U.S. patent application number 13/219788 was filed with the patent office on 2012-03-01 for synergistic herbicidal composition containing penoxsulam and bentazon.
This patent application is currently assigned to DOW AGROSCIENCES LLC. Invention is credited to Richard K. Mann.
Application Number | 20120053055 13/219788 |
Document ID | / |
Family ID | 45698017 |
Filed Date | 2012-03-01 |
United States Patent
Application |
20120053055 |
Kind Code |
A1 |
Mann; Richard K. |
March 1, 2012 |
SYNERGISTIC HERBICIDAL COMPOSITION CONTAINING PENOXSULAM AND
BENTAZON
Abstract
A synergistic mixture of penoxsulam and bentazon controls weeds
in crops, especially rice and other cereal and grain crops,
pastures, rangelands, IVM and turf. In addition to providing
improved post-emergence herbicidal weed control, the mixture safens
damage to rice.
Inventors: |
Mann; Richard K.; (Franklin,
IN) |
Assignee: |
DOW AGROSCIENCES LLC
Indianapolis
IN
|
Family ID: |
45698017 |
Appl. No.: |
13/219788 |
Filed: |
August 29, 2011 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61378130 |
Aug 30, 2010 |
|
|
|
Current U.S.
Class: |
504/132 |
Current CPC
Class: |
A01N 43/88 20130101;
A01N 43/90 20130101; A01N 2300/00 20130101; A01N 43/90 20130101;
A01N 43/88 20130101; A01N 43/90 20130101 |
Class at
Publication: |
504/132 |
International
Class: |
A01N 43/90 20060101
A01N043/90; A01P 13/00 20060101 A01P013/00 |
Claims
1. A synergistic herbicidal mixture comprising an herbicidally
effective amount of (a) penoxsulam and (b) bentazon.
2. The synergistic herbicidal mixture of claim 1 in which bentazon
is an agriculturally acceptable salt.
3. The synergistic herbicidal mixture of claim 2 in which bentazon
is the sodium salt.
4. The synergistic herbicidal mixture of claim 1 in which the
weight ratio of bentazon to penoxsulam is between about 13:1 and
about 667:1.
5. An herbicidal composition comprising an herbicidally effective
amount of the synergistic herbicidal mixture of claim 1 and an
agriculturally acceptable adjuvant and/or carrier.
6. A method of controlling undesirable vegetation which comprises
contacting the vegetation or the locus thereof with or applying to
the soil or water to prevent the emergence or growth of vegetation
an herbicidally effective amount of the synergistic herbicidal
mixture of claim 1.
7. A method of claim 6 for controlling undesirable vegetation in
crops, especially rice and other cereal and grain crops, pastures,
rangelands, IVM, aquatics and turf, which comprises contacting the
vegetation or the locus thereof with or applying to the soil or
water to prevent the emergence or growth of vegetation an
herbicidally effective amount of the synergistic herbicidal mixture
comprising an herbicidally effective amount of (a) penoxsulam and
(b) bentazon.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional
Patent Application Ser. No. 61/378,130 filed Aug. 30, 2010.
FIELD OF THE INVENTION
[0002] This invention concerns a synergistic herbicidal composition
containing (a) penoxsulam and (b) bentazon for controlling weeds in
crops, especially rice, cereal and grain crops, pastures,
rangelands, industrial vegetation management (IVM), aquatics and
turf. These compositions are disclosed as providing improved
post-emergence herbicidal weed control and improved safening on
rice.
BACKGROUND OF THE INVENTION
[0003] The protection of crops from weeds and other vegetation
which inhibit crop growth is a constantly recurring problem in
agriculture. To help combat this problem, researchers in the field
of synthetic chemistry have produced an extensive variety of
chemicals and chemical formulations effective in the control of
such unwanted growth. Chemical herbicides of many types have been
disclosed in the literature and a large number are in commercial
use.
