ureas of formula: <IMAGE> of which there may be mentioned, in particular, isoproturon, chlortoluron, dimefuron and methabenzthiazuron. The ratio by weight of a to b is generally between 1/60 and 1.5. This association is especially useful in post-emergence weed control.

Description

S F Ref: 157160 FORM COMMONWEALTH OF AUSTRALIA PATENTS ACT 1952 COMPLETE SPECIFICATION

(ORIGINAL)

FOR OFFICE USE: Class Int Class Class Int Class a

S

S.

S

'S

Complete Specification Lodged: Accepted: Published: Priority: Related Art: Name and Address of Appl1rant: 5505* .Se

S

S@ S S* *S o 4*

S

Rhone-Poulenc Agrochimie 14-20 rue Pierre Baizet 69009 Lyon Cedex 09

FRANCE

Spruson Ferguson, Patent Attorneys Level 33 St Martins Tower, 31 Market Street Sydney, New South Wales, 2000, Australia Address for Service: Complete Specification for the invention entitled: Herbicide Combination Containing Aclonifen and at Least One Substituted Urea The following statement is a full description of this invention, including the best method of performing it known tc me/us 5845/6 Comany callod: RHONE-POU.ENC AGROCHIMIIE

ABSTRACT

Herbicidal combination containing aclonifen and at least one substituted urea.

The invention relates to a novel herbicidal combination which results from combining a) 2-chioro- 6-nitro-3-phenoxyaniline, or aclonifen, with b) one or more substituted ureas of the formula: o N C N SAr O R of which there may be mentioned, in particular, isoproturon, chlortoluron, dimefuron and methabenzthiazuron. The ra.tio by weight of a to b is generally between 1/60 and This combination is particularly useful for controlling weeds post-emergence of the crops.

Herbicidal combination containing aclonifen and at least one substituted urea The present invention relates to a herbicidal product which results from the combination of herbicidal substituted ureas, if appropriate as a mixture, with aclonifen, and which is remarkably suitable for the selective control of weeds in crops.

The invention also relates to the use of the novel product as a herbicide, in particular in the form of a composition, and to a method of controlling weeds in crops with the aid of the product or the composition.

Substituted ureas have been used for a long time for weeding crop areas. From amongst these, the following may be mentioned by way of example: isoproturon, or N,N-dimethyl-N'-(4-isopropylphenyl)urea, for weeding in particular cereal fields, chlortoluron, or N,N-dimethyl-N'-(3-chloro-4-methylphenyl)urea for weeding in particular cereal fields, dimefuron, or N,N-dimethyl-N'-[3-Lhloro-4-(5-tert-butyl-2-oxo-2,3-dihydro-1,3,4-oxadiazolyl -3-yl)phenyllurea, for weeding pea fields and oilseed rape fields, neburon, or N-mrthyl-N-n-butyl-N'-(3,4-dichlorophenyl)urea, for weeding in particular cereal fields, o 0* f

C

S 6 RLF/0032P 2 linuron, or N-methyl-N-methoxy-N'- (3,4-dichlorophenyl)urea, for weeding in particular maize and sunflower fields, methabenzthiazuron, or 1-benzothiazolyl- 2-yl-1,3-dimethylurea, for weeding in particular cereals, beans and peas.

Moreover, aclonifen or 2-chloro-6-nitro-3phenoxyaniline is known, which is a selective herbicide of sunflower and pea crops, and which is usually used 10 at doses above 2 kg/ha.

0* *O S" It is always desirable to improve the action of herbicidal active substances.

The invention for its part therefore proposes a novel combination which results from a limited selection from amongst a virtually infinite number of possibilities and which provides great advantages which will be understood better in the light of what will be described hereinafter.

It has thus been found absolutely 6 unexpectedly that the combination improved in a noteworthy and surprising fashion the respective S isolated action of the two active substances for a 6 certain number of weeds which are particularly harmful in crops. In doing this, it retains the selectivity towards the crops. From this follows therefore an improvement of the spectrum of activity and a possibility of reducing the particular dose of each active substance used, this latter quality being especially important for ecological reasons which can be readily understood.

The combination thus shows a remarkable eegree of synergism, as defined by PML Tammes, Netherlands Journal of Plant Pathology, 70 (1964), p. 7380, in an article with the title "Isoboles, une representation graphique de synergie dans les pesticides" [Isoboles, a graphic representation of synergism in pesticides], or as defined by Limpel, P.H. Schuldt and D.

