FIELD OF THE INVENTION
[0001] The present disclosure relates to a synergistic herbicidal composition for control of sedges, narrow leaf weeds and broad leaf weeds in maize (Zea mays L) crop. Specifically it pertains to a synergistic herbicidal composition including a combination of an effective amount of Halosulfuron methyl and an effective amount of Atrazine in specific weight percentages along with at least one agro chemically acceptable excipient for control of sedges (specifically Cyperus rotundus), narrow leaf weeds and broad leaf weeds in maize (Zea mays L) crop. The present disclosure further relates to a process for the preparation of composition(s) thereof.
BACKGROUND OF THE INVENTION
[0002] Background description includes information that may be useful in understanding the present invention. It is not an admission that any of the information provided herein is prior art or relevant to the presently claimed invention, or that any publication specifically or implicitly referenced is prior art.
[0003] Maize (Zea mays L) is one of the most versatile cereal crops having wider adaptability under diverse soil and climatic conditions. Globally, maize is known as the queen of cereals because it has the highest genetic yield potential amongst the cereals owing to its better dry matter accumulation efficiency in a unit area and time particularly upto 30° North and South latitude. Maize was first used as a source of food by ancient American and Indian civilizations and it also played an important role in their cultural heritage. These civilizations were responsible for its early domestication and utilization which helped to spread its acreage in various parts of the world. Today, maize has become one of the leading food grain crops in many parts of the world, not only in tropical and subtropical areas but also in temperate and high hill ecologies. It is cultivated in an area of about 150 M ha in 160 countries in diverse soil types, climate, and management practices with wider plant biodiversity that contributes about 36% towards the global food grain production.
[0004] Maize (Zea mays L) is the third most important crop of India after rice and wheat that occupies an area of about 8.67 M ha with an average productivity of about 2.57 t/ha compared to the world average productivity of about 4.94 t/ha (Anonymous 2014). As maize has wide adaptability and compatibility under diverse soil and climatic conditions, it is considered as
3
one of the potential drivers of crop diversification under different situations and is cultivated in sequence with different crops under various agro-ecologies of the country. Karnataka occupies highest acreage of 1.19 m ha, followed by Rajasthan 0.99 m ha, Madhya Pradesh 0.90 m ha, Maharashtra 0.74 m ha, Uttar Pradesh 0.70 m ha and Telangana 0.46 m ha. In India, Maize is cultivated during rainy season, winter season and summer season for feed and fodder. Recently, it is also being used as Pop-corn, Babycorn and Sweat Corn.
[0005] However, in Maize, about 75 types of narrow and broad leaf weeds and sedges have been reported in different States of Indian Union. The Eleusine aegyptiaca, Eragrostis tenella, Laptochloa panicea, Trianthema portulacastrum, Digera arvensis, Panicum colonum, Digitaria ciliaris, Sorghum halepense, Commelina benghalensis, Celosia argentea, Cleome viscose, Euphorbia hirta, Amaranthus viridis, Cyperus rotundus, Brachiaria reptans, Polygonum glabrum, Ageratum conyzoides etc. have been reported as major weed flora across the country. (Sandhu, et al. 1999; Indian J. Weed Science, 31 : 18-24). Weeds compete with the maize for space, moisture, nutrients, light and if left uncontrolled, can reduce maize yield by 29 to 74%.
[0006] Traditionally hand weeding has been the pre-dominant method for weed control used by farmers in India. But due to shortage of labourers, frequent monsoon rains, cost involved, manual weeding is considerably delayed or not followed, resulting to severe weed problems culminating to grain yield losses.
[0007] Researchers in the agricultural field had spent significant amount of efforts on developing chemical formulations exhibiting excellent herbicidal activity towards target weeds, low phytotoxicity towards non-target plants, lower undesirable effect on the environment, having lower manufacturing and market costs as compared to existing marketed formulations, having herbicidal activity against broad-spectrum of weeds. However, there is a long-standing need for selective herbicides which will control frequently occurring weeds but which do not adversely affect the maize crops when applied at herbicidally effective levels.