[0004] In some cases, herbicidal active ingredients have been shown
to be more effective in combination than when applied individually
and this is referred to as "synergism." As described in the
Herbicide Handbook of the Weed Science Society of America, Ninth
Edition, 2007, p. 429 "`synergism` [is] an interaction of two or
more factors such that the effect when combined is greater than the
predicted effect based on the response to each factor applied
separately." The present invention is based on the discovery that
penoxsulam and bentazon, already known individually for their
herbicidal efficacy, display a synergistic effect when applied in
combination.
SUMMARY OF THE INVENTION
[0005] The present invention concerns a synergistic herbicidal
mixture comprising an herbicidally effective amount of (a)
penoxsulam and (b) bentazon. The compositions may also contain an
agriculturally acceptable adjuvant and/or carrier.
[0006] The present invention also concerns herbicidal compositions
for and methods of controlling the growth of undesirable
vegetation, particularly in monocot crops including rice, wheat,
barley, oats, rye, sorghum, corn, maize, pastures, grasslands,
rangelands, fallowland, turf, IVM and aquatics, and the use of
these synergistic compositions.
[0007] The species spectra of penoxsulam and bentazon, i.e., the
weed species which the respective compounds control, are broad and
highly complementary. It has now been found that a combination of
penoxsulam and bentazon exhibits a synergistic action in the
control of rice flatsedge (Cyperus iria; CYPIR); arrowhead
(Sagittaria trifolia; SAGTR); and barnyardgrass (Echinochloa
crus-galli; ECHCG) at application rates equal to or lower than the
rates of the individual compounds. It has also been found that a
combination of penoxsulam and bentazon exhibits a safening effect
on rice (Orysa sativa; ORYSA).
DETAILED DESCRIPTION OF THE INVENTION
[0008] Bentazon is the common name for
3-(1-methylethyl)-1H-2,1,3-benzothiadiazin-4(3H)-one 2,2-dioxide.
Its herbicidal activity is described in The Pesticide Manual,
Fifteenth Edition, 2009. Bentazon controls a wide range of
economically important broadleaf and sedge weeds. It can be used as
the acid itself or as an agriculturally acceptable salt or ester.
Use as a salt is preferred, with the sodium salt being most
preferred. Bentazon is also known as bentazone and bendioxide.
[0009] Penoxsulam is the common name for
2-(2,2-difluoroethoxy)-N-(5,
8-dimethoxy-[1,2,4]triazolo[1,5-c]pyrimidin-2-yl)-6-(trifluoromethyl)benz-
enesulfonamide. Its herbicidal activity is described in The
Pesticide Manual, Fifteenth Edition, 2009. Penoxsulam controls
Echinochloa spp., as well as many broadleaf, sedge and aquatic
weeds in rice, and Apera spp. grass in cereals, as well as many
broadleaf weeds in aquatics, many cereal crops, range and pasture,
IVM and turf.
[0010] The term herbicide is used herein to mean an active
ingredient that kills, controls or otherwise adversely modifies the
growth of plants. An herbicidally effective or vegetation
controlling amount is an amount of active ingredient which causes
an adversely modifying effect and includes deviations from natural
development, killing, regulation, desiccation, retardation, and the
like. The terms plants and vegetation include germinant seeds,
emerging seedlings, plants emerging from vegetative propagules, and
established vegetation.
[0011] Herbicidal activity is exhibited by the compounds of the
synergistic mixture when they are applied directly to the plant, to
the locus of the plant at any stage of growth or before planting or
emergence or after emergence. The effect observed depends upon the
plant species to be controlled, the stage of growth of the plant,
the application parameters of dilution and spray drop size, the
particle size of solid components, the environmental conditions at
the time of use, the specific compound employed, the specific
adjuvants and carriers employed, the soil type, and the like, as
well as the amount of chemical applied. These and other factors can
be adjusted as is known in the art to promote non-selective or
selective herbicidal action. Generally, it is preferred to apply
the composition of the present invention postemergence to
relatively immature undesirable vegetation to achieve the maximum
control of weeds.
