Note: Descriptions are shown in the official language in which they were submitted.
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Herbicidal composition
The present invention relates to a novel herbicidal synergistic composition
comprising a
herbicidal active ingredient combination that is suitable for the selective
control of weeds in crops
of useful plants, for example in crops of wheat and barley.
The compound pinoxaden exhibits herbicidal action, as described, for example,
in W099/47525.
The compound difenzoquat (difenzoquat metilsulfate) is likewise known as a
herbicide and
described in The Pesticide Manual, Twelfth Edition, BCPC, 2000, entry number
242.
Surprisingly, it has now been found that a combination of variable amounts of
the compound
pinoxaden with the compound difenzoquat exhibits a synergistic action that is
capable of
controlling the majority of weeds and grasses occurring especially in crops of
useful plants
without causing any appreciable damage to the useful plant.
There is therefore proposed in accordance with the present invention a novel
herbicidal
synergistic composition for selective weed control which, in addition to
comprising formulation
adjuvants, comprises as active ingredient a mixture of
a) the compound pinoxaden
and
b) a synergistically effective amount of the compound difenzoquat.
It is extremely surprising that the combination of the compound pinoxaden and
the compound
difenzoquat exceeds the additive action on the weeds and grasses to be
controlled that is to be
expected in principle and thus broadens the range of action of the two active
ingredients
especially in two respects: firstly, the rates of application of the
individual compounds are
reduced while a good level of action is maintained and, secondly, the
composition according to
the invention achieves a high level of weed control also in those cases where
the individual
substances, in the range of low rates of application, have become useless from
the agronomic
standpoint. The result is a considerable broadening of the spectrum of weeds
and an additional
increase in selectivity in respect of the crops of useful plants. In addition,
the composition
according to the invention, while retaining excellent control of weeds in
crops of useful plants,
also allows greater flexibility in succeeding crops.
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The mixing ratios in which the compound pinoxaden and the compound difenzoquat
may be
present in the composition according to the invention may vary within wide
limits. As a rule, the
compound pinoxaden and the compound difenzoquat are present in a ratio by
weight of from
1: 100 to 1000 : 1. Preferred mixing ratios of the compound pinoxaden and the
compound
difenzoquat are from 1: 50 to 1: 5.
The rate of application may also vary within wide limits and depends upon the
nature of the soil,
the method of application (pre- or post-emergence; seed dressing; application
to the seed furrow;
no tillage application etc.), the crop plant, the weed or grass to be
controlled, the prevailing
climatic conditions, and other factors governed by the method of application,
the time of
application and the target crop. The active ingredient mixture according to
the invention can
generally be applied at a rate of from 300 to 1200g/ha.
The herbicidal composition according to the present invention optionally
contains a safener,
preferably selected from cloquintocet-mexyl, cloquintocet acid and salts
thereof, fenchlorazole-
ethyl, fenchlorazole acid and salts thereof, mefenpyr-diethyl, mefenpyr
diacid, isoxadifen-ethyl,
isoxadifen acid, furilazole, furilazole R isomer, benoxacor, dichlormid, AD-
67, oxabetrinil,
cyometrinil, cyometrinil Z-isomer, fenclorim, cyprosulfamide, naphthalic
anhydride, flurazole, CL
304,415, dicyclonon, fluxofenim, DKA-24 and R-29148 PPG-1292.
More preferably, the safener is selected from cloquintocet-mexyl, cloquintocet
acid and salts
thereof, fenchlorazole-ethyl, fenchlorazole acid and salts thereof, mefenpyr-
diethyl, mefenpyr
diacid, isoxadifen-ethyl and isoxadifen acid.
The above-mentioned safeners are described, for example, in the Pesticide
Manual, Twelfth
Edition, British Crop Protection Council, 2000, or other readily available
resources. R-29148 is
described, for example by P.B. Goldsbrough et al., Plant Physiology, (2002),
Vol. 130 pp. 1497-
1505 and references therein and PPG-1 292 is known from W009211761.
The invention relates also to a method for the selective control of grasses
and weeds in crops of
useful plants, which comprises treating the useful plants or the area under
cultivation or the locus
thereof simultaneously or at different times with the compounds pinoxaden and
difenzoquat and
optionally with a safener.
Depending upon the intended use, the safener can be used for pretreating the
seed material of
the crop plant (dressing the seed or seedlings) or introduced into the soil
before or after sowing.
It can, however, also be applied alone or together with the herbicide before
or after emergence of
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the plants. The treatment of the plants or the seed material with the safener
can therefore take
place in principle independently of the time of application of the herbicide.
