FIELD OF THE INVENTION
The present invention relates to new herbicidal compositions and methods related
thereto. More particularly, the present invention relates to agrochemical compositions,
comprising a pyrimidinyloxybenzoate in a synergistic combination with an
aryloxyphenoxypropionate and the method of preparation and use thereof as herbicides
for the control of weeds in agricultural crops, in particular weeds flora in rice.
BACKGROUND OF THE INVENTION
Weeds damage agricultural crops and adversely affect crop productivity by competing
with the crop for mineral nutrients, nitrogen, water, and sunlight. Several herbicides and
methods of using such herbicides to control weed species are known in the art.
Chemical herbicides are typically categorized according to the time of application (e.g.,
pre-emergence or post-emergence herbicides). Pre-emergence herbicides are applied
prior to germination of weed for control of germinating seeds without harming the
desired plant species. Post-emergence herbicides are applied after planting and over
the top of establishing or established plants for control of weed species.
Moreover, current methods of attempting to control weeds include applications of preemergent
herbicides followed by post emergent herbicides i.e. sequential applications of
herbicides to address the issue of weeds in agricultural crop cultivation. Most of the rice
lands under cultivation are weeded by hand, hence, significant human effort and time
are expended in raising rice. Most of the times, the dosage used varies as the herbicide
selection is not based on the technical knowhow which results in poor weed control
affecting the productivity of the crop. Additionally, farmers are using different herbicidal
combinations without knowing the mode of action and the weed spectrum. Due to lack
of knowledge, there is inappropriate and/or under dosage of the weed products and this
frequently leads to resistance development or poor control of the weeds. Similarly, other
conventional methods of producing agricultural crops include the use of different
combinations of herbicides such as tank mix herbicides to address the issue of emerged
3
weeds without having proper application knowledge of the weed spectrum individual
herbicides. In such usage the chances of varied dosage of individual herbicides end up
with poor weed control, phytotoxicity on rice crop resulting in poor productivity.
Therefore, successful weed management is essential for economical rice production.
Furthermore, environmental considerations increasingly require that lower amounts of
herbicidally active substances be used in the control of undesired vegetation.
It is known to overcome this type of problem to some extent by the use of herbicidal
compositions in which more than one type of herbicide is present. Such compositions,
however, should preferably still show the advantageous properties of the individual
herbicide constituents and display a synergistic effect between them, whilst maintaining
selectivity of herbicidal action with respect to the crop. It is, nonetheless, difficult to
determine appropriate combinations of herbicides in view of the considerable number of
different types of herbicides available and the plurality of individual herbicides within
each such type.
Herbicides used in rice weed management and the issues related with the weed control
are shown in the below Table 1:
Herbicide Trade name Formulation Formulation
Dosage/ha
Rice segment
Usage
Issues
Pretilachlor Rifit 50 % EC 1-1.25L Transplanted Weed control is poor if
water management is
not good
Butachlor Machette 50% EC 2.5 L Transplanted Not good on Broad
leaved weeds
Metasulfuron
Methyl 10% +
Chlorimuron Ethyl
10% WP
Almix 20% WP 20 gm Transplanted
and nursery
and DSR
Weak on grasses
Cyhalofop butyl Clincher 10% EC 800 ml Nursery Does not control
Broadleaved weeds
and sedges
Pretilachlor Sofit 30% EC 1.25 L Nursery and
direct seeded
Weed control is poor if
water management is
not good
Ethoxysulfuron Sunrice 15% WDG 100 gm Transplanted,
DSR
Does not control
grasses
Pyrazosulfuron Saathi 10% WP 200 gm Transplanted,
Nursery, DSR
Weak on grasses
2,4 D Sodium salt Weedmar 80% WP 1KG Transplanted,
DSR
Weak on grasses
2,4 D ethyl ester Weedmar38 38% EC 2.5 L Transplanted,
DSR
Weak on grasses
Oxadiargyl Topstar 80% WP 87.5 Transplanted Weed control is poor if
water management is
not good
4
Bensulfuron
methyl 0.6 % +
Pretilachlor 6 %
Londax Power 6.6% 10 kg Transplanted Weed control is poor if
water management is
not good
Bispyribac sodium Bispyribac
sodium
10% SC 200 ML Transplanted,
DSR, Nursery
Fenoxyprop-Pethyl
Whipsuper 10% EC 750 ML DSR Only good on grasses
but phytotoxicity
issues are there.
Table 1
The herbicides or combination of herbicides can be applied in different ways for
example sequential application, tank-mix application and pre-mix application. In
sequential application, farmers use different herbicides, wherein the herbicide selection
is not based on the technical knowhow and herbicides having the same mode of action
are being used, which leads to resistance development. In tank-mix application, farmers
use different combinations of herbicides, most of the times without having training to
properly mix products. Homemade tank mixes may therefore not be as stable as a premix.
The tank-mix usually results in non-judicious use of individual herbicides and end
up with poor pest control. Moreover, the tank mixture is less convenient and potentially
hazardous to people who are not trained to properly mix products.
The pre-mix application is a combination of two or more herbicides as active ingredients
but the rates of the active ingredients are unchangeable, the components rates and
formulation are optimized during development, hence no mixing or stability issue exists.
The pre-mix application also helps in reducing the development of herbicides
resistance.
The sequential application and tank-mix application of herbicides, when employed to
address weed flora in rice, result in development of herbicide resistance. The pre-mix
application being convenient to use have not been applied so far for management of
crop e.g. weed flora in soybean and wheat crop. It has been found that the combination
of a pyrimidinyloxybenzoate preferably sodium 2,6-bis[(4,6-dimethoxy-2-
pyrimidinyl)oxy]benzoate (Bispyribac sodium) and a aryloxyphenoxy-propionate
preferably ethyl (2R)2[
4[(
6chloro1,
3benzoxazol2yl)
oxy]phenoxy]propanoate
(Fenoxaprop-p-ethyl) provides synergies in controlling weeds of rice crop and also
contributes in Herbicide Resistance Management (HRM).