,,10 Lamont, 1962, Proc. NEWCC 16: 48-53, according to the 0 S formula (used by Colby):

XY

t vE X Y-- S* 100 0.

where E is the expected percentage of growth inhibition by a mixture of the two herbicides at defined doses, X is the observed percentage of growth inhibition of herbicide A at a defined dose, Y is the observed percentage of growth inhibition of herbicide B at a defined dose. If the observed percentage of inhibition of the combination is greater than E, Sw synergism is present.

0 Moreover, it has been found entirely unexpectedly that, at a dose which as such is not herbicidal from an industrial point of view (that is to say, with an effectiveness which is zero or insufficient), aclonifen considerably increased the strength of, or amplified, the herbicidal effect of 4 suibstituted ureas. This case therefore concerns a noteworthy innovation as far as its consequences with respect to the application methods of the said ureas are concerned.

The invention relates to a product which results from the combination of: a) alconif en with b) one or more substituted ureas of the formula .R4 Ar 0 R I14:. in which Ar is a ring of the formula 00 6R. 0 R, being selected tromn amongst (CI-C3) alky. radicals, alkoxy radicals, a chlorine atom, a *ses bromine atom, a~ 5-tert-butyl-2,3-dihydro-2-oxo ,3,4-oxcadiazol-3-yl group of the forMula (CH3)3 C 0 0 being selected 4rom amongst a hydrogen atom, a chlorine atom, or- l whei= Ar is a ring

R

3 is a hydrogen atom, a (Cl-C 4 alkyl or niethoxy radical,

R

4 is a hydrogen atom or a methyl radical.

When the alkyl or alkoxy radicals comprise at least three carbon atoms, they can be linear or branched.

From amongst the substituted ureas of the formula the following may be mentioned very specifically: isoproturon, or 3-(4-isopropylphenyl)so 1, 1-dimethylurea, 05 chiortoluron, or 3- (3-chloro--p-tolyl) 0 0 at 01, 1-dimethylurea, :00 neburon, or 1-butyl-3-(3,4-dichlorophenyl) 0s e 1-methylurea, diuron, or 3, 4-dichlorophenyl) **woo: 1, 1-dimethylurea.

metoxuron, or 3-chloro-4-methoxyphenyl) 1, 1-dimethylurea, 20 linuron, or 3-(3,4-dichlorophenyl)-l-methoxy- 1-methylurea, o 6 S monolinuron, or 3- (4-chlorophenyl) -l-methoxy- 1-methylurea, methabenzthiazuron, or 1-benzothiazol-2-yl- 1, 3-dimethylurea, metobromuroi., or 4-bromophenyl) -l-methoxy- 1-methylurea, and dimefuron, or 3 -E 4- (5-tert-butyl-2,3-d3±y-dro- 6 2-oxo-1,3,4-oxadiazol-3-yl)-3-chlorophenyl- 1,1-dimethylurea.

In a more advantageous manner and taking into account the previously mentioned problems which the invention proposes to solve, the following will be used: isoproturon, or 3-(4-isopropylphenyl-1,1-dimethylurea, chlortoluron, or 3-(3-chloro-p-tolyl)-l,1-dimethylurea, and methabenzthiazuron, or l-benzothiazolyl-2-yl-1,3-dimethylurea, for weeding in particular cereals, beans and peas.

Accordingly, there is also provided according to the invention a herbicidal composition containing a product of the invention, and at least one inert carrier and/or at least one surfactant.

There is further provided according to the invention a method of controlling weeds post-emergence of crops at a location, wherein an effective dose of the product according to the invention is applied to the location.

These products can be used as herbicides in a ratio by weight of aclonifen and urea which covers a wide range and which will depend in part on the crops treated, the climatic conditions, the nature of the soil, the treatment stage of the principal weeds of the location in question, and even, if appropriate, on the wishes of the user, depending on .whether he wishes the terrain to be perfectly clean or whether he is happy with a satisfactory, but not total, elimination of weeds.

20 These products according to the invention are intended for simultaneous or separate use or use staggered over time for herbicidal treatment of undesirable plants, in particular against weeds which are present in crops. The nature of the crops concerned can vary, depending on the urea in question. This point will be taken up again in the following part which is reserved for the treatment method.

*o IG:\WPUSER\LIBFFI00060:kAR Sof(3 In the case of simultaneous use (which Is preferred), ready-to-use products which contain the combination of active substances described above can be used. Products which are prepared just before application can also be used, by mixing the active substances as they are described hereinafter at the appropriate time.

The user can also use the product by treating the crops to be protected in succession with one and then the other of the active substances, aclonifen and ureas, in such a way as to form the product according to the invention in situ on the plant.

