Title of Invention

A METHOD OF CONTROLLING THE AQUATIC WEED HYDRILLA VERTICILLATA

Abstract A method of controlling the aquatic weed Hydrilla verticillata which comprises allowing a herbicidally effective amount of (RS)-2-(4-isopropyl-4-methyl-5-oxo-2-imidazolin-2-yl)-5-methoxymethylnicotinic acid (imazamox) or an agriculturally acceptable salt thereof to act on the aquatic weed and/or its aqueous habitat containing seeds or other propagating organs of said aquatic weed.
Full Text A method of controlling the aquatic weed Hydrilla verticillata
The present invention relates to a method of corrtrolling the aquatic weed Hydrilla
verticillata.
Aquatic weeds often have detrimental effects on the environment or the economics of
waters and wetlands, for example in the United States of America, in particular in wet
areas such as parts of Florida.
The kinds of aquatic weeds and herbicidal or biological methods for fighting aquatic
weeds are known, for example from L.W.J. Anderson, Pest Manag. Sci. 59, pages 801-
813 (online 2003) or M.D. Netherland et al., Outlooks on Pest Management (Pesticide
Outrlook), pages 100-104 or J. Gallagher and W.T. Haller, 1990, Rev. Weed Sci., 5,
pages 115-192.
In general terms US 5,334,576 (col. 18) discloses that certain imidazolinone herbicides
are useful as aquatic herbicides. Also in general terms US 4,798,619 discloses that
certain imidazolinone herbicides are useful as aquatic herbicides (col. 55) and does
exemplify (Example 101) the treatment of Eichhornia crassipes (water hyacinth) with
e.g. imazapyr or its Calcium salt.
One of the most noxious aquatic weeds is Hydrilla verticillata. Hydrilla verticillata is a
submersed, very prolific, mat forming species, which can dominate the aquatic system,
e.g. ponds, lakes, creeks, rivers, that it is present in. High densities of Hydrilla
verticillata interfere with various water uses.
In a preliminary research report it was stated that imazapyr may be effective in
reducing maturation of tubers or preventing successful development of new plants from
them (L.W.J. Anderson, Res. Prog. Rep. West. Soc. Weed Sci. 1986 Meet., page 304).
One of the major herbicides used for the control of Hydrilla verticillata has been
fluridone. There are now new biotypes of Hydrilla verticillata with an increased
tolerance or even resistance to fluridone.
Thus the need for a herbicidal compound for fighting Hydrilla verticillata, in particular for
fighting Hydrilla verticillata which is tolerant or resistant to fluridone herbicide is
warranted.
Surprisingly, it has now been found that imazamox or agriculturally acceptable salts
thereof, optionally in combination with at least one other herbicide B effectively
provides growth suppression or control of Hydrilla verticillata.

Imazamox (including its optical isomers) is a known herbicide which is described for
example in US 5,334,576. The R-lsomer of imazamox is known from e.g. US 5,973,154
or US 6,339,158 B1.
The present invention therefore relates to a method of controlling the aquatic weed
Hydrilla verticillata which comprises allowing a herbicidally effective amount of (RS)-2-
(4-isopropyl-4-methyi-5-oxo-2-imidazolin-2-yl)-5-methoxymethylnicotinic acid
(imazamox) or an agriculturally acceptable salt thereof to act on the aquatic weed
and/or its aqueous habitat containing seeds or other propagating organs (i.e. tubers,
turions) of said aquatic weed.
Habitat means the living space of the plants, e.g. ponds, lakes, rivers, creeks, swamps,
canals, reservoirs, and ditches.
A particularly preferred embodiment of the invention comprises the use of imazamox
for fighting Hydrilla verticillata wherein the aquatic weed Hydrilla verticillata is resistant
to the herbicide fluoridone.
Another particularly preferred embodiment of the invention comprises the use of one of
the optical isomers (the R-enatiomer or S-enantiomer) of imazamox, very preferably
the R-enantiomer of imazamox.
Another particularly preferred embodiment of the invention comprises method of
controlling the aquatic weed Hydrilia verticillata which comprises allowing a herbicidally
effective amount of imazamox or an agriculturally acceptable salt thereof to act on the
aquatic weed and/or its aqueous habitat containing seeds or other propagating organs
of said aquatic weed in the presence of rice plants.
Imazamox can be used in combination with one or more other herbicide(s) or an
agriculturally acceptable salt or derivative thereof. Examples of such other herbicide(s)
are the herbicides B selected from the following classes b1) to b15):
b1) lipid biosynthesis inhibitors;
b2) acetolactate synthase inhibitors (ALS inhibitors);
b3) photosynthesis inhibitors;
b4) protoporphyrinogen-IX oxidase inhibitors;
b5) bleacher herbicides;
b6) enolpyruvyl shikimate 3-phosphate synthase inhibitors (EPSP inhibitors);
b7) glutamine synthetase inhibitors;
b8) 7,8-dihydropteroate synthase inhibitors (DHP inhibitors);
b9) mitose inhibitors;
b10) inhibitors of the synthesis of long chain fatty acids (VLCFA inhibitors);

