FIELD OF THE INVENTION
The present invention relates to a storage stable herbicidal composition, more
particularly to a dry flowable (DF) herbicidal composition comprising an
aryloxyphenoxypropionate herbicide and a process for preparing such dry
flowable (DF) herbicidal composition.
BACKGROUND OF THE INVENTION
Crop protection technology which includes all types of pesticides such as
herbicides, insecticides, fungicides, as well as biotechnological products help
control the thousands of weed species, harmful insects and numerous plant
diseases that afflict crops. In the absence of these crop protection and pest control
technologies, food production would decline, many fruits and vegetables would be
in short supply, and the price of food would rise. Additionally, the production of
important fibers for clothing, such as cotton, would decrease as farmers would
lose their harvests and livelihoods to crop pests and diseases. Thus, crop
protection is very important to increase the production of agricultural products and
at the same time reduce their cost.
In recent years, with the development of commercial agriculture, chemical
pesticides consisting of insecticides, herbicides and fungicides are playing an
increasingly important role for enhancement of food production from the
diminishing arable area to feed the burgeoning population in India. Weeds causes
serious losses in crops and vegetable production and affect the income of the
farmers and are known to threaten food security. Currently different herbicides
belonging to different chemical classes for eg., Aryloxyphenoxypropionate,
Cyclohexanedione, Phenylpyrazolin, Imidazolinone, Pyrimidinylthiobenzoic acid,
Sulfonylurea, Triazolopyrimidine etc. are used to control the weeds problem in
different crops.
Aryloxyphenoxypropionate herbicides are a class of compounds which are known
to be suitable for various herbicidal purposes. These include for example,
herbicides such as clodinafop-propargyl, cyhalofop-butyl, diclofop, diclofop-
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methyl, fenoxaprop-P-ethyl, fluazifop, fluazifop-butyl, fluazifop-P-butyl,
haloxyfop, haloxyfop-etotyl, haloxyfop-P-methyl, propaquizafop, quizalofop,
quizalofop-ethyl, quizalofop-P, quizalofop-P-ethyl and quizalofop-P-tefuryl, each
of which are known e.g. from the Pesticide Manual 171
h edition (British Crop
Protection Council), 2015; cf. EP 0083556, US 4713109, US 4894085, US
4897481, EP 302203, DE 2136828, DE 2223894, EP 0635996, GB 1599121, EP
52798, US 4545807 and GB 2042539.
The term "aryloxyphenoxypropionate herbicide" is generally used to describe
herbicides from the class of fatty acid synthesis inhibitors, in particular inhibitors
of the enzyme acetyl CoA carboxylase (ACCase) in plants, and which also has the
structural feature of a phenoxypropionate substituted in the phenyl ring by a
phenoxy group or functionally similar aryloxy or heteroaryloxy groups. An
alternative expression is "(hetero) aryloxyphenoxyproptionate herbicide",
including esters and salts of the basic acids. Preferred are the acids, salts thereof
and esters thereof, such as (C1-C8)alkyl esters, substituted (C1-C8)alkylesters, (C2-
Cg)alkenyl esters or (C2-Cg)alkynyl esters, in particular (C1-C4)alkyl esters, (C1-
C4)alkylesters which are substituted by one or more radicals selected from the
group consisting of halogen and (C1-C4)alkoxy, or (C2-C4)alkenyl esters or (C2-
C4)alkynyl esters.
Herbicidally active compounds of the aryloxyphenoxypropionate type are
generally used post-emergence for controlling grass weeds particularly in cereals
such as rice, wheat and barley, or in a variety of broad-leaved crops such as oil
seeds, and can be employed at relatively low application rates. However, these
compounds are not always fully compatible with some important crop plants and
in some cases the injury to crop plants at herbicide application rates needed to
control weed growth renders the herbicide unsuitable for control of a broad range
of weed species in the presence of certain crops. Reduction in herbicidal injury to
crops without an unacceptable reduction in the herbicidal action can be
accomplished by use of crop protectants known as "safeners". It is known that
herbicidally active compounds of the aryloxyphenoxypropionate type may be used
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in combination with a safener, for example as described in European patent EP
0635996 and United States Patent US 5700758, which disclose that the phytotoxic
effects of herbicides including aryloxyphenoxypropionates may be safened using
4,5-pyrazoline-3-carboxylic ester derivatives, and in particular the combination
with fenoxaprop-P-ethyl is described.