5
It is therefore desired to provide an improved composition and convenient method which
safely and effectively control and eventually eliminate unwanted weedy species from the
agricultural crops and therefore, there is a constant need for the development and
application of synergistic formulations which are not only effective in weed control, but
also help in increasing the yield of crop.
SUMMARY AND OBJECTS OF THE INVENTION
In one aspect, the invention relates to a stable, synergistic composition comprising a
pyrimidinyloxybenzoate and an aryloxyphenoxy-propionate that results in an enhanced
herbicidal activity, in particular a combination of a pyrimidinyloxybenzoate preferably
sodium 2,6-bis[(4,6-dimethoxy-2-pyrimidinyl)oxy]benzoate (Bispyribac sodium) and a
aryloxyphenoxy-propionate preferably ethyl (2R)2[
4[(
6chloro1,
3benzoxazol2yl)
oxy]phenoxy]propanoate (Fenoxaprop-p-ethyl) provides synergies in
controlling weeds of rice crop and also contributes in Herbicide Resistance
Management (HRM) for sustainability of the life of this chemistry.
This composition for weed control for crop such as rice is advantageous, for several
reasons some of which are as follows:
- allows for a wider application window such as greater flexibility in timing of
application spanning over 12 to 35 days;
- has a synergistic effect useful for addressing broad weed spectrum;
- required to be administered in lower dosage strength and lower dosage
frequency;
- since the two herbicide compounds belong to different classes of herbicides, the
said composition is useful for management of Herbicide Resistance
6
- useful for the pre and post emergence control of a number of both monocot and
di-cot weed species with a single application of the synergistic combination;
- provides for enhanced control of weed spectrum through premix application;
- a single solution for different rice segments such as, nursery, transplanted, direct
seeded rice with a wider application window.
In another aspect, the present invention provides for a method of preparation of
composition comprising a pyrimidinyloxybenzoate and an aryloxyphenoxy-propionate.
Accordingly, it is an object and advantage of the present invention to provide a stable,
synergistic and novel composition comprising a pyrimidinyloxybenzoate and an
aryloxyphenoxypropionate.
A further object of the present invention is to provide an herbicidal composition that
efficaciously contributes in Herbicide Resistance Management (HRM).
Another object and advantage of the present invention is to provide a stable synergistic
herbicidal composition that shows technical advancement over the existing herbicides
or combination of herbicides.
Yet another object and advantage of the present invention is to provide a composition
that can be applied over a prolonged period of application and which is simple in use
without need of strict requirements allowing for a wider application window that thus
allows broader spectrum of weed control.
Another object and advantage of the present invention is to provide an economical and
cost-effective composition for management and control of weeds.
Yet another object and advantage of the present invention is to provide a cost-effective
and convenient method for the preparation of said composition, which is effective
7
against a wide variety of weeds in crops, especially for management of weed flora in
rice.
Another object and advantage of the present invention is to provide a stable synergistic
herbicidal composition which meets the environmental and economic requirements
imposed on modern-day herbicides which are continually increasing, with regard, for
example, to the spectrum of action, toxicity, selectivity, application rate, formation of
residues, low costs and favorable preparation ability.
The above and other objects will become more apparent in view of the description given
below.
DETAILED DESCRIPTION OF THE INVENTION
The compositions or formulation according to the present invention are effective in the
post-emergence of numerous monocotyledonous and dicotyledonous weeds.
Accordingly, the present invention relates to a stable synergistic agrochemical
composition for management of weed flora in rice comprising a pyrimidinyloxybenzoate
(A) and an aryloxyphenoxy-propionate (B) and agriculturally acceptable formulation
additives (C) wherein the weight percentage of (A) is 3 to 29%, weight percentage of (B)
is 7 to 66% and weight percentage of (C) is 5 to 90%.
Accordingly, the present invention relates to a stable synergistic agrochemical
composition for management of weed flora in rice comprising a pyrimidinyloxybenzoate
(A) and an aryloxyphenoxy-propionate (B) and agriculturally acceptable formulation
additives (C) wherein the weight percentage of (A) is 3 to 15%, weight percentage of (B)
is 7 to 35% and weight percentage of (C) is 10 to 50% .
The present invention comprising a pyrimidinyloxybenzoate and an aryloxyphenoxypropionate
can be mixed in a wide ratio, in relation to various factors such as, for
8
example the weeds to be controlled, the degree of infestation, the climatic conditions,
the characteristics of the soil and the application method.
For practical use in agriculture, the composition or formulation of the present invention
can be applied in such quantities as to guarantee applicative dosages of the synergistic
combination.
The compositions of the present invention are suitable for controlling a large number of
harmful plants, including monocotyledonous weeds, in particular annual weeds such as
gramineous weeds (grasses) including Echinochloa species such as barnyardgrass
(Echinochloa crusgalli var. crus-galli), Digitaria species such as crabgrass (Digitaria
sanguinalis), Setaria species such as green foxtail (Setaria viridis) and giant foxtail
(Setaria faberii), Sorghum species such as Johnson grass (Sorghum halepense Pers.),
Cenchrus species such as Cenchrus echinatus, Bromus species, Eriochloa species,
Panicum species, Brachiaria species, annual bluegrass (Poa annua), blackgrass
(Alopecurus myosuroides), Aegilops cylindrica, Agropyron repens, Apera spica-venti,
Eleusine indica, Cynodon dactylon and the like.
The compositions of the present invention are also suitable for controlling a large
number of dicotyledonous weeds, in particular broad leaf weeds including Sphenoclea
zeylanica, Eclipta alba, Ludwigia parviflora, Ammannia baccifera, Physalis minima,
Alternanthera sp., Solanum sp. Euphorbia sp., Cassia sp. Amaranthus species such as
pigweed (Amaranthus retroflexus), Sida species such as prickly sida (Sida spinosa L.),
Ambrosia species such as common ragweed (Ambrosia artemisiifolia),
Acanthospermum species, Anthemis species, Atriplex species, Cirsium species,
Conyza species, Cassia species, Commelina species, Datura species, Euphorbia
species, Geraniumspecies, Galinsoga species, morning glory (Ipomoea species),
Lamium specie, Matricaria species, Sysimbrium species, Solanum species, Xanthium
species, Veronica species, Viola species, common chickweed (Stellaria media),
velvetleaf (Abutilon theophrasti), Hemp sesbania (Sesbania exaltata Cory), and the like.