The treatment of the
plant by simultaneous application of herbicide and safener (e.g. in the form
of a tank mixture) is
generally preferred. The rate of application of safener relative to herbicide
is largely dependent
upon the mode of application. In the case of field treatment, generally from
0.001 to 5.0 kg of
safener/ha, preferably from 0.001 to 0.5 kg of safener/ha are used.
Crops of useful plants in which the composition according to the invention can
be used include
especially wheat and barley. The term "crops" is to be understood as also
including crops that
have been rendered tolerant to herbicides or classes of herbicides (for
example ALS, GS,
EPSPS, PPO and HPPD inhibitors) as a result of conventional methods of
breeding or genetic
engineering. An example of a crop that has been rendered tolerant e.g. to
imidazolinones, such
as imazamox, by conventional methods of breeding is Clearfield summer rape
(Canola).
Examples of crops that have been rendered tolerant to herbicides by genetic
engineering
methods include e.g. glyphosate- and glufosinate-resistant maize varieties
commercially
available under the trade names RoundupReady and LibertyLinkO
The weeds to be controlled may be both monocotyledonous and dicotyledonous
weeds, such as,
for example, Stellaria, Nasturtium, Agrostis, Digitaria, Avena, Setaria,
Sinapis, Lolium, Solanum,
Echinochloa, Scirpus, Monochoria, Sagittaria, Bromus, Alopecurus, Sorghum,
Rottboellia,
Cyperus, Abutilon, Sida, Xanthium, Amaranthus, Chenopodium, lpomoea,
Chrysanthemum,
Galium, Viola and Veronica.
Crops are also to be understood as being those which have been rendered
resistant to harmful
insects by genetic engineering methods, for example Bt maize (resistant to
European corn
borer), Bt cotton (resistant to cotton boll weevil) and also Bt potatoes
(resistant to Colorado
beetle). Examples of Bt maize are the Bt-176 maize hybrids of NK (Syngenta
Seeds). The Bt
toxin is a protein that is formed naturally by Bacillus thuringiensis soil
bacteria. Examples of
toxins and transgenic plants able to synthesise such toxins are described in
EP-A-451 878, EP-
A-374 753, WO 93/07278, WO 95/34656, WO 03/052073 and EP-A-427 529. Examples
of
transgenic plants that contain one or more genes which code for an
insecticidal resistance and
express one or more toxins are KnockOut (maize), Yield Gard (maize),
NuCOTIN33B
(cotton), Bollgard (cotton), NewLeaf@ (potatoes), NatureGard and Protexcta@.
Plant crops and
their seed material can be resistant to herbicides and at the same time also
to insect feeding
("stacked" transgenic events). Seed can, for example, have the ability to
express an insecticidally
active Cry3 protein and at the same time be glyphosate-tolerant. The term
"crops" is to be
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understood as aiso including crops obtained as a result of conventional
methods of breeding or
genetic engineering which contain so-called output traits (e.g. improved
flavour, storage stability,
nutritional content).
Areas under cultivation are to be understood as including land where the crop
plants are already
growing as well as land intended for the cultivation of those crop plants.
The composition according to the invention can be used in unmodified form. The
compositions
according to the invention are, however, generally formulated in a variety of
ways using
formulation adjuvants, such as carriers, solvents and surface-active
substances. The
formulations can be in various physical forms, for example in the form of
dusting powders, gels,
wettable powders, water-dispersible granules, water-dispersible tablets,
effervescent
compressed tablets, emulsifiable concentrates, microemulsifiable concentrates,
oil-in-water
emulsions, oil flowables, aqueous dispersions, oily dispersions,
suspoemulsions, capsule
suspensions, emulsifiable granules, soluble liquids, water-solubie
concentrates (with water or a
water-miscible organic solvent as carrier), impregnated polymer films or in
other forms known, for
example, from the Manual on Development and Use of FAO Specifications for
Plant Protection
Products, 5th Edition, 1999. Such formulations can either be used directly or
are diluted prior to
use. Diluted formulations can be prepared, for example, with water, liquid
fertilisers, micro-
nutrients, biological organisms, oil or solvents.
The formulations can be prepared, for example, by mixing the active ingredient
with formulation
adjuvants in order to obtain compositions in the form of finely divided
solids, granules, solutions,
dispersions or emulsions. The active ingredients can also be formulated with
other adjuvants, for
example finely divided solids, mineral oils, vegetable oils, modified
vegetable oils, organic
solvents, water, surface-active substances or combinations thereof. The active
ingredients can
also be contained in very fine microcapsules consisting of a polymer.