Fenoxaprop-P-ethyl is a systemic grass herbicide used for control of annual
grasses @ 50-120 gm a.i./ha. Fenoxaprop-P-ethyl [ethyl (R)-2-[4-(6-chloro-1,3-
benzoxazol-2-yloxy)phenoxy]propionate] is a herbicidally active R-enantiomer of
the racemic substance fenoxaprop-ethyl. Herbicides from the fenoxaprop-ethyl
group of fenoxaprop ester are known from numerous documents. Thus, for
example, the herbicidal action of numerous such compounds is described in U.S.
Pat. Nos. 6,908,883 B2 and 6,887,827 B2. Fenoxaprop-P-ethyl is preferably used
together with the safener diethyl (RS)-1-(2,4-dichlorophenyl)-5-methyl-2-
pyrazoline-3,5-dicarboxylate, which is known by the name mefenpyr diethyl. Both
compounds are commercially available in the form of an emulsifiable concentrate
(EC). Some of the prior arts in this field are discussed below.
European Patent No. EP 1555876 B2 describes a method for prepanng a
nanoparticle including a polymer-associated fenoxaprop-P-ethyl suspo-emulsion
(SE) comprising fenoxaprop-P-ethyl, safener, solvent, emulsifier and the other
ingredients. The method described here is that, firstly fenoxaprop-P-ethyl, safener,
solvent and emulsifiers are mixed to make a oil phase. Parallelly, dispersing cum
wetting agent and other ingredients are mixed in water to get a homogeneous
mass. Secondly, fenoxaprop-P-ethyl oil phase is mixed with this homogeneous
mass along with a solution of binder in water to get a homogeneous mixture.
PCT publication WO 2013186695 AI relates to a solid pesticidal wettable powder
(WP) formulation containing nanoparticles including a polymer-associated
fenoxaprop-P-ethyl comprising fenoxaprop-P-ethyl, safener, polymer, copolymer,
wetting/dispersing agent and the other ingredients. The method
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described provides formulations wherein the average diameter of nanoparticles is
between about 1 nm and about 500 nm.
PCT publication WO 1993014631 A1 discloses water dispersible granules that are
prepared by first preparing absorbent water dispersible granules and then loading
biologically active substances into the preformed absorbent granules. This
publication particularly relates to active substance selected from the group
consisting of fluazifop-P-butyl, lambda-cyhalothrin and propargite.
United States Patent application US 13/664790 discloses a method of improving
the dispersion properties in water of a pesticide-containing granule which
comprises: providing a powder comprising a pesticide active ingredient; adding
water to the powder; blending the powder and the water into a mixture; and
processing the mixture into granules; wherein the improvement is characterized by
incorporating one or more water soluble agglomeration suppressants into the
powder or the water prior to blending. This prior art has drawback of improper
dispersion of granules in the spray solution.
PCT publication WO 2013127790 A2 relates to a method for prepanng an
emulsifiable granule comprising the steps of a) emulsifying water with a solution
of a pesticide in a water-insoluble solvent, b) contacting the emulsion resulting
from step a) and a solid dispersant containing a water soluble polycarboxylate and
a water-soluble anionic surfactant, and c) extruding the paste resulting from step
b). The invention further relates to emulsifiable granules containing a waterinsoluble
solvent, a pesticide, which is dissolved in the water-insoluble solvent, a
water-soluble polycarboxylate, and a water-soluble anionic surfactant. The
compositions disclosed in this prior art comprise organic solvents, which are
hazardous to the environment.
As stated above, both fenoxaprop-p-ethyl and mefenpyr diethyl are commonly
formulated as an emulsifiable concentrate (EC). However, an EC contains very
large amounts of organic and petroleum distillate solvents, and therefore carries a
risk of flammability during production, storage, packing, transportation and
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application. The use of these highly flammable solvents is harmful to humans and
non-target organisms as these organic solvents are rapidly absorbed into the skin
of humans and non target organisms. After application in agricultural fields, these
volatile solvents evaporate and contaminate the environment. Hence, research is
being focused towards better pesticide formulations which minimize the use of
organic solvents in agricultural and public health pest control applications.
Environment protection authorities are also encouraging newer pesticide
formulations with no or minimum use of solvents.