9
The compositions of the present invention are also suitable for controlling a large
number of annual and perennial sedge weeds including cyperus species such as purple
nut sedge (Cyperus rotundus L.), yellow nut sedge (Cyperus esculentus L.), hime-kugu
(Cyperus brevifolius H.), sedge weed (Cyperus micro-iria Steud), rice flat sedge
(Cyperus iria L.), and the like.
The compositions of the present invention are in particular suitable for controlling weeds
of rice crop (direct seeded rice as well as transplanted rice). The compositions can be
applied post-emergence, i.e. after emergence of the weeds.
It is a particular benefit of the compositions according to the invention that they have a
very good post-emergence herbicidal activity. Thus, in a preferred embodiment of
invention, the compositions are applied post-emergence, i.e. during and/or after, the
emergence of the weeds. It is particularly advantageous to apply the mixtures according
to the invention as post emergent when the weeds start with leaf development up to
flowering. Since the composition show good crop tolerance, even when the crop has
already emerged, they can be applied after seeding of the crop plants and in particular
during or after the emergence of the crop plants.
The present invention also relates to formulations of the compositions according to the
present invention. The formulations contain, besides the composition, at least one
organic or inorganic carrier material including agriculturally acceptable formulation
additives (C) such as surfactant, carrier, binder, disintegrate, pH adjuster, thickener,
preservative, anti-freezing agent, defoamers and/or coloring agent or a combination
thereof. The formulations may also contain, if desired, one or more surfactants and, if
desired, one or more further auxiliaries customary for crop protection compositions.
Suitable surfactants (a dispersant, a wetting agent, a spreader, an adjuvant for
penetration enhancement, rain fastness, soil leaching control etc.) are nonionic or
anionic or a combination of these surfactants. It is preferred to use more than two kinds
of surfactants, which have different chemical structure. Suitable surfactants are, for
10
example, sugar esters (such as sorbitan monolaurate, polyoxyethylene sorbitan
monolaurrate), polyoxyethylene alkyl ethers (such as polyoxyethylene lauryl ether or
polyoxyethylene coconut fatty alcohol ether), polyoxyethylene aryl ethers (such as
polyoxyethylene nonylphenyl ether or polyoxyethylene trystyrylphenyl ether),
polyoxyethylene vegetable oil ethers (such as polyoxyethylene castor oil),
polyoxyethylene fatty acid esters (such as polyoxyethylene monolaurate),
polyoxyethylene polyoxypropylene block co-polymers, polyoxyethylene
polyoxypropylene alkyl ether (such as polyoxyethylene polyoxypropylene lauryl ether),
polyoxyethylene alkyl amines (such as polyoxyethylene stearyl fatty amine), alkyl
sulfates (such as sodium lauryl sulfate), polyoxyethylene alkyl ether sulfates (such as
sodium polyoxyethylene lauryl ether sulfate), polyoxyethylene aryl ether sulfates (such
as sodium polyoxyethylene nonylphenyl ether sulfate or ammonium polyoxyethylene
tristyrylphenyl ether sulfate), alkane sulfonates (such as sodium dodecyl sulfonate),
‘alpha’-olefin sulfonate, aryl sulfonates (such as sodium dodecylbenzene sulfonate,
sodium naphthalenesulfonate, sodium alkylnaphthalene sulfonate, sodium naphthalene
sulfonate formaldehyde condensate or sodium alkyl diphenyl ether sulfonate),
alkylsulfosuccinates (such as sodium dioctylsulfosuccinate), sodium lignosulfonates,
polyoxyethylene alkyl ether phosphate, polyoxyethylene aryl ether phosphates (such as
polyoxyethylene phenyl ether phosphate) and polyoxyethylene polyoxypropylene block
co-polymer phosphate or a combination thereof.
Suitable liquid carriers are, for example, water, alcohols (such as ethanol, propanol,
isopropanol ethylene glycol, diethylene glycol, propylene glycol, polyethylene glycol,
glycerin), polyol ether (such as ethylene glycol monopropyl ether, diethylene glycol
monomethyl ether), ketones (such as methyl isobutyl ketone, cyclohexanone), ethers
(such as dipropyl ether, dioxane, ethylene glycol monoethyl ether, tetrahydrofuran,
dipropylene glycol dimethyl ether), aliphatic hydrocarbons (such as normal paraffin,
naphthene, isoparaffin, kerosene, mineral oil), aromatic hydrocarbons (such as xylene,
solvent naphtha, alkyl naphthalene), esters (such as ethyl acetate, diisopropyl phthalate,
dimethyl adipate), lactones (such as gamma-butyrolactone), amides (such as
dimethylformamide, N-methylpyrrolidone, N,N-dimethyldecanamide), nitriles (such as
11
acetonitrile), sulfur compounds (such as dimethyl sulfoxide) and vegetable oils (such as
soybean oil, rapeseed oil, cotton seed oil). These liquid carriers may be used alone or in
a combination of two or more kinds.
Suitable solid carriers are, for example, natural minerals (such as talc, kaolinite,
pyrophyllite, montmorillonite, attapulgite, bentonite, calcite, diatomaceous earth),
synthetic minerals (such as precipitated silica, fumed silica and calcium carbonate),
inorganic salts (such as calcium carbonate, ammonium sulfate, sodium sulfate,
potassium chloride) and organic materials (such as urea, lactose, starch, cellulose,
plant powders). These solid carriers may be used alone or in a combination of two or
more kinds.
Suitable binders are, for example, polyvinyl alcohol, dextrin, denatured dextrin, soluble
starch, carboxymethyl cellulose and bentonite or a combination thereof.