b11) cellulose biosynthesis inhibitors;
b12) decoupler herbicides;
b13) auxin herbicides;
b14) auxin transport inhibitors;
b15) other herbicides selected from the group consisting of benzoylprop, flamprop,
flamprop-M, bromobutide, chlorflurenol, cinmethylin, methyldymuron,
etobenzanid, fosamine, metam, pyributicarb, oxaziclomefone, dazomet, triaziflam
and methyl bromide;
all including the agriculturally acceptable salts and the agriculturally acceptable
derivatives thereof, provided they have a carboxyl group.
Preferred herbicides of groups b1) to b15) are the compounds listed below:
b1) from the group of the lipid biosynthesis inhibitors:
chlorazifop, clodinafop, clofop, cyhalofop, diclofop, fenoxaprop, fenoxaprop-p,
fenthiaprop, fluazifop, fluazifop-P, haloxyfop, haloxyfop-P, isoxapyrifop,
metamifop, propaquizafop, quizalofop, quizalofop-P, trifop, alloxydim,
butroxydim, clethodim, cloproxydim, cycloxydim, profoxydim, sethoxydim,
tepraloxydim, tralkoxydim, butylate, cycloate, diallate, dimepiperate, EPTC,
esprocarb, ethiolate, isopolinate, methiobencarb, molinate, orbencarb, pebulate,
prosulfocarb, sulfallate, thiobencarb, tiocarbazil, triallate, vernolate, benfuresate,
ethofumesate, bensulide and pinoxaden;
b2) from the group of the ALS inhibitors:
amidosulfuron, azimsulfuron, bensulfuron, chlorimuron, chlorsulfuron,
cinosulfuron, cyclosulfamuron, ethametsulfuron, ethoxysulfuron, flazasulfuron,
flupyrsulfuron, foramsulfuron, halosulfuron, imazosulfuron, iodosulfuron,
mesosulfuron, metsulfuron, nicosulfuron, oxasulfuron, primisulfuron, prosulfuron,
pyrazosulfuron, rimsulfuron, sulfometuron, sulfosulfuron, thifensulfuron,
triasulfuron, tribenuron, trifloxysulfuron, triflusulfuron, tritosulfuron,
imazamethabenz, imazapic, imazapyr, imazaquin, imazethapyr, cloransulam,
diclosulam, florasulam, flumetsulam, metosulam, penoxsulam, bispyribac,
pyriminobac, propoxycarbazone, flucarbazone, pyribenzoxim, pyriftalid,
pyrithiobac, flucetosulfuron, orthosulfamuron, pyrimisulfan;
b3) from the group of the photosynthesis inhibitors:
atraton, atrazine, ametryne, aziprotryne, cyanazine, cyanatryn, chlorazine,
cyprazine, desmetryne, dimethametryne, dipropetryn, eglinazine, ipazine,
mesoprazine, methometon, methoprotryne, procyazine, proglinazine, prometon,
prometryne, propazine, sebuthylazine, secbumeton, simazine, simeton,
simetryne, terbumeton, terbuthylazine, terbutryne, trietazine, ametridione,