According to a preferred variant, the ratio by weight of aclonifen to urea will be between 6/400 and 2/1, advantageously 1/60 and 1.5/1, and more advantageously 1/30 and 1/1.

The combinations are most frequently of the binary type, but occasionally ternary or quaternary combinations with one or more other compatible pesticides (including fungicide or insecticide) can be envisaged.

As has been indicated previously, one of the problems which the applicant company proposes to solve, is to amplify the action of the ureas. In this case, aclonifen plays the role of poten, ator, or, in the terminology of the discipline of crop protection, of "synergist".

*e 0* C C*

C

o RLF/0032P In this case, according to a preferred variant, the ratio by weight is pre arably between 1/60 and 1.2/1, advantageously 1/60 and 1/2, and very advantageously between 1/30 and 1/3.

The product is therefore defined as a ureabased herbicidal product which contains aclonifen as an amplifier which, per se. is not, or is barely, herbicidal at the dose in question.

Naturally, the variants which are preferred 10 as regards the ureas according to the invention are Sb *S also valid for the present use. It will also be c *c a understood that in the case where aclonifen is the amplifier, chlortoluron and isoproturon will also 0 advantageously be used.

The products according to the invention are mostly used in the form of a herbicidal composition which comprises one or more agriculturally acceptable carriers and/or one or more surfactants.

In the case of the preparations made at the appropriate time, each active substance can be in the form of a composition. In contrast, in the case of a ready-to-use mixture, it ;s the combination itself which is in form of a composition.

In the account which will follow, the terms active substance and combination will be used without distinction.

Occasionally, it is possible to have readily available a ready-to-use composition containing the 9* 09 0 9 .6

S

SE

eq 9 *9 CE

C

I

0e

S

9 combination, given the formulations available on the market, Occasionally, an adequate formulation which is within the scope of those skilled in the art will be in the general description whi~ch will follow, the term "Composition" will thus serve indiscriminately to describe the two compositions containing the two active substances separately or the composition containing the combination.

These combinations which can be used contain, in addition to th~e active substance or the combination according to the invention as described above, solid or liquid carriers which are agriculturally acceptable and al5 surfactants which are also agriculturally acceptable.

0 Substances which can be used in particular are customary inert carriers and customary surfactarits.

These compositions usually contain between and 95% of active substance or combination according to :*20 the invention. Percentages are, unless otherwise specified, by weight.

In the present account, the term "carrier" refers to an organic or inorganic material, natural or 0 synthetic, with which the active substance is combined so ,:25 as to facilita'te application to the plant, the seeds or the soil. This carrier is therefore generally inert and must be agriculturally acceptable, in particular on the treated plant. The carrier can be solid (clays, natural or synthetic silicates, silica, resins, waxes, 55.5

S

5,9

S

*0 OE 5'

S

S C o solid fertilisers, and the like) or liquid (water, alcohols, ketones, petroleum fractions, aromatic or paraffinic hydrocarbons, chlorinated hydrocarbons, liquefied gases, and the like).

The surfactant can be an emulsifier, dispersant or wetting agent of the ionic type. Examples which may be mentioned are salts of polyacrylic acids, salts of lignosulphonic acids, salts of phenolsulphonic acids or of naplthalenesulphonic acids, polycondensates of ethylene oxide with fatty alcohols or with fatty acids or with fatty amines, substituted phenols (in particular alkylphenols or arylphenols), salts of esters of sulphosuccinic acids, taurine derivatives (in 0 particular alkyl taurides), phosphoric esters of a.

15 alcohols or of polycondensates of ethylene oxide with phenols. The presence of at least one surfactant is essential since the active substances (aclonifen urea) are not soluble in water and the application vehicle is water.

20 Types of agricultural compositions which may be mentioned are powders for dusting or dispersion (having a content of compound of the formula which

S

can range up to 100%) and granules, in particular those obcsained by extrusion, by compacting, by impregnating a 25 granulated carrier, by granulation using a powder (the content of compound of the formula in these granules being between 1 and 80% in the latter cases).

Types of liquid compositions, or types which are intended to form liquid compositions when used, which may be mentioned are emulsifiable concentrates, emulsions, flowables, aerosols, wettable powders (or powders for spraying) and pastes.

The emulsifiable concentrates or soluble concentrates mostly comprise to 80% of activn substance, the emulsions, for their part, contain 0.01 to 20% of active substance. The flowables generally contain 10 to 75% of active substance, from 0.5 to 15% of surfactants, from 0.1 to 10% of thixotropic agents and from 0 to 10% of suitable additives such as antifoams, corrosion inhibitors, stabilisers and penetrants.