[0012] In the composition of this invention, the weight ratio of
bentazon-sodium to penoxsulam at which the herbicidal effect is
synergistic lies within the range of between about 13:1 and about
667:1. The rate at which the synergistic composition is applied
will depend upon the particular type of weed to be controlled, the
degree of control required, and the timing and method of
application. In general, the composition of the invention can be
applied at an application rate of between about 303 grams per
hectare (g/ha) and about 2050 g/ha based on the total amount of
active ingredients in the composition. Penoxsulam is applied at a
rate between about 3 g/ha and about 50 g/ha and bentazon is applied
at a rate between about 300 g/ha and about 2000 g/ha.
[0013] The components of the synergistic mixture of the present
invention can be applied either separately or as part of a
multipart herbicidal system.
[0014] The synergistic mixture of the present invention can be
applied in conjunction with one or more other herbicides to control
a wider variety of undesirable vegetation. When used in conjunction
with other herbicides, the composition can be formulated with the
other herbicide or herbicides, tank mixed with the other herbicide
or herbicides or applied sequentially with the other herbicide or
herbicides. Some of the herbicides that can be employed in
conjunction with the synergistic composition of the present
invention include: 2,4-D, acetochlor, acifluorfen, aclonifen,
AE0172747, alachlor, ametryn, amidosulfuron, aminocyclopyrachlor,
aminopyralid, aminotriazole, amitrol, ammonium thiocyanate,
anilifos, asulam, atrazine, azimsulfuron, beflubutamid, benazolin,
benefin, benfuresate, bensulfuron, bensulide, benthiocarb,
benzobicyclon, benzofenap, bifenox, bispyribac, bromacil,
bromobutide, bromoxynil, butachlor, butafenacil, butralin,
cafenstrole, carbetamide, carfentrazone, chlorflurenol,
chlorimuron, chlormequat, chlorpropham, chlortoluron, cinidon,
cinosulfuron, clethodim, clodinafop, clomazone, clomeprop,
clopyralid, cloransulam, cumyluron, cyanazine, cyclosulfamuron,
cycloxydim, cyhalofop, daimuron, dicamba, dichlobenil, dichlorprop,
diclofop, diclosulam, diflufenican, diflufenzopyr, dimefuron,
dimepiperate, dimethametryn, dimethenamid, dimethenamid, diquat,
dithiopyr, diuron, EK2612, EPTC, erioglaucine, esprocarb, ET-751,
ethofumesate, ethoxysulfuron, ethbenzamide, etobenzanid, F7967,
fenoxaprop, fentrazamide, flazasulfuron, florasulam, fluazifop,
flucarbazone, flucetosulfuron (LGC-42153), flufenacet, flufenpyr,
flumetsulam, flumiclorac, flumioxazin, fluometuron, flupyrsulfuron,
fluroxypyr, flurtamone, fosamine, fomesafen, foramsulfuron,
fumiclorac, glufosinate, glyphosate, halosulfuron, haloxyfop,
hexazinone, imazamethabenz, imazamox, imazapic, imazapyr,
imazaquin, imazethapyr, imazosulfuron, indanofan, indaziflam,
iodosulfuron, ioxynil, ipfencarbazone (HOK-201), IR 5790,
isoproturon, isoxaben, isoxaflutole, KUH-071, lactofen, linuron,
MCPA, mecoprop, mefenacet, mesosulfuron, mesotrione, metamifop,
metazosulfuron (NC-620), metolachlor, metosulam, metribuzin,
metsulfuron, molinate, monosulfuron, MSMA, napropamide,
nicosulfuron, norflurazon, OK-9701, orthosulfamuron, oryzalin,
oxadiargyl, oxadiazon, oxazichlomefone, oxyfluorfen, paraquat,
pendimethalin, pentoxazone, pethoxamid, picloram, picolinafen,