amibuzin, hexazinone, isomethiozin, metamitron, metribuzin, bromacil, isocil,
lenacil, terbacil, brompyrazon, chloridazon, dimidazon, desmedipham,
phenisopham, phenmedipham, phenmedipham-ethyl, benzthiazuron, buthiuron,
ethidimuron, isouron, methabenzthiazuron, monoisouron, tebuthiuron,
thiazafluron, anisuron, buturon, chlorbromuron, chloreturon, chlorotoluron,
chloroxuron, difenoxuron, dimefuron, diuron, fenuron, fluometuron, fluothiuron,
isoproturon, linuron, methiuron, metobenzuron, metobromuron, metoxuron,
monolinuron, monuron, neburon, parafluron, phenobenzuron, siduron,
tetrafluron, thidiazuron, cyperquat, diethamquat, difenzoquat, diquat,
morfamquat, paraquat, bromobonil, bromoxynil, chloroxynil, iodobonil, ioxynil,
amicarbazone, bromofenoxim, flumezin, methazole, bentazone, propanil,
pentanochlor, pyridate, and pyridafol;
b4) from the group of the protoporphyrinogen-IX oxidase inhibitors: acifluorfen,
bifenox, chlomethoxyfen, chlornitrofen, ethoxyfen, fluorodifen, fluoroglycofen,
fluoronitrofen, fomesafen, furyloxyfen, halosafen, lactofen, nitrofen, nitrofluorfen,
oxyfluorfen, fluazolate, pyraflufen, cinidon-ethyl, flumiclorac, flumioxazin,
flumipropyn, fluthiacet, thidiazimin, oxadiazon, oxadiargyl, azafenidin,
carfentrazone, sulfentrazone, pentoxazone, benzfendizone, butafenacil,
pyraclonil, profluazol, flufenpyr, flupropacil, nipyraclofen, etnipromid, and
bencarbazone;
b5) from the group of the bleacher herbicides: metflurazon, norflurazon, flufenican,
diflufenican, picolinafen, beflubutamid, fluridone, flurochloridone, flurtamone,
mesotrione, sulcotrione, isoxachlortole, isoxaflutole, benzofenap, pyrazolynate,
pyrazoxyfen, benzobicyclon, amitrole, clomazone, aclonifen, 4-(3-trifluoromethyl-
phenoxy)-2-(4-trifluoromethylphenyl)pyrimidine, known from EP 723960,
topramezone, 4-hydroxy-3-{[2-methyl-6-(trifluoromethyl)-3-
pyridinyl]carbonyI}bicyclo[3.2.1]oct-3-en-2-one, known from WO 00/15615, 4-
hydroxy-3-{[2-(2-methoxyethoxy)methyl-6-(trifluoro-methyl)-3-
pyridinyl]carbonyi}bicylo[3.2.1]oct-3-en-2-one, known from WO 01/94339, 4-
hydroxy-3-[4-(methylsulfonyl)-2-nitrobenzoyl]bicyciot3.2.1]-oct-3-en-2-one,
known from EP 338992, 2-[2-chloro-4-(methylsulfonyl)-3-[(2,2,2-
trifluoroethoxy)methyl]benzoyl]-3-hydroxy-2-cyclohexen-1-one (known from DE
19846792), and pyrasulfotole;
b6) from the group of the EPSP synthase inhibitors: glyphosate;
b7) from the group of the glutamine synthase inhibitors: glufosinate and bilanaphos;
b8) from the group of the DHP synthase inhibitors: asulam;

b9) from the group of the mitose inhibitors:
benfluralin, butralin, dinitramine, ethalfluraiin, fluchloralin, isopropalin,
methaipropalin, nitralin, oryzalin, pendimethalin, prodiamine, profluralin, trifluralin,
amiprofos-methyl, butamifos, dithiopyr, thiazopyr, propyzamide, tebutam,
chlorthal, carbetamide, chlorbufam, chlorpropham and propham;
b10) from the group of the VLCFA inhibitors: acetochlor, alachlor, butachlor,
butenachlor, delachlor, diethatyl, dimethachlor, dimethenamid, dimethenamid-P,
metazachlor, metolachlor, S-metolachlor, pretilachlor, propachlor, propisochlor,
prynachlor, terbuchlor, thenylchlor, xylachior, allidochlor, CDEA, epronaz,
diphenamid, napropamide, naproanilide, pethoxamid, flufenacet, mefenacet,
fentrazamide, anilofos, piperophos, cafenstrole, indanofan and tridiphane;
b11) from the group of the cellulose biosynthesis inhibitors: dichlobenil, chlorthiamid,
isoxaben and flupoxam;
b12) from the group of the decoupler herbicides: dinofenate, dinoprop, dinosam,
dinoseb, dinoterb, DNOC, etinofen and medinoterb;
b13) from the group of the auxin herbicides:
clomeprop, 2,4-D, 2,4,5-T, MCPA, MCPA thioethyl, dichlorprop, dichlorprop-P,
mecoprop, mecoprop-P, 2,4-DB, MCPB, chloramben, dicamba, 2,3,6-TBA,
tricamba, quinclorac, quinmerac, clopyralid, fluroxypyr, picloram, triclopyr,
benazolin and aminopyralid;
b14) from the group of the auxin transport inhibitors: naptalam, diflufenzopyr;
b15) benzoylprop, flamprop, flamprop-M, bromobutide, chlorflurenol, cinmethylin,
methyldymron, etobenzanid, fosamine, metam, pyributicarb, oxaziclomefone,
dazomet, triaziflam, methyl bromide;
all including the agriculturally acceptable salts and the agriculturally acceptable
derivatives of the respective herbicides, provided they have a carboxyl group.
The herbicides B of groups b1) to b15) are known herbicides, see the quoted literature
references and, for example, The Compendium of Pesticide Common Names
(http://www.hclrss.demon.co.uk/index.html); Farm Chemicals Handbook 2000 Vol. 86,
Meister Publishing Company, 2000; B. Hock, C. Fedtke, R. R. Schmidt, Herbizide,
Georg Thieme Verlag, Stuttgart 1995; W. H. Ahrens, Herbicide Handbook, 7th Edition,
Weed Science Society of America, 1994; and K. K. Hatzios, Herbicide Handbook,
Supplement to 7th Edition, Weed Science Society of America, 1998.