Moreover, in general, these compositions can also contain a variety of other ingredients such as, for example, thixotropic colloids, penetrants, stabilisers, sequestering agents, and the like, as well as other active substances which are known as having pesticidal properties (in particular insecti:ides or fungicides) or properties which promote the growth of plants (in particular fertilisers) or plant-growth-regulating properties. More generally, the compounds according to the invention can S be combined with all solid or liquid additives which correspond to techniques customary in the art of formulation.

For example, in addition to the solvent, the emulsifiable concentrates can, if necessary, contain 2 to 20% of suitable additives such as stabilisers, surfactants, penetrants, corrosion inhibitors, *00 S RLF/0032P 12 colorants or the abov.ementioned adhesives.

In concrete terms, in the case of the active substances i;a question: aclonifen is available on the market as a flowable containing 600 g/l active substance, isoproturon is also available on the market as a flowable (with between 440 and 500 g/l active substance), chlortoluron can be found in the form of a flowable (between 500 and 510 g/l active substance), wettable powders, granules and microgranules.

A person skilled in the art will easily be capable of formulating a composition based on a t. combination of these active; substances in the form of, for example, a flowable. Moreover, this is the preferred 4@ :15 form of the invention.

Treatment method agcogrding to the jnytion: The invention also relates to a method of controlling weeds, especially in an environment where crops grow, or where it is intended to grow crops, which consists in applying an effective dose of product (or a composition containing it), as has just been described above.

4 e Upon application, the dosage rate should be sufficient for controlling the growth of weeds without causing substantial permanent damage to said crops.

9 Effective dosage rate is understood to mean, only in this context, the dosage rate which allows this result to be obtained.

13 The application is carried out post-emergence of the crops. Post-emergence is understood to mean application of the product after the plant has emerged from the soil.

The product (or composition) according to the invention is mainly active against weeds after they have emerged, even though a pre-emergence action, that is to say when the plant has not yet emerged from the soil, is also possible.

The action of the product (or composition) takes place via the leaves and roots in proportion which may vary depending on the active substances in question.

The product (which can be applied by simultaneous a 4 or separate use or use staggered over time) will normally 15 be applied at a dosage rate ranging from 460 g/ha to coo a 4200 g/ha.

a From amongst the weeds which can be controlled by said product (or said composition), the following may be mentioned: Galium aparine, Avena fatua, Lolium multiflorum, Viola tricolor, Sinapis alba, Lamium purpurea, Veronica persica, Agrostis tenuis, Alopecurus myosuroides, Veronica hederifolia.

*In the following preferred variants: The combination isoproturon/aclonifen will be applied to cereals such as, in particular, wheat and barley. The dosage rate per hectare will advantageously be 14 to 600 g/ha aclonifen and 400 to 3600 g/ha isoproturon, very advantageously: 100 to 500 g/ha aclonifen and 500 to 3000 g/ha isoproturon.

The combination chlortoluron/aclonifen will be applied to cereals such as, in particular, wheat and barley. The dosage rate per hectare will advantageously be: 60 to 600 g/ha aclonit£n and 400 to 3600 g/ha chlortoluron, very advantageously: 100 to 500 g/ha aclonifen and 500 to 3000 g/ha chlortoluron.

The combination dimefuron/aclonifen will be S' applied to cereals such as, in particular, to peas and oilseed rape. The dosage rate per hectare will be, in particular: to 600 g/ha aclonifen and '20 400 to 3600 g/ha dimefuron, very advantageously: 100 to 500 g/ha aclonifen and 500 to 2000 g/ha dimefuron.

The combination aclonifen/methabenzthiazuron will be applied, in particular, to winter wheat and

G

winter barley.

The dosage rate per hectare will be, in particular, 600 to 1000 g/ha aclonifen and 500 to 4000 g/ha methabenzthiazuron and very advantageously: 100 to 500 g/ha aclonifen and 1000 to 3000 g/ha methabenzthiazuron.

The invention will now be described by way of concrete use examples which are, of course, given only by way of example and can in no way limit the scope of said invention.

So as to simplify the method and arrive at a better base for comparison, the following have been selected: Galium aparine, Avena fatua, ."15 Lolium multiflorum, Viola tricolor, sinapis alba, Lamium purpurea, Veronica persica Agrostis tenuis, Alopecurus myosuroides, Stellaria media to demonstrate the activity of the product against weeds in wheat and to demonstrate the selectivity of the 25 product in this crop.

0 General experimental procedure: The application is carried out post-emergence of the plant species.

16 A number of seeds determined according to the Splant species and the size of the seed are sown in 9 x 9 x 9 cm pots filled with light agricultural soil.