pinoxaden, piperophos, pretilachlor, primisulfuron, prodiamine,
profluazol, profoxydim, prohexadione, prometon, pronamide,
propachlor, propanil, propisochlor, propoxycarbazone,
propyrisulfuron (TH-547), propyzamide, prosulfocarb, prosulfuron,
pyrabuticarb, pyraclonil, pyraflufen, pyrazogyl, pyrazolynate,
pyrazosulfuron, pyrazoxyfen, pyribenzoxim (LGC-40863), pyridate,
pyriftalid, pyriminobac, pyrimisulfan (KUH-021), pyrithiobac,
pyroxasulfone (KIH-485), pyroxsulam, quinclorac, quinmerac,
quinoclamine, quizalofop, rimsulfuron, S-3252, saflufenacil,
sethoxydim, simazine, simetryne, SL-0401, SL-0402, sulcotrione,
sulfentrazone, sulfometuron, sulfosate, sulfosulfuron, tebuthiuron,
tefuryltrione (AVH-301), terbacil, thenylchlor, thiazopyr,
thiencarbazone, thifensulfuron, thiobencarb, topramezone,
tralkoxydim, triasulfuron, tribenuron, triclopyr, trifloxysulfuron,
trifluralin, trinexapac, tritosulfuron and salts, esters, optically
active isomers and mixtures thereof.
[0015] The synergistic composition of the present invention can,
further, be used in conjunction with glyphosate, glufosinate,
dicamba, imidazolinones, sulfonylureas, or 2,4-D on
glyphosate-tolerant, glufosinate-tolerant, dicamba-tolerant,
imidazolinone-tolerant, sulfonylurea-tolerant and 2,4-D-tolerant
crops. It is generally preferred to use the synergistic composition
of the present invention in combination with herbicides that are
selective for the crop being treated and which complement the
spectrum of weeds controlled by these compounds at the application
rate employed. It is further generally preferred to apply the
synergistic composition of the present invention and other
complementary herbicides at the same time, either as a combination
formulation or as a tank mix.
[0016] The synergistic composition of the present invention can
generally be employed in combination with known herbicide safeners,
such as benoxacor, benthiocarb, brassinolide, cloquintocet (mexyl),
cyometrinil, daimuron, dichlormid, dicyclonon, dimepiperate,
disulfoton, fenchlorazole-ethyl, fenclorim, flurazole, fluxofenim,
furilazole, isoxadifen-ethyl, mefenpyr-diethyl, MG 191, MON 4660,
naphthalic anhydride (NA), oxabetrinil, R29148 and
N-phenyl-sulfonylbenzoic acid amides, to enhance their
selectivity.
[0017] The synergistic mixture of penoxsulam and bentazon of the
present invention also provides a safening effect when applied to
rice.
[0018] In practice, it is preferable to use the synergistic
composition of the present invention in mixtures containing an
herbicidally effective amount of the herbicidal components along
with at least one agriculturally acceptable adjuvant or carrier.
Suitable adjuvants or carriers should not be phytotoxic to valuable
crops, particularly at the concentrations employed in applying the
compositions for selective weed control in the presence of crops,
and should not react chemically with herbicidal components or other
composition ingredients. Such mixtures can be designed for
application directly to weeds or their locus or can be concentrates
or formulations that are normally diluted with additional carriers
and adjuvants before application. They can be solids, such as, for
example, dusts, granules, water dispersible granules, or wettable
powders, or liquids, such as, for example, emulsifiable
concentrates, solutions, emulsions or suspensions.