Microcapsules contain the
active ingredients in a porous carrier. This enables the active ingredients to
be released into their
surroundings in controlled amounts (e.g. slow release). Microcapsules usually
have a diameter of
from 0.1 to 500 microns. They contain active ingredients in an amount of about
from 25 to 95 %
by weight of the capsule weight. The active ingredients can be present in the
form of a monolithic
solid, in the form of fine particles in solid or liquid dispersion or in the
form of a suitable solution.
The encapsulating membranes comprise, for example, natural and synthetic gums,
cellulose,
styrene-butadiene copolymers, polyacrylonitrile, polyacrylate, polyester,
polyamides, polyureas,
polyurethane or chemically modified polymers and starch xanthates or other
polymers that are
known to the person skilled in the art in this connection. Alternatively it is
possible for very fine
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microcapsules to be formed wherein the active ingredient is present in the
form of finely divided
particles in a solid matrix of a base substance, but in that case the
microcapsule is not
encapsulated.
The formulation adjuvants suitable for the preparation of the compositions
according to the
invention are known per se. As liquid carriers there may be used: water,
toiuene, xylene,
petroleum ether, vegetable oils, acetone, methyl ethyl ketone, cyclohexanone,
acid anhydrides,
acetonitrile, acetophenone, amyl acetate, 2-butanone, butyine carbonate,
chlorobenzene, cyclo-
hexane, cyclohexanol, alkyl esters of acetic acid, diacetone alcohol, 1,2-
dichloropropane,
diethanolamine, p-diethylbenzene, diethylene glycol, diethylene glycol
abietate, diethylene glycol
butyl ether, diethylene glycol ethyl ether, diethylene glycol methyl ether,
N,N-dimethylformamide,
dimethyl sulfoxide, 1,4-dioxane, dipropylene glycol, dipropylene glycol methyl
ether, dipropylene
glycol dibenzoate, diproxitol, alkylpyrrolidone, ethyl acetate, 2-ethyl
hexanol, ethylene carbonate,
1,1,1-trichloroethane, 2-heptanone, alpha-pinene, d-limonene, ethyl
lactate,ethylene glycol,
ethylene glycol butyl ether, ethylene glycol methyl ether, gamma-
butyroiactone, glycerol, glycerol
acetate, glycerol diacetate, glycerol triacetate, hexadecane, hexylene glycol,
isoamyl acetate,
isobornyl acetate, isooctane, isophorone, isopropylbenzene, isopropyl
myristate, lactic acid,
laurylamine, mesityl oxide, methoxypropanol, methyl isoamyl ketone, methyl
isobutyl ketone,
methyl laurate, methyl octanoate, methyl oleate, methylene chloride, m-xyiene,
n-hexane, n-
octylamine, octadecanoic acid, octylamine acetate, oleic acid, oleylamine, o-
xylene, phenol,
polyethylene glycol (PEG 400), propionic acid, propyl lactate, propylene
carbonate,propylene
glycol, propylene glycol methyl ether, p-xylene, toluene, triethyl phosphate,
triethylene glycol,
xylenesulfonic acid, paraffin, mineral oil, trichloroethylene,
perchloroethylene, ethyl acetate, amyl
acetate, butyl acetate, propylene glycol methyl ether, diethylene glycol
methyl ether, methanol,
ethanol, isopropanol, and higher molecular weight alcohols, such as amyl
alcohol,
tetrahydrofurfuryl alcohol, hexanol, octanol, ethylene glycol, propylene
glycol, glycerol, N-methyl-
2-pyrrolidone and the like. Water is generally the carrier of choice for the
dilution of the
concentrates. Suitable solid carriers are, for example, talc, titanium
dioxide, pyrophyllite clay,
silica, attapulgite clay, kieseiguhr, limestone, calcium carbonate, bentonite,
calcium
montomorillonite, cottonseed husks, wheatmeal, soybean flour, pumice, wood
flour, ground
walnut shells, lignin and similar materials, as described, for example, in CFR
180.1001. (c) & (d).
A large number of surface-active substances can advantageously be used both in
solid and in
liquid formulations, especially in those formulations which can be diluted
with a carrier prior to
use. Surface-active substances may be anionic, cationic, non-ionic or
polymeric and they may be
used as emulsifiying, wetting or suspending agents or for other purposes.