Suitable disintegrants are, for example, sodium tripolyphosphate, sodium
hexametaphosphate, carboxymethyl cellulose, sodium polycarbonate and bentonite or a
combination thereof.
Suitable pH adjusters are, for example, sodium or potassium carbonate, sodium or
potassium hydrogen carbonate, sodium or potassium dihydrogenphosphate, disodium
or dipotassium hydrogenphosphate, citric acid, malic acid and triethanolamine or a
combination thereof.
Suitable thickeners are, for example, xanthan gum, welan gum, guar gum, polyvinyl
alcohol, carboxymethyl cellulose and its salt, silica and bentonite or a combination
thereof.
Suitable preservatives are, for example, 4-hydroxybenzoic acid esters, 2-methyl-4-
isothiazolin-3-one, 5-chloro-2-methyl-4-isothiazolin-3-one and 1,2-benzisothiazolin-3-
one or a combination thereof.
12
Suitable anti-freezing agents are, for example, glycerin, ethylene glycol, propylene
glycol, diethylene glycol, dipropylene glycol and urea or a combination thereof.
Suitable defoamers are, for example, silicone compounds and organic fluorine
compounds or a combination thereof.
Suitable coloring agents are, for example, organic dyestuffs (such as azo dye,
phthalocyanine dye or alizarin dye) and inorganic pigments (such as iron oxide) or a
combination thereof.
The formulation may be in the form of a single package formulation for pre-mix
application containing both the pyrimidinyloxybenzoate (herbicide A) and the
aryloxyphenoxy-propionate (herbicide B) together with agriculturally acceptable
formulation additives for crop protection compositions. The formulation may be in the
form of a two package formulation, wherein one package contains a formulation
herbicide A while the other package contains a formulation of the herbicide B and
wherein both formulations contain agriculturally acceptable formulation additives for
crop protection compositions. In the case of two package formulations the formulation
containing herbicide A and the formulation containing the herbicide B are mixed prior to
application.
In the formulation of the present invention the active ingredients, i.e. herbicide A,
herbicide B and optional further additives are formed to several types of formulations
such as not being limited to, emulsifiable concentrate (EC), wettable powder (WP),
water dispersible granules (WG), suspension concentrate (SC), suspo-emulsion (SE)
etc.
In one embodiment of the present invention, the composition of the wettable powder
formulation is provided. The composition of wettable powder comprises
pyrimidinyloxybenzoate and aryloxyphenoxy-propionate as active ingredients, surfactant
13
and carrier. Other formulation additives such as pH adjuster and colorant may be
additionally used.
A method for preparing the wettable powder formulation of the present invention is also
provided. The wettable powder formulation can be prepared by mixing the active
ingredients, surfactant and carrier. Usually active ingredients, surfactant, carrier and
other formulation additives are mixed uniformly in a mixer and milled by a mill such as
an air jet mill to median diameter 5 to 50 micrometer.
In another embodiment of the present invention, the composition of the water
dispersible granule formulation is provided. The composition of water dispersible
granule comprises pyrimidinyloxybenzoate and aryloxyphenoxy-propionate as active
ingredients, surfactant, binder, disintegrant and carrier. Other formulation additives such
as pH adjuster and colorant may be additionally used.
A method for preparing the water dispersible granule formulation of the present
invention is also provided. The water dispersible granule formulation can be prepared
by mixing the active ingredients, surfactant, binder, disintegrant and carrier. Usually the
active ingredients, surfactant, binder, disintegrant, carrier and other formulation
additives are mixed uniformly in a mixer and milled by a mill such as an air jet mill to
median diameter 5 to 50 micrometer. The milled mixture is kneaded by adding 2 to
10 % of water, extruded and dried. Other granulation method such as spray dry or
fluidized bed granulation may be used. In this case, the milled mixture is well mixed with
enough amount of water to get slurry.
In yet another embodiment of the present invention, the composition of the suspension
concentrate formulation is provided. The composition of suspension concentrate
comprises pyrimidinyloxybenzoate and aryloxyphenoxy-propionate as active ingredients,
surfactant, thickener, preservative, anti-freezing agent and water. Other formulation
additives such as defoamer, pH adjuster and colorant may be additionally used.
14
A method for preparing the suspension concentrate formulation of the present invention
is also provided. The suspension concentrate formulation can be prepared by wet
milling of the active ingredients mixed with surfactant, water and other formulation
additives. Usually the active ingredients, surfactant and anti-freezing agent are mixed by
dissolving or dispersing in water. The mixture is preliminary milled by a homogenizer
such as a colloid mill and then milled by a bead mill till median diameter reaches to 1 to
10 micrometer. Defoamer may be used during milling. After the milling, aqueous
solution of thickener containing preservative is added.
Example 1: Water dispersible granule (WG)
Composition of Bispyribac sodium 20.0% Fenoxaprop-p-ethyl 45.6 % WG
Bispyribac sodium technical 20.0 w/w% (as a.i.)
Fenoxaprop-p-ethyl technical 45.6 (as a.i.)
Sodium lignosulfonate 4.0
Sodium naphthalenesulfonate 2.0
Sodium dioctylsulfosuccinate 2.0
Carboxymethyl cellulose 1.0
Kaolin clay 25.4 (Balance)
Total 100.0 w/w%
Example 2: Suspension concentrate (SC)
Composition of Bispyribac sodium 12.5% Fenoxaprop-p-ethyl 28.5 % SC
Bispyribac sodium technical 12.5 w/v% (as a.i.)
Fenoxaprop-p-ethyl technical 28.5 (as a.i.)
Polyoxyethylene polyoxypropylene alkyl ether 10.0
Sodium naphthalenesulfonate
formaldehyde condensate 2.0
Polyoxyethylene trystyrylphenyl ether 2.0
15
Sodium dioctylsulfosuccinate 1.5
4-hydroxybenzoic acid esters 0.1
Xanthan gum 2% aqueous solution 1.9
Propylene glycol 5.0
Water 36.5 (Balance)
Total 100.0 w/v%
The compositions or formulation according to the present invention are effective in the
post-emergence control of numerous monocotyledonous and dicotyledonous weeds.