The only formulation of Fenoxaprop-P-ethyl being produced by pesticide
industries is an emulsifiable concentrate (EC) formulation, which has numerous
aforestated drawbacks. Moreover, the herbicidal activity of fenoxaprop-P-ethyl
formulated as EC is not always satisfactory or, with a satisfactory activity,
undesirable damage to the plants is observed even after the use of safener. Thus,
there is a need to provide an improved herbicidal formulation of fenoxaprop-Pethyl
which is not only highly effective in targeting weeds and safe to humans and
other warm-blooded animals but also solves the problems associated with existing
commercial formulations.
Therefore the major objectives of the present study are as follows:
The primary objective of the present invention is to provide a solid dry flowable
formulation of the herbicide Fenoxaprop-P-ethyl.
Another objective of the invention is to provide a solid dry flowable formulation
of Fenoxaprop-P-ethyl, which eliminates the problems faced in using its existing
solvent based EC formulation like flammability, sedimentation, inhalation risk,
skin toxicity and phytoxicity.
A further objective of the invention is to provide a process for the preparation of
dry flowable formulations of Fenoxaprop-P-ethyl with good physic-chemical
qualities, stability and desired bio-efficacy against target agricultural pests.
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SUMMARY OF THE INVENTION
The present invention discloses a dry flowable herbicidal composition,
comprising:
(a) fenoxaprop-p-ethyl;
(b) a safener; and
(c) at least one excipient selected from the group consisting of
wetting agent, dispersing agent, anti foaming agent, and filler.
In accordance with an embodiment, fenoxaprop-p-ethyl is present in an amount in
the range from 5 to 15% w/w. Preferably, fenoxaprop-p-ethyl is present in an
amount of9% w/w.
In accordance with another embodiment, the safener is present in an amount of
2.90% and selected from the group consisting of cloquintocet mexyl, isoxadifen
ethyl, and mefenpyr diethyl.
In accordance with yet another embodiment the safener is preferably mefenpyr
diethyl.
The wetting agent is present in an amount in the range from 2 to 4% and is sodium
disopropyl naphthalene sulfonate.
Further, the dispersing agent is present in an amount in the range from 8.00 to
14% w/w and is sodium polycarboxylate.
Still further, the anti foaming agent is present in an amount of 0.1 to 1% w/w and
is 1572 SAG (Polydimethy1 Si1oxane).
The filler present in the dry flowable herbicidal composition of the present
invention is china clay (kaolin).
The dry flowable herbicidal composition controls and prevents annual grassy and
monocot weeds. The dry flowable herbicidal composition also controls and
prevents crop weeds in cereals, pulses and oilseeds.
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The present invention further discloses a process for preparing the dry flowable
herbicidal composition, comprising the steps of:
(a) mixing all the excipients in a pre-blender to form a homogenous
mixture;
(b) adding fenoxaprop-p-ethyl and safener and grinding m an mr
classifying mill/jet mill at 2000 rpm;
(c) adding requisite quantity of water to make a dough and passing
through extruder mill maintained at a temperature of 50 ·c to
produce granules of desired dimensions;
(d) drying the granules obtained in step (c) in a dryer to obtain dried
granules; and
(e) sieving the dried granules obtained m step (d) to obtain dried
granules of desired dimensions.
The wetting time of the dry flowable is less than 60 seconds; the suspensibility of
the formulation is more than 80% and the final product is stable when subjected to
accelerated temperature storage at 54 oc for 14 days.
The dry flowable composition/formulation is free of any organic solvent.
DETAILED DESCRIPTION OF THE INVENTION
Discussed below are some representative embodiments of the present invention.
The invention in its broader aspects is not limited to the specific details and
representative methods. The illustrative examples are described in this section in
connection with the embodiments and methods provided. The invention according
to its various aspects is particularly pointed out and distinctly claimed in the
appended claims read in view of this specification and appropriate equivalents.
It is to be noted that, as used in the specification and the appended claims, the
singular forms "a", "an" and "the" include plural referents unless the context
clearly dictates otherwise. Thus, for example, reference to a composition
containing "a compound" includes a mixture of two or more compounds. It should
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also be noted that the tenn "or" is generally employed in its sense including
"and/or" unless the content clearly dictates otherwise.