Typical surface-active
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substances include, for example, salts of aikyl sulfates, such as
diethanolammonium lauryl
sulfate; salts of alkylaryisulfonates, such as calcium
dodecylbenzenesulfonate; alkylphenol-
alkylene oxide addition products, such as nonylphenol ethoxylate; alcohol-
alkylene oxide addition
products, such as tridecyl alcohol ethoxylate; soaps, such as sodium stearate;
salts of
alkylnaphthalenesulfonates, such as sodium dibutylnaphthalenesulfonate;
dialkyl esters of
sulfosuccinate salts, such as sodium di(2-ethylhexyl)sulfosuccinate; sorbitol
esters, such as
sorbitol oleate; quaternary amines, such as lauryl trimethylammonium chloride,
polyethylene
glycol esters of fatty acids, such as polyethylene glycol stearate; block
copolymers of ethylene
oxide and propylene oxide; and salts of mono- and di-alkyl phosphate esters;
and also further
substances described e.g. in "McCutcheon's Detergents and Emulsifiers Annual",
MC Publishing
Corp., Ridgewood, New Jersey, 1981.
Further adjuvants which can usually be used in pesticidal formulations include
crystallisation
inhibitors, viscosity-modifying substances, suspending agents, dyes, anti-
oxidants, foaming
agents, light absorbers, mixing aids, anti-foams, complexing agents,
neutralising or pH-modifying
substances and buffers, corrosion-inhibitors, fragrances, wetting agents,
absorption improvers,
micronutrients, plasticisers, glidants, lubricants, dispersants, thickeners,
anti-freezes,
microbiocides and also liquid and solid fertilisers.
The formulations may also comprise additional active substances, for example
further herbicides,
plant growth regulators, fungicides or insecticides.
The compositions according to the invention can additionally include an
additive comprising an
oil of vegetable or animal origin, a mineral oil, alkyl esters of such oils or
mixtures of such oils
and oil derivatives. The amount of oil additive used in the composition
according to the invention
is generally from 0.01 to 10 %, based on the spray mixture. For example, the
oil additive can be
added to the spray tank in the desired concentration after the spray mixture
has been prepared.
Preferred oil additives comprise mineral oils or an oil of vegetable origin,
for example rapeseed
oil, olive oil or sunflower oil, emulsified vegetable oil, such as
AMIGOO(Rhone-Poulenc Canada
Inc.), alkyl esters of oils of vegetable origin, for example the methyl
derivatives, or an oil of
animal origin, such as fish oil or beef tallow. A preferred additive contains,
for example, as active
components essentially 80 % by weight alkyl esters of fish oils and 15 % by
weight methylated
rapeseed oil, and also 5 % by weight of customary emulsifiers and pH
modifiers. Especially
preferred oil additives comprise alkyl esters of CB-C22 fatty acids,
especially the methyl
derivatives of C12-Ci$ fatty acids, for example the methyl esters of lauric
acid, paimitic acid and
oleic acid, being important. Those esters are known as methyl laurate (CAS-1
11-82-0), methyl
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palmitate (CAS-1 12-39-0) and methyl oleate (CAS-1 12-62-9). A preferred fatty
acid methyl ester
derivative is Emery 2230 and 2231 (Cognis GmbH). Those and other oil
derivatives are also
known from the Compendium of Herbicide Adjuvants, 5th Edition, Southern
Illinois University,
2000.
The application and action of the oil additives can be further improved by
combining them with
surface-active substances, such as non-ionic, anionic or cationic surfactants.
Examples of
suitable anionic, non-ionic and cationic surfactants are listed on pages 7 and
8 of WO 97/34485.
Preferred surface-active substances are anionic surfactants of the
dodecylbenzylsulfonate type,
especially the calcium salts thereof, and also non-ionic surfactants of the
fatty alcohol ethoxylate
type. Speciai preference is given to ethoxylated C12-C22 fatty alcohols having
a degree of
ethoxylation of from 5 to 40. Examples of commercially available surfactants
are the Genapol
types (Clariant AG). Also preferred are silicone surfactants, especially
polyalkyl-oxide-modified
heptamethyltrisiloxanes, which are commercially available e.g. as Silwet L-77
, and also
perfluorinated surfactants. The concentration of surface-active substances in
relation to the total
additive is generally from 1 to 30 % by weight. Examples of oil additives that
consist of mixtures
of oils or mineral oils or derivatives thereof with surfactants are Edenor ME
SU , Turbocharge
(Syngenta AG, CH) and Actipron (BP Oil UK Limited, GB).