The categorization of the active compounds according to their mode of action is based
on current understanding. If an active compound acts by more than one mode of
action, this substance was assigned to only one mode of action.
If imazamox, or the herbicides B are capable of forming geometrical isomers, for
example E/Z isomers, it is possible to use both the pure isomers and mixtures thereof
in the compositions according to the invention.
If the herbicides B have one or more centers of chirality and, as a consequence, are
present as enantiomers or diastereomers, it is possible to use both the pure
enantiomers and diastereomers and their mixtures in the compositions according to the
invention.
Imazamox does and the herbicides B may have functional groups which can be
ionized, thus imazamox and the herbicides B can also be used in the form of their
agriculturally acceptable salts. In general, the salts of those cations or the acid addition
salts of those acids are suitable whose cations and anions, respectively, have no
adverse effect on the action of the active compounds.
Preferred cations are the ions of the alkali metals, preferably of lithium, sodium and
potassium, of the alkaline earth metals, preferably of calcium and magnesium, and of
the transition metals, preferably of manganese, copper, zinc and iron, furthermore
ammonium and substituted ammonium in which one to four hydrogen atoms are
replaced by C1-C4-alkyl, hydroxy-C1-C4-alkyl, C1-C4-alkoxy-C1-C4-alkyl, hydroxy-C1-C4-
alkoxy-C1-C4-a!kyl, phenyl or benzyl, preferably ammonium, methylammonium,
isopropylammonium, dimethylammonium, diisopropylammonium, trimethylammonium,
tetramethylammonium, tetraethylammonium, tetrabutylammonium, 2-
hydroxyethylammonium, 2-(2-hydroxyethoxy)eth-1-ylammonium, di(2-hydroxyeth-1-
yl)ammonium, benzyltrimethylammonium, benzyltriethylarnmonium, furthermore
phosphonium ions, sulfonium ions, preferably tri(C1-C4-alkyl)sulfonium such as
trimethylsuifonium, and sulfoxonium ions, preferably tri(C1-C4-alkyl)sulfoxonium.
Anions of useful acid addition salts are primarily chloride, bromide, fluoride, iodide,
hydrogen sulfate, methyl sulfate, sulfate, dihydrogen phosphate, hydrogen phosphate,
nitrate, dicarbonate, carbonate, hexafluorosilicate, hexafluorophosphate, benzoate and
the anions of C1-C4-alkanoic acids, preferably formate, acetate, propionate and
butyrate.
According to the invention, the active compounds which carry a carboxyl group can,
instead of the active compounds mentioned above, also be employed in the form of an
agriculturally acceptable derivative, for example as amides such as mono- or di-C1-C6-
alkylamides or arylamides, as esters, for example as allyl esters, propargyl esters, C1-