The composition or formulation according to the present invention has no phytotoxicity
with respect to important agricultural crops. This results in the present invention being
effective and selective in the management and control of weeds.
At other occasions, the composition or formulation of the present invention can also be
used for total control of weeds, in relation to the quantity of active principles adopted.
For practical use in agriculture, the composition or formulation of the present invention
can be applied in such quantities as to guarantee applicative dosages of the synergistic
mixture.
In order to widen the action range of compositions or formulation of the present
invention comprising a pyrimidinyloxybenzoate and an aryloxyphenoxy-propionate it is
envisaged in this invention to add other ingredients such as other herbicides, antidotes,
fungicides, insecticides, fertilizers, etc.
The present invention comprising a pyrimidinyloxybenzoate and an aryloxyphenoxypropionate
can be applied to weeds or their locus by the use of sprayers known to those
skilled in the art.
16
The term herbicide is used herein to mean an active ingredient that kills controls or
otherwise adversely modifies the growth of plants. An herbicidal 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, weeds and vegetation include
germinant seeds, emerging seedlings, plants emerging from vegetative propagules and
established vegetation.
Thus, from the foregoing description, it will be apparent to one of ordinary skill in the art that
many changes and modifications can be made thereto without departing from the spirit or
scope of the invention as set forth in the claims. Accordingly, it is not intended that the
scope of the foregoing description be limited to the description set forth above, but rather
that such description be construed as encompassing such features that reside in the present
invention, including all the features and embodiments that would be treated as equivalents
thereof by those skilled in the relevant art.
Following test results illustrate the present invention and not intended to limit the present
invention.
Effect of Bispyribac sodium 12.5 % + Fenoxaprop-p-ethyl 28.5 % SC on the weed flora of rice
Field Study:
Two field experiments were conducted in direct seeded and transplanted rice at Hansi
village of Hissar district in Haryana and at Barabanki village of Lucknow district in Uttar
Pradesh respectively, during kharif 2016’ to evaluate the efficacy Bispyribac sodium and
Fenoxaprop - p - ethyl and its combination, along with Pyrazosulfuron and Azimsulfuron
and other combination having Metsulfuron methyl and Chlorimuron ethyl, which were
used for comparison in rice. The experiments were carried out with variety Pusa 1121
plots having 5m x 4m size in randomized block design with 7 treatments and replicated
thrice. Post-emergence herbicide application was done around 20 days after sowing.
The target weeds of rice viz., Echinochloa colonum, Leptochloa chinensis, Cyperus
17
difformis, Eclipta alba and Sphenoclea zeylanica were counted to determine the efficacy
of the products. Bio-efficacy, in terms of species wise weed count, total weed count and
total dry weed weight were taken up.
Validations for Inventions Concepts:
The above mentioned field studies were undertaken with the following objectives.
 To determine the effective dose of herbicides combination on the weed flora of
Rice.
 To establish the synergistic action in terms of increased efficacy and broader
weed spectrum over solo application of both herbicides.
 Compatibility of the formulations in terms of physical appearance of mixture
solution, safety to crop plants, spray operator etc.
A. Effective Dose:-
Two trials were conducted to observe the efficacy of different herbicides against
major weeds of rice. Major weeds were Echinochloa colonum, Leptochloa chinensis,
Cyperus difformis, Eclipta alba and Sphenoclea zeylanica. Bio-efficacy, in terms of
species wise weed count, total weed count and total dry weed weight are presented in
Table -1.1 and Table 2.1.
It is revealed from tables that the best treatment was ready mix combination of
Bispyribac sodium 12.5% + Fenoxaprop ethyl 28.5% SC @ 82g a.i./ha. This ready mix
combination of Bispyribac sodium 12.5% + Fenoxaprop ethyl 28.5% SC @ 82 g a.i./ha
gave good efficacy on grasses, sedges and broad leaf weeds as compared to solo
applications of Bispyribac sodium 10% SC @ 25 g a.i/ha; Fenoxaprop ethyl 6.9% SC @
57 g a.i./ha; Pyrazosulfuron 10% WP @ 15 g a.i./ha; and Azimsulfuron 50% DF@ 35 g
a.i./ha and combination product of Metsulfuron methyl 10% and Chlorimuron ethyl 10%
WP @ 4 g a.i./ha.
Least total weed count of (2.3/m2 and 3.0/ m2) respectively at both locations was
observed with Bispyribac sodium 12.5% + Fenoxaprop ethyl 28.5% SC @ 82g a.i./ha as
18
compared to all other treatment including control having a total weed count of (28.3 and
31.33/m2) respectively at both locations.
B. Establishment of synergistic action:
Extensive literatures survey and more number of trials revealed that the
herbicide of different groups will have synergistic effect than additive or deleterious
effect. Based on the literature available, combinations of herbicides have been
developed and globally used on to combat on many weeds. Such combinations also
provides enhanced spectrum of activity and avoid resistance development for longer
period.
Present study also provides evidence on the synergistic effect of combination of
Bispyribac sodium 12.5 % + Fenoxaprop-p- ethyl 28.5 % SC @ 82g a.i./ha showing
effective control on grasses, sedges and broad leaf weeds as compared to solo
application of both molecules.
C. Compatibility of combination:-
Physical observation on the treated plants involving either solo products or the
combination does not affect the safety of the crop plants and provided the normal yield.
It has been observed that no detrimental effect on the skin and eyes irritation to the
spray operators either by combination or solo products (Table -1.3 & 2.3)
D. Yield:-
Yield data was also recorded and presented in Table-1.2 and Table-2.2. Highest
yield was recorded in the combination involving Bispyribac sodium 12.5 % +
Fenoxaprop-p- ethyl 28.5 % SC @ 82 g a.i/ha which provided a yield of 34.4 q/ha and
35.6 q/ha at both trial locations respectively. In the control, lowest yield was recorded
(28.7 q/ha and 31.3 q/ha) at both the location respectively. It is evident from the table
that the combination developed for the control of weeds of rice gave good control on
weeds and thereby increased the yield. Advantages to the end user customers for
19
parameters like broaden the spectrum of activity for the control of grasses, sedges and
broad leaf weeds.