The expression of various quantities in terms of "% w/w" or "%" means the
percentage by weight, relative to the weight of the total solution or composition
unless otherwise specified.
The present invention discloses a dry flowable herbicidal composition,
comprising:
(a) fenoxaprop-p-ethyl;
(b) a safener; and
(c) at least one excipient selected from the group consisting of
wetting agent, dispersing agent, anti foaming agent, and filler.
In accordance with an embodiment, fenoxaprop-p-ethyl is present in an amount in
the range from 5 to 15% w/w.
Herbicidally active compounds of the aryloxyphenoxypropionate type are
generally used post-emergence for controlling grass weeds and can be employed
at relatively low application rates. However, these compounds are not always fully
compatible with some important crop plants and in some cases the injury to crop
plants at herbicide application rates needed to control weed growth renders the
herbicide unsuitable for control of a broad range of weed species in the presence
of certain crops. Reduction in herbicidal injury to crops without an unacceptable
reduction in the herbicidal action can be accomplished by use of crop protectants
known as "safeners", also sometimes referred to as "antidotes" or "antagonists". It
is known that herbicidally active compounds of the aryloxyphenoxypropionate
type may be used in combination with a safener.
In accordance with an embodiment of the invention, the safener is present in an
amount of 2.90% and selected from the group consisting of cloquintocet mexyl,
isoxadifen ethyl, and mefenpyr diethyl. Preferably, the safener is mefenpyr
diethyl.
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The wetting agents increase the spreading and penetrating properties of a liquid on
and within the formulation by lowering its surface tension. Preferably, the wetting
agents are present in an amount in the range from 2 to 4%. The wetting agents of
the present disclosure are selected from the group consisting of sodium disopropyl
naphthalene sulfonate, sulfosuccinates, sulfated esters, alcohol sulfate,
naphthalene sulfonates, alkyl benzene sulfonates and combinations thereof.
The dispersing agent is used for uniformly dispersing the ingredients, especially
the active ingredients, throughout the dosage form. The dry flowable herbicidal
composition of the present invention comprises the dispersing agents in an amount
in the range from 8.00 to 14% w/w. The dispersing agents are selected from the
group consisting of polycarboxylates, naphthalene sulfonate formaldehyde
condensates, phenol sulfonate formadehyde condensates, sodium lignosulfonates,
calcium lignosulphates, methyl oleyl taurates, and sodium polycarboxylate.
The anti foaming agent prevents foaming of the formulation and is present in an
amount of 0.1 to 1% w/w. The anti foaming agent used in the present invention is
1572 SAG (Polydimethyl Siloxane).
Fillers provide the required bulk of the composition when the dosages of the
active components are inadequate to produce formulations of adequate weight and
size. The fillers used in the present invention is china clay (kaolin).
In accordance with another aspect, the dry flowable herbicidal composition is used
to control and prevent crop weeds in cereals, pulses and oil seeds. In one
exemplary embodiment, the dry flowable herbicidal composition is used to control
unwanted annual grasses in paddy, soyabean and pulse crops. In another
exemplary embodiment of the present invention, the dry flowable herbicidal
composition is used to control annual grasses such as Echinochloa spp and other
narrow leaved weeds. In yet another embodiment, the dry flowable herbicidal
composition is used to control and prevent annual grassy and monocot weeds.
In accordance with yet another aspect, the present disclosure provides a process
for the preparation of a dry flowable herbicidal composition. The process initially
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includes, mixing all the excipients in a pre-blender for one hour to form a
homogenous mixture. Thereafter, fenoxaprop-p-ethyl and mefenpyr diethyl are
added to the homogenous mixture and grinding is carried out in an air classifYing
mill/jet mill at 2000 rpm. After that, requisite quantity of water is added to make
dough, and the dough is quickly passed through an extruder mill maintained at a
temperature of 50 ·c to produce granules of desired dimensions. Further, the
granules are dried in a dryer to obtain dried granules. Finally, the dried granules
are sieved to obtain dried granules of desired dimensions.
The dry flowable herbicidal composition of the present invention dissolves
completely in water, enables faster and easier sprayer cleanout, and delivers more
consistent weed control.
EXAMPLES
The present invention is more particularly described in the following examples
that are intended as illustrations only, since numerous modifications and
variations within the scope of the present invention will be apparent to those
skilled in the art. The following examples illustrate the basic methodology and
versatility of the present invention.