[0008] Halosulfuron methyl with CAS registration number 100784-20-1, is a derivative of Halosulfuron and is pyrazole herbicide or pyrimidinylsulfonylurea herbicide. Its IUPAC name is methyl 3-chloro-5-(4, 6-dimethoxypyrimidin-2-ylcarbamoylsulfamoyl)-1-methylpyrazole-4-carboxylate. Halosulfuron methyl, is being used in herbicidal formulations alone or in combination with other herbicidal agents such as bromoxynil, dicamba, nicosulfuron, glyphosate, mesotrione, primisulfuron, 2,4-D against broadleaf weeds, nutsedge such as yellow nutsedge (Cyperus esculentus) and purple nutsedge (Cyperus rotundus), horsetail (Equisetum arvense), kyllinga, cocklebur, common sunflower, common ragweed, wild mustard, giant ragweed,
4
pigweed, venice mallow, velvetleaf, etc. Predominantly because of its interference with acetolactate synthase (ALS) enzyme, it results in a rapid termination of cell division and plant growth in both roots and shoots by blocking the synthesis of the branched-chain amino acids isoleucine, lecucine, and valine, consequently controlling the sedges and other weeds.
[0009] Atrazine with CAS registration number 1912-24-9, acts as herbicide by inhibiting photosynthesis of plants. Its IUPAC name is 1-Chloro-3-ethylamino-5-isopropylamino-2,4,6-triazine. Atrazine, is being used in herbicidal formulations alone or in combination with other herbicidal agents such as callisto, mesotrione, bromoxynil, sulfosate, paraquat, metolachlor, cyanazine, alachlor, glyphosate, acetochlor, dicamba, dimethenamid, flufenacet, metribuzin, pendimethalin, 2,4-D, simazine, nicosulfuron, thifensulfuron against broadleaf weeds, waterhemps, lambsquarters, wild radish (Raphanus raphanistrum), giant ragweed etc. Atrazine, being a a photosystem II (PS II) inhibitor, results in plant death from starvation and oxidative damage caused by breakdown in the process of electron transport, thereby controlling the weeds.
[0010] CN104522021 discloses the herbicidal formulation combination of Halosulfuron-methyl, Atrazine and Nicosulfuron. However, CN’021 fails to disclose, teach, motivate or suggest a person skilled in the art to develop formulation(s) comprising Halosulfuron-methyl and Atrazine as active ingredients exhibiting desired herbicidal effect. The disclosure of CN’021 necessitates inclusion of Nicosulfuron for achieving desired herbicidal activity.
[0011] For the control of weeds, application of Atrazine 50% WP at 1 to 1.5 kg active ingredient/hectare (hereinafter referred to as “a.i./ha”) has been recommended in several reports either as pre-emergence or early post-emergence (Kumar et al., 2012; Indian J. Weed Science, 44 : 11-17; Kumar et al., 2012; Indian J. Weed Science, 40 : 47-50; Walia et al., 2007. Indian J. Weed Science; 39 : 17-20). However, Atrazine 50% WP controls only narrow and broad leaf weeds. In maize cropping systems, Sedges, Cyperus rotundus has been reported to be a serious weed problem. Cyperus rotundus, due to presence of a chain of 5-8 underground tubers, its control/eradication has been a difficult task. Cyperus rotundus proliferates vigorously after manual inter-culture operations and also hand weeding due to damage of rhizome and development of new plants from nuts. Halosulfuron methyl 75% WG at 67.5 g a.i./ha, as post-emergence, has been recently recommended for the control of Cyperus rotundus.
[0012] There is, therefore, a need in the art to develop a new composition which is free from the existing drawbacks of the compositions used as herbicides. Need is also observed to develop composition that has different active ingredients with different mechanisms of actions to ensure maximum efficacy, while making sure compatibility of all the ingredients used. Further,
5
agricultural field is in dire need of composition(s) exhibiting excellent synergistic herbicidal activity towards target weeds, low toxicity towards non-target plants, lower undesirable effect on the environment, having lower manufacturing and market costs as compared to existing marketed compositions and having herbicidal activity against broad-spectrum of weeds.
[0013] All publications herein are incorporated by reference to the same extent as if each individual publication or patent application were specifically and individually indicated to be incorporated by reference. Where a definition or use of a term in an incorporated reference is inconsistent or contrary to the definition of that term provided herein, the definition of that term provided herein applies and the definition of that term in the reference does not apply.