Location: - 1
Location Name : Hansi, Haryana
Crop and Variety : Rice; Pusa -1121
Season : Kharif, 2016
Method of sowing : Direct seeded rice
Date of sowing : 20/5/2016
Date of application (POE) : 10/06/2016 (21 DAS)
Treatment detail: -
Sr.
No. Treatment
Time of
application
Dose/ha Dilution
in
g a.i./ha Water/ha
Formulatio
n
(g or ml)
T1 Bispyribac Sodium 10% SC POE 25 250 500 L
T2 Fenoxaprop- p- ethyl 6.9 % EC POE 57 825 500 L
T3 Bispyribac sodium 12.5 % +
Fenoxaprop-p- ethyl 28.5 % SC
POE 82 200 500 L
T4 Metsulfuron methyl 10% +
Chlorimuron ethyl 10 % WP
POE 4 20 500 L
T5 Pyrazosulfuron 10 % WP POE 15 150 500 L
T6 Azimsulfuron 50 % DF POE 35 70 500 L
T7 Control - - - -
*POE- Post Emergence
20
Results: -
Table-1.1: - Bio-efficacy of different treatments on the weed flora of Rice.
Sr.n
o. Treatment
Dose/ha Species wise Mean weed count/ M2 (Avg. of 3 replication) 45
DAA Total
weed
count /
m2
Total
weed dry
weight (g/
m2)
g
a.i./ha
g or
ml
Echinochlo
a colonum
Leptochlo
a
chinensis
Cyperus
difformis
Eclipta
alba
Sphenoclea
zeylanica
1 Bispyribac Sodium 10%
SC 25 250 0.3 (0.9) 5.0 (2.3) 0.3 (0.9) 0.7 (1.1) 0.3 (0.9) 6.7 (2.7) 0.8 (1.1)
2 Fenoxaprop-p-ethyl 6.9 %
EC 57 825 5.0 (2.3) 0.7 (1.1) 6.0 (2.5) 3.3 (2.0) 3.7 (2.0) 18.7
(4.4) 2.3 (1.7)
3
Bispyribac sodium 12.5 %
+ Fenoxaprop-p- ethyl 28.5
% SC
82 200 0.0 (0.7) 0.3 (0.9) 0.3 (0.9) 0.7 (1.1) 1.0 (1.2) 2.3 (1.6) 0.3 (0.9)
4 Metsulfuron methyl 10% +
Chlorimuron ethyl 10 % WP 4 20 8.3 (3.0) 5.3 (2.4) 1.3 (1.3) 0.0 (0.7) 0.0 (0.7) 15.0
(3.9) 1.9 (1.5)
5 Pyrazosulfuron 10 % WP 15 150 7.0 (2.7) 4.7 (2.3) 0.0 (0.7) 1.7 (1.5) 2.0 (1.6) 15.3
(4.0) 1.9 (1.6)
6 Azimsulfuron 50 % DF 35 70 4.3 (2.2) 4.7 (2.3) 0.3 (0.9) 3.7 (2.0) 4.0 (2.1) 17.0
(4.2) 2.1 (1.6)
7 Control - - 8.7 (3.0) 5.3 (2.4) 6.7 (2.7) 3.7 (2.0) 4.0 (2.1) 28.3
(5.4) 3.5 (2.0)
CD (0.05%) 0.348 0.379 0.304 0.286 0.354 0.531 0.138
DAA- Days after application Figures in parenthesis are square root value
21
Table -1.2: - Impact of different treatments on yield.
Sr.
no. Treatment Time of
application
Doses/ha Yield data
g a.i. Formulat
ion g or
ml
q/ha
1 Bispyribac Sodium 10% SC POE 25 250 32.1 (5.7)
2 Fenoxaprop-p-ethyl 6.9 % EC POE 57 825 30.1 (5.5)
3 Bispyribac sodium 12.5 % + Fenoxaprop-p-ethyl 28.5
% SC POE 82 200 34.4 (5.9)
4 Metsulfuron methyl 10% + Chlorimuron ethyl 10 % WP POE 4 20 29.5 (5.5)
5 Pyrazosulfuron 10 % WP POE 15 150 30.7 (5.6)
6 Azimsulfuron 50 % DF POE 35 70 31.4 (5.7)
7 Control - - 28.7 (5.4)
CD (0.05 %) 0.053
*POE- Post –Emergence Figures in parenthesis are square root value
22
Table – 1.3 Impact of different treatments on crop health of rice.
*POE – Post emergence; DAS – Days after spray
Sr.
No. Treatment Typ
e
Doses/ha
Phytotoxicity (0-10 scale) in terms of
yellowing, necrosis, wilting, epinasty,
hyponasty etc.
g
a.i./h
a
g or
ml
1
DAS
3
DAS
5
7DAS
7
DAS
10
DAS
1. Bispyribac Sodium 10% SC PO
E 25 250 0 0 0 0 0
2. Fenoxaprop 6.9 % w/v EC PO
E 57 825 0 0 0 0 0
3. Bispyribac sodium 12.5 % + Fenoxaprop-p-ethyl 28.5
% SC
PO
E 82 200 0 0 0 0 0
4. Metsulfuron methyl 10% + Chlorimuron ethyl 10 % WP PO
E 4 20 0 0 0 0 0
5. Pyrazosulfuron 10 % WP PO
E 15 150 0 0 0 0 0
6. Azimsulfuron 50 % DF PO
E 35 70 0 0 0 0 0
7. Control - - 0 0 0 0 0
23
Location: - 2
Location Name : Barabanki, Uttar pradesh
Crop : Rice
Variety : Pusa-1121
Method of sowing : Transplanted
Date of Transplanting : 18/6/2015
Date of application (POE) : 08/07/2015 (20 DAT)
Treatment detail: -
Sr.