The said surface-active substances may also be used in the formulations alone,
that is to say
without oil additives.
Furthermore, the addition of an organic solvent to the oil additive/surfactant
mixture can
contribute to a further enhancement of action. Suitable solvents are, for
example, Solvesso
(ESSO) and Aromatic Solvent (Exxon Corporation).The concentration of such
solvents can be
from 10 to 80 % by weight of the total weight. Such oil additives, which may
be in admixture with
solvents, are described, for example, in US-A-4 834 908. A commercially
available oil additive
disclosed therein is known by the name MERGE (BASF Corporation). A further
oil additive that
is preferred according to the invention is SCORE (Syngenta Crop Protection
Canada.)
In addition to the oil additives listed above, in order to enhance the
activity of the compositions
according to the invention it is also possibie for formulations of
alkylpyrrolidones, (e.g. Agrimax )
to be added to the spray mixture. Formulations of synthetic latices, such as,
for example,
polyacrylamide, polyvinyl compounds or poly-l-p-menthene (e.g. Bond , Courier
or Emerald )
can also be used. Solutions that contain propionic acid, for example Eurogkem
Pen-e-trate ,
can also be mixed into the spray mixture as activity-enhancing agents.
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The herbicidal formulations generally contain from 0.1 to 99 % by weight,
especially from 0.1 to
95 % by weight, of an active ingredient mixture of the compound pinoxaden and
the compound
difenzoquat and from 1 to 99.9 % by weight of a formulation adjuvant, which
preferably includes
from 0 to 25 % by weight of a surface-active substance. Whereas commercial
products will
preferably be formulated as concentrates, the end user will normally employ
dilute formulations.
Preferred formulations have especially the following compositions:
(% = percent by weight; "active ingredient mixture" denotes a mixture of the
compound
pinoxaden, the compound difenzoquat and, optionally, the safener):
Emulsifiable concentrates:
active ingredient mixture: 1 to 95 %, preferably 60 to 90 %
surface-active agent: 1 to 30 %, preferably 5 to 20 %
liquid carrier: I to 80 preferably 1 to 35 %
Dusts:
active ingredient mixture: 0.1 to 10 %, preferably 0.1 to 5 %
solid carrier: 99.9 to 90 %, preferabiy 99.9 to 99 %
Suspension concentrates:
active ingredient mixture: 5 to 75 %, preferably 10 to 50 %
water: 94 to 24 %, preferably 88 to 30 %
surface-active agent: I to 40 %, preferably 2 to 30 %
Wettable powders:
active ingredient mixture: 0.5 to 90 %, preferably 1 to 80 %
surface-active agent: 0.5 to 20 %, preferably 1 to 15 %
solid carrier: 5 to 95 %, preferably 15 to 90 %
Granules:
active ingredient mixture: 0.1 to 30 preferably 0.1 to 15 %
solid carrier: 99.5 to 70 %, preferably 97 to 85 %
The following Examples further illustrate, but do not limit, the invention.
Fl. Emulsifiable concentrates a) b) c) d)
active ingredient mixture 5 l0 10 % 25 l0 50 %
calcium dodecylbenzene-
sulfonate 6% 8% 6 Io 8%
castor oil polyglycol ether 4% - 4% 4%
(36 mol of ethylene oxide)
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octylphenol polyglycol ether - 4% - 2%
(7-8 mol of ethylene oxide)
NMP - - 10% 20%
arom. hydrocarbon 85 l0 78 l0 55 % 16 %
mixture C9-C12
Emulsions of any desired concentration can be prepared from such concentrates
by dilution with
water.
F2. Solutions a) b) c) d)
active ingredient mixture 5% 10 % 50 % 90 %
1-methoxy-3-(3-methoxy-
propoxy)-propane - 20 % 20 % -
polyethylene glycol MW 400 20 % 10 % - -
NMP - - 30% 10%
arom. hydrocarbon 75 to 60 % - -
mixture C9-C12
The solutions are suitable for application in the form of microdrops.
F3. Wettable powders a) b) c) d)
active ingredient mixture 5 % 25 % 50 % 80 %
sodium lignosulfonate 4 lo - 3 % -
sodium lauryl sulfate 2% 3 /o - 4%
sodium diisobutylnaphthafene-
sulfonate - 6 % 5 % 6 %
octylphenof polyglycol ether - 1 % 2% -
(7-8 mol of ethylene oxide)
highly disperse silicic acid 1 /o 3% 5% 10 to
kaolin 88 l0 62 % 35 % -
The active ingredient is thoroughly mixed with the adjuvants and the mixture
is thoroughly ground
in a suitable mill, yielding wettable powders which can be diluted with water
to give suspensions
of any desired concentration.