Examples 1-3
The unit of each value below is "% w/w" i. e. the percentage by weight, relative to
the weight of the total solution or composition unless otherwise specified. The
compositions contemplated by each of the Examples 1-3 that are tabulated in
Table I are formulated as a dry flowable (DF) herbicidal composition.
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Table 1: Dry flowable herbicidal compositions
Component Function Examples
1 2 3
Fenoxaprop-p-ethyl **A.l. 5.00 9.00 15.00
Mefenpyr diethyl (Safener) **A.l. 2.90 2.90 2.90
Sodium Disopropyl Naphthalene
Wetting agent 4.00 2.00 2.00
Sulfonate
Sodium Polycarboxylate
Dispersing 8.00 10.00 14.00
agent
1572 SAG (Polydimethyl Siloxane)
Anti foaming 0.1 0.6 1.00
agent
China clay (Kaolin) Filler *q.s. *q.s. *q.s.
*q.s. = quantity sufficient
**A.!= Active ingredient
The aforestated herbicidal compositions can be formulated as a dry flowable (DF)
herbicidal composition by the process described herein below.
Process of preparation of dry flowable (DF) herbicidal composition
The herbicidal compositions of Examples 1-3 were prepared by the process
described hereinafter. Entries for fenoxaprop-p-ethyl and mefenpyr diethyl in
table 2 differ from those in table 1 as entries in table 1 are for 100% pure
compounds, whereas those in table 2 are for technical ones, i.e. compounds
containing a certain percentage of impurities.
Furthermore, the amounts of ingredients presented in table 2 may be greater than
the amounts calculated taking into account the percentage purity of the active
ingredients, to compensate for losses of said ingredients during the manufacturing
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process. It was observed that following said process on industrial scale the final
percentage of ingredients will be as illustrated in table 1.
All the raw materials were verified for conformance to the laid down individual
specifications. The required quantities of excipients as illustrated in Table 2
below, were weighed, and transferred to pre-blender and blended for one hour, to
form a homogeneous mixture. Thereafter, the homogenous mixture, fenoxapropp-
ethyl and mefenpyr diethyl were transferred to an air classifying mill/ jet mill
and ground for one hour at 2000 rpm. After that, requisite quantity of water was
added to make dough and the dough was quickly passed through an extruder mill
maintained at a temperature of 50 ·c to produce granules of desired dimensions.
This was followed by slow drying the granules in a dryer to obtain dried granules.
Finally, the dried granules were sieved to remove dust and maintain size of the
granules as per the desired dimensions. The quality of in-process sample was
checked for conformance to the specifications. The quality approved in-process
sample was transferred for packing as per the requirements.
Table 2: Raw materials required for the preparation of dry flowable
herbicidal composition
Component
Fenoxaprop-p-ethyl (97 .00%
w/w minmum purity)
Mefenpyr diethyl (95.00% w/w
minmum purity, Safener)
Sodium disopropyl
naphthalene sulfonate
Sodium polycarboxylate
1572 SAG (Polydimethyl
Function
Technical
Technical
Wetting agent
Dispersing
agent
Anti foaming
13
Examples
Quantities of materials
charged (kg)
1 2 3
5.16 9.28 15.47
3.10 3.10 3.10
4.00 2.00 2.00
8.00 10.00 14.00
0.1 0.60 1.00
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Siloxane) agent
China clay (Kaolin) Filler 79.64 75.02 64.43
Physical and Chemical Properties of the dry flowable (D F) herbicidal
composition of the present invention
The dry flowable (OF) herbicidal compositions prepared as per above process
were evaluated for different physical and chemical properties.
a) Disintegration time in water was analyzed as per method given in Indian
Standard (IS): 6940-1982 (Methods of test for pesticides and their
formulations (first revision)) Clause no. 11.4. Time taken to disintegrate in
normal water by all the samples was less than 50 seconds which shows
that the novel dry flowable (OF) herbicidal compositions ofFenoxaprop-pethyl
disintegrate quickly at the time of preparing the spray solution.