No. Treatment
Time of
application
Dose/ha Dilution
in
g a.i./ha Water/ha
Formulatio
n
(g or ml)
T1 Bispyribac Sodium 10% SC POE 25 250 500 L
T2 Fenoxaprop 6.9 % w/v EC POE 57 825 500 L
T3 Bispyribac sodium 12.5 % +
Fenoxaprop-p- ethyl 28.5 % SC
POE 82 200 500 L
T4 Metsulfuron methyl 10% +
Chlorimuron ethyl 10 % WP
POE 4 20 500 L
T5 Pyrazosulfuron 10 % WP POE 15 150 500 L
T6 Azimsulfuron 50 % DF POE 35 70 500 L
T7 Control - -
*POE – Post-Emergence
24
Result:-
Table-2.1: - Bio-efficacy of different treatments on the weed flora of rice.
Sr.
no. Treatment
Doses/ha Species wise Mean weed count/ M2 (Avg. of 3
replication) 45 DAA
Total weed
count / m2
Total weed
dry weight
g (g/ m2)
a.i./ha g or ml Echinochlo
a colonum Dactylocteniu
m aegyptium
Cyperu
s
difform
is
Sphenocle
a zeylanica
1 Bispyribac Sodium 10% SC 25 250 0.7 (1.1) 13.0 (3.7) 0.7
(1.1) 0.7 (1.0) 15.0 (3.9) 1.88 (1.5)
2 Fenoxaprop-p-ethyl 6.9 %
w/v EC 57 825 5.7 (2.5) 1.7 (1.5) 4.7
(2.3) 4.0 (2.1) 16.0 (4.1) 2.00 (1.6)
3
Bispyribac sodium 12.5 %
+ Fenoxaprop-p-ethyl 28.5
% SC
82 200 0.3 (0.9) 0.7 (1.1) 0.7
(1.1) 1.3 (1.3) 3.0 (1.8) 0.38 (0.9)
4 Metsulfuron methyl 10% +
Chlorimuron ethyl 10 % WP 4 20 8.3 (3.0) 13.7 (3.8) 0.7
(1.1) 0.3 (0.9) 23.0 (4.8) 2.88 (1.8)
5 Pyrazosulfuron 10 % WP 15 150 7.7 (2.9) 14.3 (3.9) 2.3
(1.7) 2.3 (1.7) 26.67 (5.2) 3.33 (2.0)
6 Azimsulfuron 50 % DF 35 70 7.0 (2.7) 12.3 (3.6) 0.0
(0.7) 4.3 (2.2) 23.67 (4.9) 2.96 (1.9)
7 Control 8.0 (2.9) 14.0 (3.8) 5.0
(2.3) 4.3 (2.2) 31.33 (5.6) 3.92 (2.1)
CD (0.05%) 0.367 0.228 0.305 0.373 0.410 0.101
DAA – Days after application Figures in parenthesis are square root value
25
Table -2.2: - Impact of different treatments on yield.
Sr.
no.
Treatment Time of
application
Doses/ha Yield data
g a.i./ha g or ml q/ha
1 Bispyribac Sodium 10% SC POE* 25 250 33.4 (5.8)
2 Fenoxaprop 6.9 % EC POE 57 825 33.5 (5.8)
3 Bispyribac sodium 12.5 % + Fenoxaprop-p-ethyl 28.5 %
SC
POE 82 200 35.6 (6.0)
4 Metsulfuron methyl 10% + Chlorimuron ethyl 10 % WP POE 4 20 31.6 (5.7)
5 Pyrazosulfuron 10 % WP POE 15 150 31.5 (5.7)
6 Azimsulfuron 50 % DF POE 35 70 32.7 (5.8)
7 Control 31.3 (5.6)
CD (0.05 %) 0.0.33
*POE – Post Emergence Figures in parenthesis are square root value
26
Table – 2.3 Impact of different treatments on crop heath of rice.
*POE- Post Emergence; DAS – Days after spray
Sr.
No. Treatment Typ
e
Doses/ha
Phytotoxicity (0-10 scale) in terms of
yellowing, necrosis, wilting, epinasty,
hyponasty etc.
g a.i./ha g or ml 1
DAS
3
DAS
5
7DAS
7
DAS
10
DAS
1. Bispyribac Sodium 10% SC POE
* 25 250 0 0 0 0 0
2. Fenoxaprop-p-ethyl 6.9 % EC POE 57 825 0 0 0 0 0
3. Bispyribac sodium 12.5 % +Fenoxaprop-p- ethyl 28.5
% SC POE 82 200 0 0 0 0 0
4. Metsulfuron methyl 10% + Chlorimuron ethyl 10 % WP POE 4 20 0 0 0 0 0
5. Pyrazosulfuron 10 % WP POE 15 150 0 0 0 0 0
6. Azimsulfuron 50 % DF POE 35 70 0 0 0 0 0
7. Control 0 0 0 0 0

WE CLAIM:
1. A stable synergistic agrochemical composition for management of weed
flora in rice comprising a pyrimidinyloxybenzoate (A) and an
aryloxyphenoxy-propionate (B) and agriculturally acceptable 5 formulation
additives (C) wherein the weight percentage of (A) is 3 to 29%, weight
percentage of (B) is 7 to 66% and weight percentage of (C) is 5 to 90%.
2. A stable synergistic agrochemical composition for management of weed
10 flora in rice comprising a pyrimidinyloxybenzoate (A) and an
aryloxyphenoxy-propionate (B) and agriculturally acceptable formulation
additives (C) wherein the weight percentage of (A) is 3 to 15%, weight
percentage of (B) is 7 to 35% and weight percentage of (C) is 10 to 50% .
15 3. The composition as claimed in claims 1 and 2, wherein (A) is sodium 2,6-
bis[(4,6-dimethoxy-2-pyrimidinyl)oxy]benzoate and (B) is ethyl
(2R)2[
4[(
6chloro1,
3benzoxazol2yl)
oxy]phenoxy] propanoate.