The seeds are then covered with a layer of soil of about 3 mm thickness and the seed is allowed to germinate until it produces a plantlet at a suitable stage. In the case of the grasses, the treatment stage is stage is the "formation of second leaf" stage. In the case of dicotyledons, the treatment stage is the "cotyledons unfolded, first true leaf being developed" stage.

The pots are then treated by spraying them with a mixture in an amount which corresponds to an application rate of 500 1/ha and which contains the active substances to be sprayed.

The mixtures are obtained by diluting the formulated products with water.

The following formulated products were used: aclonifen flowable having a content of 600 g/1, "Challenge 600"®, isoproturon flowable, with a content of 500 g/l, "Augur"', chlortoluron flowable, with a content of 500 g/l, "Dicuran"O, 25 dimefuron flowable, with a content of S 400 g/l, "Surdone", These formulations are duly approved and well known in the art.

I The pots are then placed in containers designed for receiving the watering water, in the form of subirrigation, and maintained for 24 days at ambient temperature and 60% relative humidity.

After 24 days, the number of live plants in the pots treated with the mixture containing the active substance to be tested is counted and so is the number of live plants in a control pot treated under the same conditions but using a mixture which does not contain active substance. In this way, the percentage destruction of the treated plants is determined in relation to the untreated control. A percentage destruction of 100% means that complete destruction of the plant species in 66 question has taken place, and a percentage of 0% means 15 that the number of live plants in the treated pot is identical to that in the control pot.

*6 O In the 'Dables in Exanples 1 to 16 the amounts of aclcznifen are given in the first column: the (mounts of substituted urea are given in the first row. Both a-*nts are in g.a.i./ha (gramms of active inrder/etr) 1 Example 1: 6.66 6e Trial showing the nature of the synercristic biolocical effect of the combination of isoproturon with aclonifen on Lolium ultiflorm.

The neriment is carried out having sown Lolium *6 multiflorum see, s.

o 6 The table below shows the average of a greenhouse trial. For each dosage rate, the higher value is the value obtained and the lower value is the expected value using Colby's formula.

Ve g o* S .9 *0 a Acl1 n i Len Isoproturon 0 500 1 000 2 000 0 0 3065 62 0 6090 65 125 0 65 90 65 250 0 65 90 98 65 With reference to the formula given at the beginning of the description, the results given in the table above clearly demonstrate the excellent and unexpected iegree of synergism obtained with the combination of the ivention.

ExamDle 2: Trial demonstrating the nature of the synercistic biolo~ica~l effect of the combination of isoproturon with aclonif en on Alopecurus myosuroides.

The experiment is carried out having sown Alopecurus myosuroides seeds.

The table below shows the average of a grecnhouse trial. F~or each dosage rate, the higher value is the value obtained and the lower value is the expected value using Colby's formula.

9e 9O a 0 a.

C

S OS 0* a 000 0 0* Sq 0

S

'S

a

S..

a

S

a a Aclonifen 19 Isoproturon 0 500 1 000 2 000 0 0 20 50 62 0 30 75 50 125 0 55 65 83 50 250 0 80 85 93 50 With reference to the formula given at the beginning of the description, the results given in the table above clearly demonstrate the excellent and unexpected degree of synergism obtained with the 5 combination of the invention.

Example 3: Trial demonstrating the nature of the synergistic biological effect of the combination of isoDroturon with aclonifen on Agrostis tenuis.

The experiment is carried out having sown Agrostis tenuis seeds.

The table below shows the average of a greenhouse trial. For each dosage rate, the higher value is the value obtained and the lower value is the expected value using Colby's formula.

Aclonifen Isoproturon 0 500 1 000 2 000 0 0 30 90 62 0 90 100 100 90 125 0 95 100 100 90 250 0 100 100 100 90 00 SO 0 le 0 0 0 0 d 0 .00

S

0006 0*0 0* *o 0S 0 0o 0 With reference to the formula given at the beginning of the description, the results given in the table above clearly demonstrate the excellent and unexpected degree of synergism obtained with the 5 combination of the invention.

Example 4: Trial demonstrating the nature of the synergistic biological effect of the combination of isDproturon with aclonifen on Lamium purnurea.

10 The experiment is carried out having sown Lamium purpurea seeds.

SI Se

S@

S S SO SC 0S C

S

Aclonifen 21 Isoproturon 0 500 1 000 2 000 0 0 0 15 62 0 20 20 0 15 125 20 40 30 30 36 250 20 55 50 32 36 With reference to the formula given at the beginning of the description, the results given in the table above clearly demonstrate the excellent and unexpected degree of synergism obtained with the combination of the invention.