b) Wet Sieving test was conducted as per method given in Indian Standard
(IS): 6940-1982 (Methods of test for pesticides and their formulations
(first revision)) Clause no. 11.1. As per results, over 99.65% (by mass) of
all the samples of dry flowable (OF) herbicidal compositions of
fenoxaprop-p-ethyl pass through 45 f!m IS Sieve against minimum 99%
requirement, which shows the uniformity of particle size and better spray
suitability of the formulation.
c) Suspensibility analysis was conducted as per Clause no. 11.2, Indian
Standard (IS): 6940-1982 (Methods of test for pesticides and their
formulations (first revision)). Suspensibility of all the samples was more
than 78%, indicating that dry flowable (OF) herbicidal compositions of
fenoxaprop-p-ethyl will provide a stable spray suspension in water,
thereby ensuring homogeneous distribution of active ingredients on target
site in agricultural fields to achieve effective control of weeds.
d) The storage stability test at elevated temperature (accelerated) was
conducted as per method given in, International Collaborative
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International Pesticides Analytical Council (CIP AC) Hand book vide
number 46.1. The results show that all the samples of dry flowable (DF)
herbicidal compositions of fenoxaprop-p-ethyl were found to be stable
when subjected to accelerated temperature at 54 oc for 14 days, which is
equal to 30 month storage (For 2 years shelflife) at normal temperature.
Bio-efficacy of the dry flowable herbicidal composition comprising
fenoxaprop-p-ethyl
Field tests of the herbicidal compositions of the present invention were conducted
at various trial sites against annual grassy and narrow leaved weeds in paddy crop.
Paddy, one of the major staple crops in the world and India, provides almost 35%
of the calories to human being. The dry flowable (DF) herbicidal compositions of
the present invention comprising fenoxaprop-p-ethyl and commercially available
fenoxaprop-p-ethyl 9.3% EC formulation were evaluated against Echinochloa spp.
weeds. Effect on vigor/yield of the crop was also evaluated. The dry flowable
(DF) herbicidal compositions of the present invention were prepared by the
process described above. Commercially available fenoxaprop-p-ethyl 9.3% EC
was diluted with water to the stated concentration of the active compound.
Experiments were carried out in randomized blocks with four repetitions and each
plot measured an area of 100 sq. mts (10 x 10 mts). The formulations tested were
weighed according to doses and diluted in water and applied using high volume
knapsack sprayer fitted with a pressure regulator and a vertical bar with one flat
fan nozzle at 20 days after transplanting (DAT) at all the locations and evaluated
for% WCE in paddy. The number of different weed flora was assessed at 30 days
after application (DAA) and 45 DAA, their mean calculated and presented in table
4. The rate of application was 500 1/ha for all the trials.
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Weed control efficiency (WCE%) =
weed dry weight in untreated plot- weed dry weight in treated plot
----~--~----~~--~~~----~~~--------~--xlOO
weed dry weight in untreated plot
Details of Experiment
Target weeds: Echinochloa spp
Crop: Transplanted Paddy
The treatment details are tabulated in Table 3 below.
Table 3: Treatment details for evaluation of Bio-efficacy of herbicide
composition against Echinochloa spp in Paddy
Particular Treatment Dose Time of
/Acre Application
T1 Control (Water Spray) 20DAT
T2 Fenoxaprop-p-Ethyl9% DF 200g 20DAT
T3 Fenoxaprop-p-Ethyl 9% DF 250 g 20DAT
T4 Fenoxaprop-p-Ethyl 9% DF 300g 20DAT
Ts Fenoxaprop-p-Ethyl 9.3% EC 250m! 20DAT
T6 Hand Weeding@ 20 & 40 OAT
T1 Weed Free
The bio-efficacy of different treatments on paddy crop and the treatment wise
yield data of paddy are summarized in Tables 4-5 below.