F4. Coated granules a) b) c)
active ingredient mixture 0.1 % 5 l0 15 to
highly disperse silicic acid 0.9 % 2% 2%
inorg. carrier 99.0 l0 93 % 83 %
(diameter 0.1 - 1 mm)
e.g. CaCO3 or Si02
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The active ingredient is dissolved in methylene chloride, the solution is
sprayed onto the carrier
and the solvent is subsequently evaporated off in vacuo.
F5. Coated qranules a) b) c)
active ingredient mixture 0.1 % 5% 15 lo
polyethylene glycol MW 200 1.0 % 2 l0 3%
highly disperse silicic acid 0.9 % 1 l0 2%
inorg. carrier 98.0 % 92 % 80 %
(diameter 0.1 - 1 mm)
e.g. CaCO3 or Si02
The finely ground active ingredient is applied uniformly, in a mixer, to the
carrier moistened with
polyethylene glycol. Non-dusty coated granules are obtained in this manner.
F6. Extruder granules a) b) C) d)
active ingredient mixture 0.1 % 3% 5% 15%
sodium lignosulfonate 1.5 % 2% 3 to 4%
carboxymethylcellu lose 1.4 % 2% 2% 2%
kaolin 97.0 l0 93 /o 90% 79%
The active ingredient is mixed and ground with the adjuvants and the mixture
is moistened with
water. The resulting mixture is extruded and then dried in a stream of air.
F7. Dusts a) b) C)
active ingredient mixture 0.1 % 1 % 5%
talcum 39.9 % 49 % 35 %
kaolin 60.0 l0 50 % 60 %
Ready-to-use dusts are obtained by mixing the active ingredient with the
carriers and grinding the
mixture in a suitable mill.
F8. Suspension concentrates a) b) c) d)
active ingredient mixture 3% 10 % 25 l0 50 %
ethylene glycol 5% 5 l0 5 l0 5 lo
nonylphenol polyglycol ether - 1% 2% -
(15 mol of ethylene oxide)
sodium lignosulfonate 3% 3% 4% 5 %
carboxymethylcellulose 1 % 1 % 1 % 1 lo
37 % aqueous formaldehyde 0.2 % 0.2 % 0.2 % 0.2 %
solution
silicone oil emulsion 0.8 % 0.8 % 0.8 % 0.8 %
water 87% 79% 62% 38%
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The finely ground active ingredient is intimately mixed with the adjuvants,
yielding a suspension
concentrate from which suspensions of any desired concentration can be
prepared by dilution
with water.
It is often more practical for the compound pinoxaden and the mixing partner
difenzoquat to be
formulated separately and then to be combined in the applicator in the desired
mixing ratio in the
form of a "tank mixture" in water shortly before application.
Biological Examples
A synergistic effect exists whenever the action of, for example, the active
ingredient combination
of pinoxaden and difenzoquat is greater than the sum of the actions of the
active ingredients
applied separately. The herbicidal action to be expected for a given
combination of two
herbicides can be calculated in accordance with the method of COLBY, S.R.
"Calculating
synergistic and antagonistic response of herbicide combinations". Weeds 15,
pages 20-22, 1967.
The synergistic effect of the combinations of the compound pinoxaden with the
compound
difenzoquat is demonstrated in the following Examples.
Example B1: Post-emergence test:
The test plants are raised to a post-application stage in seed trays under
greenhouse conditions.
A standard soil is used as cultivation substrate. At a post-emergence stage,
the herbicides, both
alone and in admixture, are applied to the test plants: pinoxaden in form of
Axiale100EC and
difenzoquat in form of Avenge 2SL150. The rates of application are governed by
the optimum
concentrations determined under field or greenhouse conditions. The tests are
evaluated 15
days later (100 % = plant is completely dead; 0 % = no phytotoxic action on
the plant).
Compound Rate (g/ha) Wheat Barley LOLMU LOLMU
expected observed
Pinoxaden 30 0 0 48
45 0 0 68
Difenzoquat 750 1 1 5
Pinoxaden + 30 + 750 0 2 53 85
Difenzoquat 45 + 750 3 7 73 95
LOLMU = lolium multiflorum
Similar results can be obtained when the compounds pinoxaden and difenzoquat
are formulated
in accordance with other Examples of WO 97/34485.