Example Trial demonstrating the nature of the synergistic biological effect of the combination of isoproturon with aclonifen on Viola tricolor.

The experiment is carried out having sown Viola tricolor seeds.

RLF/0032P 22 Isoproturon Aclonifen .6 66 6n a c 6 6

S

S.

With reference to the formula given at the beginning of the description, the results given in the table above clearly demonstrate the excellent and unexpected degree of synergism obtained with the combination of the invention.

Example 6: Trial demonstrating the absence of phytotoxicity of the combination of isooroturon with aclonifen on wheat or Triticum aestivum.

The experimental procedure is as above, but after wheat seeds have been sown, and leads to the result given below: Isoproturon 0 500 1 000 2 000 0 0 0 0 0 I Aclonifen 62 0 0 0 0 125 0 0 0 0 250 0 0 0 0 23 It can therefore be said that the abovementioned combination, although increasing the particular activity of the two active substances against the weeds in the example, shows no phytotoxicity whatsoever to wheat.

Example 7: Trial demonstrating the nature of the synergistic biological effect of the combination of chlortoluron with aclonifen on Alopecurus myosuroides.

The experiment is carried out having sown Alopecurus myosuroides seeds.

The table below shows the average of a grsenhouse trial. For each dosage rate, the higher value is the value obtained and the lower value is the *4 15 expected value using Colby's formula.

Chlortoluron i Aclcnifen 500 1 000 1 500 70 60 97 97 70 85 99 68 73 82 98 jO 72 76 84 £450 a

S

Example 8: Trial demonstrating the nature of the synercistic biological effect of the combination of chlortoluron with aclonifen on Avena fatua.

The experiment is carried out having sown Avena fatua seeds.

Chlortoluron 0 500 1 000 1 500 0 0 0 10 55 93 Aclonifen 62 0 35 75 88 10 55 93 9.S S a 125 0 35 70 88 10 55 93 250 0 50 88 55 93 a 0 ee With reference to the formula given at the beginning of the description, the results given in the table above clearly demonstrate the excellent and unexpected degree of synergism obtained with the combination of the invention.

Example 9: Trial demonstrating the nature of the synergistic biological effect of the combination of chlortoluron with aclonifen on Lolium multiflorum.

The experiment is carried out having sown Lolium multiflorum seeds.

Chlortoluron 0 0 500 1 000 1 500 u° 0 0 78 93 00 *0 Aclonifen 62 0 100 100 S. 78 93 125 5 98 100 79 93 250 10 93 100 80 94 0 0* With reference tothe formula given at the beginning of the description, the results given in the table above clearly demonstrate the excellent and unexpected degree of synergism obtained with the combination of the invention.

Example Trial demonstrating the nature of the synergistic biological effect of the combination of chlortoluron with aclcnifen on Viola tricolor.

The experiment is carried out having sown Viola tricolor seeds.

Chlortoluron Aclonifen

S

*q 0 s 0 59 6*

S

0 500 1 000 1 500 0 0 0 15 62 0 20 35 0 15 125 0 30 60 0 15 250 5 35 70 19 29 0 With reference to the formula given at the beginning of the description, the results given in the table above clearly demonstrate the excellent and unexpected degree of synergism obtained with the combination of the invention.

Example 11: Trial demonstrating the nature of the synergistic biological effect of the combination of chlortoluron with aclonifen on Galium aparine.

The experiment is carried out having sown Gallum aparine seeds.

RLF/0032P 27 The table below shows the average of a greenhouse trial. For each dosage rate, the higher value is the value obtained and the lower value is the expected value using Colby's formula.

Chlortoluron 0 500 1 000 1 500 0 0 15 25 Aclonifen 62 0 30 40 25 125 0 45 70 25 250 15 60 70 28 36 53 *b S .8 5 With reference to the formula given at the 0 beginning of the description, the results given in the d a go table above clearly demonstrate the excellent and unexpected degree of synergism obtained with the combination of the invention.

10 Example 12: Trial demonstrating the absence of phytotoxicity of the combination of chlortoluron with aclonifen on wheat or Triticum aestivim.

99 The experimental procedure is as above, but after wheat seeds have been sown, and leads to the Chlortoluron result given below: Chlor 0 500 1 000 1 500 Aclonifen 0 0 0 0 0 0 0 0 0 0 It can therefore be said that the abovementioned combination, although increasing the particular activity of the two active substances against the weeds in the example, shows no phytotoxicity whatsoever to wheat.