[0019] Suitable agricultural adjuvants and carriers that are useful
in preparing the herbicidal mixtures of the invention are well
known to those skilled in the art. Some of these adjuvants include,
but are not limited to, crop oil concentrate (mineral oil
(85%)+emulsifiers (15%)); nonylphenol ethoxylate;
benzylcocoalkyldimethyl quaternary ammonium salt; blend of
petroleum hydrocarbon, alkyl esters, organic acid, and anionic
surfactant; C.sub.9-C.sub.11 alkylpolyglycoside; phosphated alcohol
ethoxylate; natural primary alcohol (C.sub.12-C.sub.16) ethoxylate;
di-sec-butylphenol EO-PO block copolymer; polysiloxane-methyl cap;
nonylphenol ethoxylate+urea ammonium nitrate; emulsified methylated
seed oil; tridecyl alcohol (synthetic) ethoxylate (8EO); tallow
amine ethoxylate (15 EO); PEG(400) dioleate-99.
[0020] Liquid carriers that can be employed include water and
organic solvents. The organic solvents typically used include, but
are not limited to, petroleum fractions or hydrocarbons such as
mineral oil, aromatic solvents, paraffinic oils, and the like;
vegetable oils such as soybean oil, rapeseed oil, olive oil, castor
oil, sunflower seed oil, coconut oil, corn oil, cottonseed oil,
linseed oil, palm oil, peanut oil, safflower oil, sesame oil, tung
oil and the like; esters of the above vegetable oils; esters of
monoalcohols or dihydric, trihydric, or other lower polyalcohols
(4-6 hydroxy containing), such as 2-ethyl hexyl stearate, n-butyl
oleate, isopropyl myristate, propylene glycol dioleate, di-octyl
succinate, di-butyl adipate, di-octyl phthalate and the like;
esters of mono, di and polycarboxylic acids and the like. Specific
organic solvents include toluene, xylene, petroleum naphtha, crop
oil, acetone, methyl ethyl ketone, cyclohexanone,
trichloroethylene, perchloroethylene, ethyl acetate, amyl acetate,
butyl acetate, propylene glycol monomethyl ether and diethylene
glycol monomethyl ether, methyl alcohol, ethyl alcohol, isopropyl
alcohol, amyl alcohol, ethylene glycol, propylene glycol,
glycerine, N-methyl-2-pyrrolidinone, N,N-dimethyl alkylamides,
dimethyl sulfoxide, liquid fertilizers and the like. Water is
generally the carrier of choice for the dilution of
concentrates.
[0021] Suitable solid carriers include talc, pyrophyllite clay,
silica, attapulgus clay, kaolin clay, kieselguhr, chalk,
diatomaceous earth, lime, calcium carbonate, bentonite clay,
Fuller's earth, cottonseed hulls, wheat flour, soybean flour,
pumice, wood flour, walnut shell flour, lignin, and the like.
[0022] It is usually desirable to incorporate one or more
surface-active agents into the compositions of the present
invention. Such surface-active agents are advantageously employed
in both solid and liquid compositions, especially those designed to
be diluted with carrier before application. The surface-active
agents can be anionic, cationic or nonionic in character and can be
employed as emulsifying agents, wetting agents, suspending agents,
or for other purposes. Surfactants conventionally used in the art
of formulation and which may also be used in the present
formulations are described, inter alia, in "McCutcheon's Detergents
and Emulsifiers Annual," MC Publishing Corp., Ridgewood, N.J., 1998
and in "Encyclopedia of Surfactants," Vol. I-III, Chemical
Publishing Co., N.Y., 1980-81. Typical surface-active agents
include salts of alkyl sulfates, such as diethanolammonium lauryl
sulfate; alkylarylsulfonate salts, such as calcium
dodecylbenzenesulfonate; alkylphenol-alkylene oxide addition
products, such as nonylphenol-C.sub.18 ethoxylate; alcohol-alkylene
oxide addition products, such as tridecyl alcohol-C.sub.16
ethoxylate; soaps, such as sodium stearate;
alkylnaphthalene-sulfonate salts, such as sodium
dibutyl-naphthalenesulfonate; 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; salts of mono and dialkyl
phosphate esters; vegetable or seed oils such as soybean oil,
rapeseed/canola oil, olive oil, castor oil, sunflower seed oil,
coconut oil, corn oil, cottonseed oil, linseed oil, palm oil,
peanut oil, safflower oil, sesame oil, tung oil and the like; and
esters of the above vegetable oils, particularly methyl esters.