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--~-- 4·-.T-- -- ~-~ --fl- ---- -.-f- d-i-ff-<- ----- ------------~ ~-- ------ ------d Padd
Treatments Dose/Acre Population of weeds Dry weight of weeds Per cent weed control WCE(%)
(Nos. m·2) (g m-2)
E. crussgalli E. colona E. crussgalli E. colona E. crussgalli E. colona E. crussgalli E. colona
T, -- 18.92 17.71 15.30 14.32
- - - -
( 4.41) (4.27) (3.97) (3.85)
Tz 200g 5.50 5.06 1.63 1.50 89.52 90.01 89.32 89.53
(2.45) (2.35) (1.46) (1.41)
T3 250 g 1.98 1.76 0.70 0.63 90.10 91.32 95.41 95.63
(1.57) (1.50) (1.10) (1.06)
T4 300 g 1.87 1.54 0.79 0.66 93.06 92.56 94.86 95.39
(1.54) (1.42) (1.13) (1.07)
Ts 250m! 4.51 4.07 1.94 1.72 76.02 77.07 87.38 87.92
(2.24) (2.13) (1.56) (1.49)
T6 -- 6.60 5.83 5.82 5.13 65.14 67.02 61.85 64.12
(2.66) (2.52) (2.51) (2.37)
~---
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T1 -- 0.00 0.00 0.00 0.00 100.00 100.00 100.00 100.00
(0.71) (0.71) (0.71) (0.71)
SEm (±) - 0.30 0.34 0.20 0.15 1.25 1.79 1.30 1.00
CD at5% - 0.89 1.00 0.60 0.44 3.68 5.29 3.84 2.95
. - . - -. . ~ ·g p g. ifi. (; >) befi 'Y·
SEm ±:Standard Errors of Means; CD 5%: Critical Difference.
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Table 5: Treatment Wise Yield Data of Paddy Crop
Treatment Yield (kg!ha)
T1 3997
T2 4878
T, 5278
T. 5289
T, 4952
T• 5026
T1 5324
*SEm± 255
CDS% 753
*SEm ±:Standard Errors of Means; CD 5%: Critical Difference
The aforementioned trial results indicate that the dry flowable herbicidal
composition (Fenoxaprop-p-Ethyl 9% DF @ 250 gm/acre) of the present
invention is most effective against the target weeds and affords better crop
attributes, such as fresh green leaves and good strength of plant with better
growth. Commercially available Fenoxaprop 9.3% EC was less effective against
weeds compared to the dry flowable herbicidal compositions of the present
invention.

We claim:
I. A dry flowable herbicidal composition, comprising:
(a) fenoxaprop-p-ethyl;
(b) a safener; and
(c) at least one excipient selected from the group consisting of
wetting agent, dispersing agent, anti foaming agent, and filler.
2. The dry flowable herbicidal composition, as claimed in claim I, wherein
fenoxaprop-p-ethyl is present in an amount in the range from 5 to 15%
w/w.
3. The dry flowable herbicidal composition, as claimed in clam I, wherein
the safener is present in an amount of 2.90% and selected from the group
consisting of cloquintocet mexyl, isoxadifen ethyl, and mefenpyr diethyl.
4. The dry flowable herbicidal composition, as claimed in claim 3, wherein
the safener is preferably mefenpyr diethyl.
5. The dry flowable herbicidal composition, as claimed in claim 1, wherein,
the wetting agent is present in an amount in the range from 2 to 4% and is
sodium disopropyl naphthalene sulfonate.
6. The dry flowable herbicidal composition, as claimed in claim 1, wherein,
the dispersing agent is present in an amount in the range from 8.00 to 14%
w/w and is sodium polycarboxylate.
7. The dry flowable herbicidal composition as claimed in claim I, wherein,
the anti foaming agent is present in an amount of 0.1 to 1% w/w and is
1572 SAG (Polydimethyl Siloxane).
8. The dry flowable herbicidal composition as claimed in claim 1, wherein,
the filler is china clay (kaolin).
9. The dry flowable herbicidal composition, as claimed in any of the claims 1
to 8, wherein said composition controls and prevents annual grassy and
monocot weeds.
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10. The dry flowable herbicidal composition, as claimed in any of the claims 1
to 8, wherein said composition controls and prevents crop weeds in
cereals, pulses and oilseeds.
11. A process for preparing the dry flowable herbicidal composition as
claimed in claim 1, comprising the steps of:
(a) mixing all the excipients in a pre-blender to form a homogenous
mixture;
(b) adding fenoxaprop-p-ethyl and safener and grinding in an au
classifying mill/jet mill at 2000 rpm;
(c) adding requisite quantity of water to make a dough and passing
through extruder mill maintained at a temperature of SO · C to
produce granules of desired dimensions;
(d) drying the granules obtained in step (c) in a dryer to obtain dried
granules; and
(e) sieving the dried granules obtained in step (d) to obtain dried
granules of desired dimensions.