Example 13: Trial demonstrating the nature of the synercistic biological effect of the combination of dimefuron with aclonifen on SinaDis alba.

The experiment is carried out having sown Sinapis alba seeds.

a The table below shows the average of a greenhouse trial. For each dosage rate, the higher c. value is the value obtaine., and the lower value is the 15 expected value using Colby's formula.

Dimefuron 0 500 1 000 2 000 S0 0 10 45 Aclonifen 62 0 35 93 100 45 125 20 80 98 100 28 56 76 250 30 70 100 100 S37 61 79 With reference to the formula given at the *beginning of the description, the results given in the table above clearly demonstrate the excellent and unexpected degree of synergism obtained with the combination of the invention.

Example 14: Trial demonstrating the nature of the synergistic biological effect of the combination of dimefuron with aclonifen on Viola tricolor.

The experiment is carried out having sown Viola tricolor seeds.

The table below shows the average of a 0 to greenhouse trial. For each dosage rate, the higher 00* 0. value is the value obtained and the lower value is the 15 expected value using Colby's formula.

Dimefuron 0 500 1 000 2 000 000* "0 Aclonifen 0 00 45 50 83 50 86 With reference to the formula given at the beginning of the description, the results given in the table above clearly demonstrate the excellent and unexpected degree of synergism obtained with the combination of the invention.

Example Trial demonstrating the nature of the synergistic biological effect of the combination of dimefuron with aclonifen on Lolium multiflorum.

The experiment is carried out having sown Lolium multiflorum seeds.

Dimefuron a S0 500 1 000 2 000 0 0 10 25 :4e Aclonifen 62 0 15 35 25 125 0 20 55 25 250 5 20 55 14 29 62 a With reference to the formula given at the eo beginning of the description, the results given in the table above clearly demonstrate the excellent and aunexpected degree of synergism obtained with the combination of the invention.

Example 16: Trial demonstratina the nature of ihp vnpraid-ic hiolnaira1 ieffe-1of the combination of dimefuron with aclonifen on Veronica persica.

The experiment is carried out having sown Veronica persica seeds.

Dimefuron Aclonifen 0 500 1 000 2 000 0 0 55 97 100 62 68 80 100 97 100 125 5 100 100 100 57 97 100 250 5 88 94 100 57 97 100 *9 CO p *0 p P0 S .C With reference to the formula given at the beginning of the description, the results given in the table above clearly demonstrate the excellent and unexpected degree of synergism obtained with the combination of the invention.

00 RLF/0032P Example 17: Trial demonstrating the nature of the synerqistic effect of the combination of aclonifen with methabenzthiazuron.

The trial is conducted in the field on 2 x 5 m plits in the form of bands and sown with two crops and a range of weeds in bands, with three replications per trial. Other weeds are present naturally.

The treatment is carried out when the crop and the weeds are at the stage where one sucker is developed completely, 'three suckers in the case of the monocotyledons and from the cotyledon stage to the plantlet stage in 15 the case of the diuotyledons.

The plots are treated with a test sprayer mounted on a tractor and with an output of 195 1/ha, using respectively aclonifen in the form of a suspension with a content of 600 g/1 (CHALLENGE 600), 20 methabenzthiazuron in liquid form with a content of x 700 g/1 (TRIBUNIL), in each case on their own and as a mixture.

After 60 days, the percentage of weeds present is scored visually by comparison with an untreated control (0 no effect, 100 complete destruction) on Galium aparine and Avena fatua, and on winter wheat and winter barley.

The table below shows the average of the 33 results from three replications per trial. The result is given for each dosage rate, observed by comparison with the result expected by applying Colby's formula.

Destruction in Galium aparine Destruction in Avena fatua C,

S

B.

C S Ce a a GC@ C Ce Ce

C

BC

CO

**W

S

055.56

B

OB*t C C S. 6 C. CS CI C

S

Active substance Found Expected Found Expected n gs. s. /ha 250 33 33 Aclonifen 500 45 iethabenzthiazuron 2000 6 72 hclonif en 250 37 93 81 ethab enz thiazuron 2000 clonifen 500 94 48 94 84 ethabenztlhiazuron 2000

C.

C. B Ce 4

S

This table clearly demonstrates the unexpected synergistic behaviour of the above combination.

Claims

1-methylurea, monolinuron, or 3- (4-chiorophenyl) -1-methoxy-

2.-methylurea, methabenzthiazuron, or 1-benzothiazol-2-yl- 1,3-dimethylurea, metobromuron, or 3-(4-bromophenyl)-l-methoxy- 1-methylurea, and dimefuron, or 3-[4-(5-tert-butyl-2 ,3-dihydro- 2-oxo-1, 3, 4-oxadiazol-3-yl) -3-chlorophenyl- 1, 1-dimethylurea.