[0023] Oftentimes, some of these materials, such as vegetable or
seed oils and their esters, can be used interchangeably as an
agricultural adjuvant, as a liquid carrier or as a surface active
agent.
[0024] Other additives commonly used in agricultural compositions
include compatibilizing agents, antifoam agents, sequestering
agents, neutralizing agents and buffers, corrosion inhibitors,
dyes, odorants, spreading agents, penetration aids, sticking
agents, dispersing agents, thickening agents, freezing point
depressants, antimicrobial agents, and the like. The compositions
may also contain other compatible components, for example, other
herbicides, plant growth regulants, fungicides, insecticides, and
the like and can be formulated with liquid fertilizers or solid,
particulate fertilizer carriers such as ammonium nitrate, urea and
the like.
[0025] The concentration of the active ingredients in the
synergistic composition of the present invention is generally from
0.1 to 98 percent by weight. Concentrations from 10 to 90 percent
by weight are often employed. In compositions designed to be
employed as concentrates, the active ingredients are generally
present in a concentration from 5 to 98 weight percent, preferably
10 to 90 weight percent. Such compositions are typically diluted
with an inert carrier, such as water, before making a
postemergence, foliar application to exposed weed and crop foliage,
or applied as a dry or liquid formulation directly into flooded
rice fields. The diluted compositions usually applied as a
postemergence, foliar application to weeds or the locus of weeds
generally contain 0.25 to 20 weight percent active ingredient and
preferably contain 0.4 to 14 weight percent.
[0026] The present compositions can be applied to weeds or their
locus by the use of conventional ground or aerial dusters,
sprayers, and granule applicators, by addition to irrigation or
paddy water, and by other conventional means known to those skilled
in the art.
[0027] The following examples illustrate the present invention.
[0028] Evaluation of Postemergence Herbicidal Activity of Mixtures
in the Greenhouse
[0029] Seeds of the desired test plant species were planted in 80%
mineral soil/20% grit planting mixture, which typically has a pH of
7.2 and an organic matter content of approximately 3 percent, in
plastic pots with a surface area of 128 square centimeters
(cm.sup.2). The growing medium was steam sterilized. The plants
were grown for 7-19 days (d) in a greenhouse with an approximate
14-hour (h) photoperiod which was maintained at about 29.degree. C.
during the day and 26 .degree. C. during the night. Nutrients and
water were added on a regular basis and supplemental lighting was
provided with overhead metal halide 1000-Watt lamps as necessary.
The plants were treated with postemergence foliar applications when
they reached the second to fourth true leaf stage. All treatments
were applied using a randomized complete block trial design, with 4
replications per treatment.
[0030] Treatments consisted of the compounds as listed in Tables 1
and 3, each compound applied alone and in combination. Formulated
amounts of penoxsulam and bentazon, were placed in 60 milliliter
(mL) glass vials and dissolved in a volume of 60 mL of a water
solution containing Agri-dex crop oil concentrate in a 1% v/v
ratio. Compound requirements are based upon a 12 mL application
volume at a rate of 187 liters per hectare (L/ha). Spray solutions
of the mixtures were prepared by adding the stock solutions to the
appropriate amount of dilution solution to form a 12 mL spray
solution with active ingredients in single and two way
combinations. Formulated compounds were applied to the plant
material with an overhead Mandel track sprayer equipped with 8002E
nozzles calibrated to deliver 187 L/ha at a spray height of 18
inches (43 centimeters (cm)) above average plant canopy.
[0031] The treated plants and control plants were placed in a
greenhouse as described above and watered by sub-irrigation to
prevent wash-off of the test compounds. Treatments were rated at 7
to 21 d after application as compared to the untreated control
plants. Visual weed control was scored on a scale of 0 to 100
percent where 0 corresponds to no injury and 100 corresponds to
complete kill.