C-10-alkyl esters or alkoxyalkyl esters, and also as thioesters, for example as C1-C10-
alkyl thioesters.
Preferred mono- and di-C1-C6-alkylamides are the methyl- and the dimethylamides.
Preferred arylamides are, for example, the anilidines and the 2-chloroanilides.
Preferred alkyl esters are, for example, the methyl, ethyl, propyl, isopropyl, butyl,
isobutyl, pentyl, mexyl (1-methylhexyl) or isooctyl (2-ethylhexyl) esters. Preferred C1-
C4-alkoxy-C1-C4-alkyl esters are the straight-chain or branched C1-C4-alkoxyethyl
esters, for example the methoxyethyl, ethoxyethyl or butoxyethyl esters. An example of
the straight-chain or branched C1-C10-alkyl thioesters is the ethyl thioester.
In binary compositions which comprise imazamox and at least one herbicide B, the
weight ratio of the active compounds imazamox:B is usually in the range from 1:500 to
10:1, preferably in the range from 1:100 to 10:1, in particular in the range from 1:50 to
10:1 and particularly preferably in the range from 1:25 to 5:1.
Regarding combinations of imazamox and herbicides B, preference is given to those
compositions of the invention which comprise imazamox in combination with at least
one and preferably exactly one herbicidally active compound selected from the group
consisting of b2) ALS inhibitors, preferably imazapyr; b5) bleacher herbicides,
preferably fluridone; b 13) auxin herbicides, preferably quinclorac; b14) auxin transport
inhibitors, preferably diflufenzopyr; and endothall.
For application ready-to-use preparations in the form of crop protection products can
be employed. Imazamox and optionally component B may be present in suspended,
emulsified or dissolved form and can be formulated jointly or separately. The
application forms depend entirely on the intended use.
The preparations can be applied, for example, in the form of directly sprayable
aqueous solutions, powders, suspensions, also highly-concentrated aqueous, oily or
other suspensions or dispersions, emulsions, oil dispersions, pastes, dusts, materials
for spreading or granules, by means of spraying, atomizing, dusting, broadcasting or
watering. The use forms depend on the intended use; in any case, they should ensure
the finest possible distribution of the active compounds.
Depending on the form in which the ready-to-use preparations are present, they
comprise one or more liquid or solid carriers, if appropriate surfactants and if
appropriate further auxiliaries which are customary for formulating crop protection
products. The person skilled in the art is sufficiently familiar with the recipes for such
formulations.

The ready-to-use preparations may comprise auxiliaries, which are customary for
formulating crop protection products, which auxiliaries may also comprise a liquid
carrier.
Suitable inert additives with carrier function are essentially: mineral oil fractions of
medium to high boiling point, such as kerosene and diesel oil, furthermore coal tar oils
and oils of vegetable or animal origin, aliphatic, cyclic and aromatic hydrocarbons, e.g.
paraffins, tetrahydronaphthalene, alkylated naphthalenes and their derivatives,
alkylated benzenes and their derivatives, alcohols such as methanol, ethanol,
propanol, butanol and cyclohexanol, ketones such as cyclohexanone, strongly polar
solvents, e.g. amines such as N-methylpyrrolidone, and water.
Aqueous use forms can be prepared from emulsion concentrates, suspensions, pastes,
wettable powders or water-dispersible granules by adding water. To prepare
emulsions, pastes or oil dispersions, the active compound (s) as such or dissolved in
an oil or solvent, can be homogenized in water by means of wetting agent, tackifier,
dispersant or emulsifier. Alternatively, it is possible to prepare concentrates consisting
of active substance, wetting agent, tackifier, dispersant or emulsifier and, if desired,
solvent or oil, and these concentrates are suitable for dilution with water.
Suitable surfactants are the alkali metal salts, alkaline earth metal salts and ammonium
salts of aromatic sulfonic acids, e.g. ligno-, phenol-, naphthalene- and
dibutylnaphthalenesulfonic acid, and of fatty acids, of alky]- and alkylarylsulfonates, of
alkyl sulfates, lauryl ether sulfates and fatty alcohol sulfates, and salts of sulfated hexa,
hepta- and octadecanols and of fatty alcohol glycol ethers, condensates of sulfonated
naphthalene and its derivatives with formaldehyde, condensates of naphthalene or of
the naphthalenesulfonic acids with phenol and formaldehyde, polyoxyethylene
octylphenol ether, ethoxylated isooctyl-, octyl- or nonylphenol, alkylphenyl polyglycol
ethers, tributylphenyl polyglycol ether, alkylaryl polyether alcohols, isotridecyl alcohol,
fatty alcohol/ethylene oxide condensates, ethoxylated castor oil, polyoxyethylene alkyl
ether or polyoxypropylene alkyl ether, lauryl alcohol polyglycol ether acetate, sorbitol
esters, lignosulfite waste liquors or methylcellulose.
Powders, materials for spreading and dusts can be prepared by mixing or concomitant
grinding of the active substances with a solid carrier.
Granules, e.g. coated granules, impregnated granules and homogeneous granules,
can be prepared by binding the active ingredient (s) to solid carriers. Solid carriers are
mineral earths such as silicas, silica gels, silicates, talc, kaolin, limestone, lime, chalk,
bole, loess, clay, dolomite, diatomaceous earth, calcium sulfate, magnesium sulfate,
magnesium oxide, ground synthetic materials, fertilizers such as ammonium sulfate,
ammonium phosphate, ammonium nitrate, ureas, and products of vegetable origin