3) The product according to claim 2, wherein the urea is 3-(4-isopropylphenyl) 1-dimethylurea (or isoproturon) or 3-(3-chloro-p-tolyl) -1,12-dimethylurea (or chiortoluron). 36

4. The product according to any one of claims 1 to 3, for simultaneous or separate use or use staggered over time, for treating undesirable plants or weeds in crops.

The product according to any one of claims 1 to 4, wherein the ratio by weight of aclonifen to substitute urea is between 6/400 and 2/1.

6. The product according to claim 5, wherein the ratio by weight of aclonifen to substituted urea is between 1/60 and 1.5/1 and preferably between 1/30 and 1/1.

7. The product according to any one of claims 1 to 4, which contains a dosage rate of aclonifen which is not, or is barely, herbicidal.

8. The product according to claim 7, wherein the ratio by weight of aclonifen to substituted urea is between 1/60 and 1/2.

9. A product according to claim 7 or claim 8 in which the aclonifen acts as an amplifier of the activity of the urea.

A herbicidal composition, containing a product according to one of claims 1 to 9, at least one inert carrier and/or at least one surfactant. 15

11. The herbicidal composition accorx.ng to claim 10, which contains between 0.5 and 95% of product according to one of claims 1 to 9.

12. A method of controlling weeds post-emergence of crops at a location, wlerein an effective dose of a product according to one of claims 1 to 9 is applied to the location. Oe* S *3 Mll e IO:\WPUSERIBFFIOOOBO:EA3R 30 of 3 37

13) The control method according to claim 12, -wherein the weeds controlled are: GaJlium aparine, Avena fatua,. Lolium multiflorun, Viola tricolor, Sinapis aJlba, Lamium purpurea, Veronica persica, Agrostis tenuis, Alopecurus ;xiyosuroides.

14) The control method according to claim 12, wherein the product is applied at a rate of 460 to 4200 g/ha.

The control method according to claim 12, wherein t-he combination of 3-(4-isopropyl-pheny-L)-,3.- dimethylurea or isoproturon, with aclonifen is applied a ata rate of: to 600 glha aclonifen and 400 to 3600 g/ha isoproturon, li as and wherein the crops are cereals.

16) The control method according to claim wherein 100 to 500 g/ha aclonifen and- P-0 500 to 3000 g/ha isoproturon are applied. 0

17) The control method according to claim 12, wherein the combination chiortoluron, or 3-(3-chloro-p- tolyl)-1,l-dimethy.urea, with aclonifen is applied at a a rate of: 60 to 600 g/ha aclonifen and 400 to 3600 g/ha chiortoluron, and wherein the crops are cereals.

18. The control method according to claim 17, wherein the combination is applied at a rate of: 100 to 500 g/ha aclonifen 'ad 500 to 3000 g/ha chlortoluron.

19. The control method according to claim 12, wherein the combination dimefuron, or N,N-dimethyl-N'-[3-chloro-4-(5-tert-butyl-2-oxo-2,3-dihydro-1,3,4-oxadiazolyl-3-yl)- phenyl]urea, with aclonifen is applied at a rate of: to 600 g/ha aclonifen and 400 to 3600 g/ha diraefuron, and wherein the crops are oilseed rape or peas.

The control method according to claim 19, wherein the combination is applied at a rate of: 100 to 500 g/ha aclonifen and 500 to 2000 g/ha dimefuron. 15

21. The control method according to claim 12, wherein the combination is applied at a .rate of: 60 to 1000 g/ha aclonifen and 500 to 4000 g/ha of methabenzthiazuron.

22. The control method according to claim 21, wherein the combination is applied at a S 20 rate of: 100 to 500 g/ha aclonifen and 1000 to 3000 g/ha methabenzthiazuron.

23. A herbicidal product which results from the synergic combination of aclonifen and one or more substituted urea, which product is substantially as herein described with reference to any one of the Examples.

24. A herbicidal composition comprising a product as defined in claim 23 together with a herbicidally acceptable carrier, adjuvant and/or diluent. A method of controlling weeds post-emergence of crops at a locus, which method comprises treating the locus with a product of claim 23 or a composition of claim 24 in an amount which effectively controls said weeds. Dated 6 August, 1993 Rhone-Poulenc Agrochimie Patent Attorneys for the Applicant/Nominated Person SPRUSON FERGUSON (G:\WPUSER\LIBFF10000:EAR 38 of 3