[0032] Evaluation of Postemergence Herbicidal Activity of Mixtures
in the Field
[0033] Field trials were conducted in rice using standard herbicide
small plot research methodology. Plots varied from 3.times.3 meter
(m) to 3.times.10 m (width.times.length) with 4 replicates per
treatment. The rice crop was grown using normal cultural practices
for fertilization, seeding, watering, flooding and maintenance to
ensure good growth of the crop and the weeds.
[0034] All treatments in the field trials were applied using a
CO.sub.2 backpack sprayer calibrated to apply 187 L/ha spray
volume. Commercially available products of penoxsulam and bentazon
were mixed in water at appropriate formulated product rates to
achieve the desired rates based on a unit area of application
(hectare) to achieve the desired rates as shown. Treatments were
rated at 6 to 45 d after application as compared to the untreated
control plants. Visual weed control was scored on a scale of 0 to
100 percent where 0 corresponds to no injury and 100 corresponds to
complete kill.
[0035] Tables 1 and 2 demonstrate the herbicidal synergistic
efficacy of penoxsulam+bentazon-sodium tank mixes on weed control.
Table 3 demonstrates the herbicidal synergistic safening of two
crops to mixtures of penoxsulam+bentazon-sodium. All treatment
results, both for the single product and mixtures, are an average
of 3 to 4 replicates and the tank mix interactions are significant
at the P>0.05 level.
[0036] Colby's equation was used to determine the herbicidal
effects expected from the mixtures (Colby, S.R. Calculation of the
synergistic and antagonistic response of herbicide combinations.
Weeds 1967, 15, 20-22.).
[0037] The following equation was used to calculate the expected
activity of mixtures containing two active ingredients, A and
B:
Expected=A+B-(A.times.B/100)
[0038] A=observed efficacy of active ingredient A at the same
concentration as used in the mixture.
[0039] B=observed efficacy of active ingredient B at the same
concentration as used in the mixture.
[0040] Some of the compounds tested, application rates employed,
plant species tested, and results are given in Tables 1-3. All
comparisons are an average of 3 to 4 replicates and are significant
at the P>0.05 level.
TABLE-US-00001 TABLE 1 Synergistic Activity of Herbicidal
Compositions on Sedge Weeds (Cyperus iria; CYPIR) in the Greenhouse
at 21 Days after Application Application Rate (g/ha) % Control
Bentazon- CYPIR Penoxsulam Sodium Ob Ex 3 0 20 0 500 55 3 500 85 64
3 0 20 0 1000 72 3 1000 98 78
TABLE-US-00002 TABLE 2 Synergistic Activity of Herbicidal
Compositions on Broadleaf and Grass Weeds Sagittaria trifolia
(SAGTR) and Echinochloa crus- galli (ECHCG) in the Field at 6 to 45
Days after Application % Control Application Rate (g/ha) Bentazon-
SAGTR ECHCG Penoxsulam Sodium Ob Ex Ob Ex 15 0 38 -- -- -- 0 1100
78 -- -- -- 15 1100 100 87 -- -- 23 0 45 -- -- -- 0 1100 78 -- --
-- 23 1100 100 88 -- -- 38 0 -- -- 30 -- 0 2000 -- -- 0 -- 38 2000
-- -- 53 30
TABLE-US-00003 TABLE 3 Activity of Herbicidal Compositions on
Safening of Injury in Rice (ORYSA) in the Greenhouse at 21 Days
after Application Application Rate (g/ha) % Control Bentazon- ORYSA
Penoxsulam sodium Ob Ex 7.5 0 0 -- 0 500 14 -- 7.5 500 2.5 14 15 0
0 -- 0 500 14 -- 15 500 0 14 7.5 0 0 -- 0 1000 16 -- 7.5 1000 0 16
15 0 0 -- 0 1000 16 -- 15 1000 0 16
* * * * *