4. The composition as claimed in claims 1 and 2, wherein (C) is selected from
20 at least one organic or inorganic carrier material including agriculturally
acceptable formulation additives such as surfactant, solid carrier, liquid
carrier, binder, disintegrate, pH adjuster, thickener, preservative, antifreezing
agent, defoamers and coloring agent, or a combination thereof
25 5. The composition as claimed in claim 4, wherein suitable surfactants
includes sugar esters (such as sorbitan monolaurate, polyoxyethylene
sorbitan monolaurrate), polyoxyethylene alkyl ethers (such as
polyoxyethylene lauryl ether or polyoxyethylene coconut fatty alcohol ether),
polyoxyethylene aryl ethers (such as polyoxyethylene nonylphenyl ether or
30 polyoxyethylene trystyrylphenyl ether), polyoxyethylene vegetable oil ethers
(such as polyoxyethylene castor oil), polyoxyethylene fatty acid esters
(such as polyoxyethylene monolaurate), polyoxyethylene polyoxypropylene
block co-polymers, polyoxyethylene polyoxypropylene alkyl ether (such as
28
polyoxyethylene polyoxypropylene lauryl ether), polyoxyethylene alkyl
amines (such as polyoxyethylene stearyl fatty amine), alkyl sulfates (such
as sodium lauryl sulfate), polyoxyethylene alkyl ether sulfates (such as
sodium polyoxyethylene lauryl ether sulfate), polyoxyethylene aryl ether
sulfates (such as sodium polyoxyethylene nonylphenyl 5 ether sulfate or
ammonium polyoxyethylene tristyrylphenyl ether sulfate), alkane sulfonates
(such as sodium dodecyl sulfonate), ‘alpha’-olefin sulfonate, aryl sulfonates
(such as sodium dodecylbenzene sulfonate, sodium naphthalene sulfonate
sodium alkylnaphthalene sulfonate, sodium naphthalene sulfonate
10 formaldehyde condensate or sodium alkyl diphenyl ether sulfonate),
alkylsulfosuccinates (such as sodium dioctylsulfosuccinate), sodium
lignosulfonates polyoxyethylene alkyl ether phosphate, polyoxyethylene
aryl ether phosphates (such as polyoxyethylene phenyl ether phosphate)
and polyoxyethylene polyoxypropylene block co-polymer phosphate.
15
6. The composition as claimed in claim 4, wherein the suitable liquid carriers
includes water, alcohols (such as ethanol, propanol, isopropanol ethylene
glycol, diethylene glycol, propylene glycol, polyethylene glycol, glycerin),
polyol ether (such as ethylene glycol monopropyl ether, diethylene glycol
20 monomethyl ether), ketones (such as methyl isobutyl ketone,
cyclohexanone), ethers (such as dipropyl ether, dioxane, ethylene glycol
monoethyl ether, tetrahydrofuran, dipropylene glycol dimethyl ether),
aliphatic hydrocarbons (such as normal paraffin, naphthene, isoparaffin,
kerosene, mineral oil), aromatic hydrocarbons (such as xylene, solvent
25 naphtha, alkyl naphthalene), esters (such as ethyl acetate, diisopropyl
phthalate, dimethyl adipate), lactones (such as gamma-butyrolactone),
amides (such as dimethylformamide, N-methylpyrrolidone, N,Ndimethyldecanamide),
nitriles (such as acetonitrile), sulfur compounds
(such as dimethyl sulfoxide) and vegetable oils (such as soybean oil,
30 rapeseed oil, cotton seed oil), or a combination thereof.
7. The composition as claimed in claim 4, wherein suitable solid carriers
includes natural minerals (such as talc, kaolinite, kaolin clay, pyrophyllite,
29
montmorillonite, attapulgite, bentonite, calcite, diatomaceous earth),
synthetic minerals (such as precipitated silica, fumed silica and calcium
carbonate), inorganic salts (such as calcium carbonate, ammonium sulfate,
sodium sulfate, potassium chloride) and organic materials (such as urea,
lactose, starch, cellulose, plant powders) , or a 5 combination thereof.
8. The composition as claimed in claim 4, wherein suitable binders includes
polyvinyl alcohol, dextrin, denatured dextrin, soluble starch, carboxymethyl
cellulose and bentonite, or a combination thereof.
10
9. The composition as claimed in claim 4, wherein suitable disintegrants
includes sodium tripolyphosphate, sodium hexametaphosphate,
carboxymethyl cellulose, sodium polycarbonate and bentonite, or a
combination thereof.
15
10. The composition as claimed in claim 4, wherein suitable pH adjusters
includes sodium or potassium carbonate, sodium or potassium hydrogen
carbonate, sodium or potassium dihydrogenphosphate, disodium or
dipotassium hydrogenphosphate, citric acid, malic acid and triethanolamine,
20 or a combination thereof.
11. The composition as claimed in claim 4, wherein suitable thickeners
includes xanthan gum, welan gum, guar gum, polyvinyl alcohol,
carboxymethyl cellulose and its salt, silica and bentonite, or a combination
25 thereof.
12. The composition as claimed in claim 4, wherein suitable preservatives
includes 4-hydroxybenzoic acid esters, 2-methyl-4-isothiazolin-3-one, 5-
chloro-2-methyl-4-isothiazolin-3-one and 1,2-benzisothiazolin-3-one, or
30 combination thereof.
30
13. The composition as claimed in claim 4, wherein suitable anti-freezing
agents includes glycerin, ethylene glycol, propylene glycol, diethylene
glycol, dipropylene glycol and urea, or combination thereof.
14. The composition as claimed in claim 4, wherein 5 suitable defoamers
includes silicone compounds and organic fluorine compounds, or
combination thereof.
15. The composition as claimed in claim 4, wherein suitable coloring agents
10 includes organic dyestuffs (such as azo dye, phthalocyanine dye or alizarin
dye) and inorganic pigments (such as iron oxide), or combination thereof.
16. A method for the preparation of a stable synergistic agrochemical
composition as claimed in claim 1 to 15, comprising comprising a
15 pyrimidinyloxybenzoate (A) and an aryloxyphenoxy-propionate (B) and
agriculturally acceptable formulation additives (C).