such as cereal meal, tree bark meal, wood meal and nutshell meal, cellulose powders,
or other solid carriers.
The concentrations of the active compound (s) in the ready-to-use preparations can be
varied within wide ranges. In general, the formulations comprise from 0.001 to 98% by
weight, preferably 0.01 to 95% by weight, of active ingredient (s). The active ingredient
(s) are employed in a purity of from 90% to 100%, preferably 95% to 100% (according
to NMR spectrum).
The preparations can, for example, be formulated as follows:
I 20 parts by weight of the active compound (s) in question are dissolved in a
composition composed of 80 parts by weight of alkylated benzene, 10 parts by
weight of the adduct of 8 to 10 mol of ethylene oxide to 1 mol of oleic acid N-
monoethanolamide, 5 parts by weight of calcium dodecylbenzenesulfonate and 5
parts by weight of the adduct of 40 mol of ethylene oxide to 1 mol of castor oil.
Pouring the solution into 100 000 parts by weight of water and finely distributing it
therein gives an aqueous dispersion which comprises 0.02% by weight of the
active ingredient.
II 20 parts by weight of the active compound (s) in question are dissolved in a
composition composed of 40 parts by weight of cyclohexanone, 30 parts by
weight of isobutanol, 20 parts by weight of the adduct of 7 mol of ethylene oxide
to 1 mol of isooctylphenol and 10 parts by weight of the adduct of 40 mol of
ethyiene oxide to 1 moi of castor oil. Pouring the solution into 100 000 parts by
weight of water and finely distributing it therein gives an aqueous dispersion
which comprises 0.02% by weight of the active ingredient.
III 20 parts by weight of the active compound (s) in question are dissolved in a
composition composed of 25 parts by weight of cyclohexanone, 65 parts by
weight of a mineral oil fraction of boiling point 210 to 280°C and 10 parts by
weight of the adduct of 40 mol of ethylene oxide to 1 mol of castor oil. Pouring the
solution into 100 000 parts by weight of water and finely distributing it therein
gives an aqueous dispersion which comprises 0.02% by weight of the active
ingredient.
IV 20 parts by weight of the active compound (s) in question are mixed thoroughly
with 3 parts by weight of sodium diisobutylnaphthalenesulfonate, 17 parts by
weight of the sodium salt of a lignosulfonic acid from a sulfite waste liquor and 60
parts by weight of pulverulent silica gel, and the composition is ground in a
hammer mill. Finely distributing the composition in 20 000 parts by weight of

water gives a spray composition which comprises 0.1% by weight of the active
ingredient.
V 3 parts by weight of the active compound (s) in question are mixed with 97 parts
by weight of finely divided kaolin. This gives a dust which comprises 3% by
weight of the active ingredient.
VI 20 parts by weight of the active compound (s) in question are mixed intimately
with 2 parts by weight of calcium dodecylbenzenesulfonate, 8 parts by weight of
fatty alcohol polyglycol ether, 2 parts by weight of the sodium salt of a phenol-
urea-formaldehyde condensate and 68 parts by weight of a paraffinic mineral oil.
This gives a stable oily dispersion.
VII 1 part by weight of the active compound (s) in question is dissolved in a
composition composed of 70 parts by weight of cyclohexanone, 20 parts by
weight of ethoxylated isooctylphenol and 10 parts by weight of ethoxylated castor
oil. This gives a stable emulsion concentrate.
VIII 1 part by weight of the active compound (s) in question is dissolved in a
composition composed of 80 parts by weight of cyclohexanone and 20 parts by
weight of Wettol EM 31 (nonionic emulsifier based on ethoxylated castor oil). This
gives a stable emulsion concentrate.
The components imazamox and/or B can be formulated jointly or separately.
The components imazamox and as the case may be B can be applied jointly or
separately, simultaneously or successively, before, during or after emergence of the
plants.
The required application rate of the pure active compound(s) imazamox, optionally in
combination with B without formulation auxiliary, depends on the density of the
undesired vegetation, on the development stage of the plants, on the climatic
conditions of the location where the composition is used and on the application
method. In general, the application rate is from 1 to 1000 ppb (parts per billion),
preferably from 10 to 500 ppb and in particular from 25 to 300 ppb of active substance.
The preparations are applied to the water body as either a surface or subsurface
application. Application can be carried out by customary spraying techniques using, for
example, water as carrier and spray liquid rates of from about 50 to 1 000 I/ha (for
example from 300 to 400 I/ha). Application of the preparations by the low-volume and
the ultra-low-volume method is possible, as is their application in the form of
microgranules.

transferred into the water column. Hydrilla plants were selected for uniformity and
length of shoot growth (approx 15 cm). Plants were allowed to equilibrate in the
columns for 24 hrs prior to herbicide treatment. Experimental treatments included an
untreated control, and imazamox at 50 and 100 ppb of actual acid equivalent of
herbicide. Treatments were applied to water columns by the use of a pipette. Amount
of herbicide applied was based on the total volume of the cylinders (4000 ml). After
initial herbicide treatment, the water columns were gently stirred to ensure uniform
distribution. Treatments were arranged as a completely random design with 3
replications. Each cylinder was considered the experimental unit. Greenhouse
conditions were maintained at 24/18 °C (day/night) cycle for the duration of the
experiment. Natural day length was supplemented with halogen lighting to provide a 14
h photoperiod. Water level in the cylinders was periodically checked and maintained at
the 4000 ml level for the duration of the study. After 11 weeks of exposure, Hydrilla
shoot lengths were measured to ascertain herbicide effects. The results are given in
the following table.


Results showed that after the exposure period imazamox had a significant effect on the
growth of hydrilla. In addition to the growth suppression, visual symptomology included
reduction in plant vigour, chlorosis and reduction of intemodal length.
Intensity of symptoms tended to be rate responsive. The mixture of imazamox plus
quinclorac also showed significant effects.

We claim:
1. A method of controlling the aquatic weed Hydrilia verticillata which comprises
allowing a herbicidaliy effective amount of (RS)-2-(4-isopropyl-4-methyl-5-oxo-2-
imidazolin-2-yl)-5-methoxymethylnicotinic acid (imazamox) or an agriculturally
acceptable salt thereof to act on the aquatic weed and/or its aqueous habitat
containing seeds or other propagating organs of said aquatic weed.
2. The method as claimed in claim 1, wherein the aquatic weed Hydrilia
verticillata is resistant to the herbicide fluoridone.
3. The method as claimed in anyone of the preceding claims conducted in the
presence of rice plants.
4. The method as claimed in anyone of the preceding claims wherein the
imidazolinone herbizide is the R-enatiomer or the S-enatiomer of 2-(4-isopropyl-
4-methyl-5-oxo-2-imidazolin-2-yl)-5-methoxymethylnicotinic acid (imazamox).

5. The method as claimed in anyone of the preceding claims, wherein imazamox
is used in combination with one or more other herbicide(s).
6. The method as claimed in anyone of the preceding claims, wherein imazamox
is used in combination with one or more other herbicide(s) B selected from the
following classes b1)to b15):
b1) lipid biosynthesis inhibitors;
b2) acetolactate synthase inhibitors (ALS inhibitors);
b3) photosynthesis inhibitors;
b4) protoporphyrinogen-lX oxidase inhibitors;
b5) bleacher herbicides;
b6) enolpyruvyl shikimate 3-phosphate synthase inhibitors (EPSP
inhibitors);
b7) glutamine synthetase inhibitors;
b8) 7,8-dihydropteroate synthase inhibitors (DHP inhibitors);
b9) mitose inhibitors;
b10) inhibitors of the synthesis of long chain fatty acids (VLCFA inhibitors);
b11) cellulose biosynthesis inhibitors;
b12) decoupler herbicides;
b13) auxin herbicides;
b14) auxin transport inhibitors;

b 15) other herbicides selected from the group consisting of benzoylprop,
flamprop, fiamprop-M, bromobutide, chlorflurenol, cinmethylin,
methyldymuron, etobenzanid, fosamine, metam, pyributicarb,
oxaziclomefone, dazomet, triaziflam and methyl bromide;
all including the agriculturally acceptable salts and the agriculturally
acceptable derivatives thereof, provided they have a carboxyl group.

A method of controlling the aquatic weed Hydrilla verticillata which comprises allowing a herbicidally effective
amount of (RS)-2-(4-isopropyl-4-methyl-5-oxo-2-imidazolin-2-yl)-5-methoxymethylnicotinic acid (imazamox) or an agriculturally
acceptable salt thereof to act on the aquatic weed and/or its aqueous habitat containing seeds or other propagating organs of said
aquatic weed.

Documents:

02225-kolnp-2008-abstract.pdf

02225-kolnp-2008-claims.pdf

02225-kolnp-2008-description complete.pdf

02225-kolnp-2008-form 1.pdf

02225-kolnp-2008-form 3.pdf

02225-kolnp-2008-form 5.pdf

02225-kolnp-2008-international publication.pdf

02225-kolnp-2008-international search report.pdf

02225-kolnp-2008-pct priority document notification.pdf

02225-kolnp-2008-pct request form.pdf

2225-KOLNP-2008-(14-11-2013)-CORRESPONDENCE.pdf

2225-KOLNP-2008-(14-11-2013)-FORM-1.pdf

2225-KOLNP-2008-(14-11-2013)-FORM-13.pdf

2225-KOLNP-2008-(14-11-2013)-PA.pdf

2225-KOLNP-2008-(18-05-2012)-ABSTRACT.pdf

2225-KOLNP-2008-(18-05-2012)-AMANDED CLAIMS.pdf

2225-KOLNP-2008-(18-05-2012)-AMANDED PAGES OF SPECIFICATION.pdf

2225-KOLNP-2008-(18-05-2012)-DESCRIPTION (COMPLETE).pdf

2225-KOLNP-2008-(18-05-2012)-EXAMINATION REPORT REPLY RECEIVED.pdf

2225-KOLNP-2008-(18-05-2012)-FORM-2.pdf

2225-KOLNP-2008-(18-05-2012)-FORM-3.pdf

2225-KOLNP-2008-(18-05-2012)-FORM-5.pdf

2225-KOLNP-2008-(18-05-2012)-OTHERS.pdf

2225-KOLNP-2008-(18-05-2012)-PA-CERTIFIED COPIES.pdf

2225-KOLNP-2008-(18-05-2012)-PETITION UNDER RULE 137-1.pdf

2225-KOLNP-2008-(18-05-2012)-PETITION UNDER RULE 137.pdf

2225-KOLNP-2008-(23-07-2013)-CORRESPONDENCE.pdf

2225-KOLNP-2008-(24-09-2013)-ABSTRACT.pdf

2225-KOLNP-2008-(24-09-2013)-CLAIMS.pdf

2225-KOLNP-2008-(24-09-2013)-CORRESPONDENCE.pdf

2225-KOLNP-2008-(24-09-2013)-DESCRIPTION (COMPLETE).pdf

2225-KOLNP-2008-(24-09-2013)-OTHERS.pdf

2225-KOLNP-2008-ASSIGNMENT.pdf

2225-KOLNP-2008-CORRESPONDENCE 1.1.pdf

2225-KOLNP-2008-FORM 13.pdf

2225-kolnp-2008-form 18.pdf

2225-KOLNP-2008-FORM 3.1.pdf

2225-KOLNP-2008-GPA.pdf


Patent Number 257946
Indian Patent Application Number 2225/KOLNP/2008
PG Journal Number 47/2013
Publication Date 22-Nov-2013
Grant Date 21-Nov-2013
Date of Filing 03-Jun-2008
Name of Patentee BASF SE
Applicant Address 67056 LUDWIGSHAFEN
Inventors:
# Inventor's Name Inventor's Address
1 ZAWIERUCHA JOSEPH 100 HIGHFIELD AVENUE, CARY, NC 27519
2 EVANS, RICK 8412 LAKEWOOD DRIVE, RALEIGH, NC 27613
3 HORTON, TODD 128 LIFESTYLE LANE, ANDERSON, SC 29621
4 BERAN, DANIEL D. 1422 57TH PLACE, DES MOINES, IA 50311
5 VOLLMER, JOSEPH G. 2166 NOTH 15TH STREET, LARAMIE, WY 82072
6 BURNS, ALANE J-BO 5040 BARTONS ENCLAVE LN, RALEIGH, NC, 27613
7 BIRK, JEFFREY H. 2609 SUNYSTONE WAY, RALEIGH, NC, USA 27613
8 MILLER, DEREK W. 1504 REDWATER BRENNCHET, APEX, NC 22502
9 KNIGHT, TIMOTHY P. 7108 MANOR OAKS, RALEIGH, NC 27615
10 GLENN, OLIVER, W. 1001 OAKGATE COURT, 27502 APEX, NC
PCT International Classification Number A01N 43/50
PCT International Application Number PCT/EP2006/069861
PCT International Filing date 2006-12-18
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 60/752906 2005-12-23 U.S.A.