[0014] In some embodiments, the numbers expressing quantities of ingredients, properties such as concentration, reaction conditions, and so forth, used to describe and claim certain embodiments of the invention are to be understood as being modified in some instances by the term “about.” Accordingly, in some embodiments, the numerical parameters set forth in the written description and attached claims are approximations that can vary depending upon the desired properties sought to be obtained by a particular embodiment. In some embodiments, the numerical parameters should be construed in light of the number of reported significant digits and by applying ordinary rounding techniques. Notwithstanding that the numerical ranges and parameters setting forth the broad scope of some embodiments of the invention are approximations, the numerical values set forth in the specific examples are reported as precisely as practicable. The numerical values presented in some embodiments of the invention may contain certain errors necessarily resulting from the standard deviation found in their respective testing measurements.
[0015] As used in the description herein and throughout the claims that follow, the meaning of “a,” “an,” and “the” includes plural reference unless the context clearly dictates otherwise. Also, as used in the description herein, the meaning of “in” includes “in” and “on” unless the context clearly dictates otherwise.
[0016] The recitation of ranges of values herein is merely intended to serve as a shorthand method of referring individually to each separate value falling within the range. Unless otherwise indicated herein, each individual value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g. “such as”) provided with respect to certain embodiments herein is intended merely to better illuminate the invention and does not pose a
6
limitation on the scope of the invention otherwise claimed. No language in the specification should be construed as indicating any non-claimed element essential to the practice of the invention.
[0017] Groupings of alternative elements or embodiments of the invention disclosed herein are not to be construed as limitations. Each group member can be referred to and claimed individually or in any combination with other members of the group or other elements found herein. One or more members of a group can be included in, or deleted from, a group for reasons of convenience and/or patentability. When any such inclusion or deletion occurs, the specification is herein deemed to contain the group as modified thus fulfilling the written description of all markush groups used in the appended claims.
OBJECTS OF THE INVENTION
[0018] It is an object of the present disclosure is to provide a composition which is free from the existing drawbacks of the herbicidal compositions.
[0019] Yet another object of the present disclosure is to provide a composition which is more effective than the compositions currently being used as herbicide.
[0020] Yet another object of the present disclosure is to provide composition which is synergistic and combines the therapeutic benefits of the herbicides i.e. Atrazine and Halosulfuron methyl in specific weight percentages along with at least one agrochemically acceptable excipient.
[0021] Yet another object of the present disclosure is to provide a process for the preparation of a herbicidal composition including effective amounts of Atrazine and Halosulfuron methyl.
[0022] Yet another object of the present disclosure is to provide synergistic herbicidal composition specifically effective against sedges, narrow leaf weeds and broad leaf weeds in maize crop.
[0023] Yet another object of the present disclosure is to provide a synergistic herbicidal composition capable of providing high yield of maize crops.
[0024] Yet another object of the present disclosure is to provide composition having low toxicity towards non-target plants.
[0025] Yet another object of the present disclosure is to provide composition having lower undesirable effect on the environment.
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[0026] Yet another object of the present disclosure is to provide composition having lower manufacturing and market costs as compared to existing marketed compositions.
SUMMARY OF THE INVENTION
[0027] The present disclosure relates to a synergistic herbicidal composition for control of sedges, narrow leaf weeds and broad leaf weeds in maize (Zea mays L) crop. Specifically it pertains to a synergistic herbicidal composition including a combination of an effective amount of Halosulfuron methyl and an effective amount of Atrazine in specific weight percentages along with at least one agro chemically acceptable excipient for control of sedges (specifically Cyperus rotundus), narrow leaf weeds and broad leaf weeds in maize (Zea mays L) crop. The present disclosure further relates to a process for the preparation of composition(s) thereof.
[0028] An aspect of the present disclosure provides a stable and nontoxic synergistic herbicidal composition including a combination of: (a) Halosulfuron methyl in an amount of about 5% by weight of the composition; (b) Atrazine in an amount of about 48% by weight of the composition; and (c) at least one agro chemically acceptable excipient.
[0029] Another aspect of the present disclosure relates to a process for the preparation of a synergistic herbicidal composition, the process including the steps of: taking Halosulfuron methyl in an amount of about 5% by weight of the composition; mixing Atrazine in an amount of about 48% by weight of the composition with Halosulfuron methyl; mixing the at least one agriculturally acceptable excipient in an appropriate amount by weight of herbicidal composition in a homogenizer mixer; milling the prepared mixture obtained in step above using a conventional mill to obtain an average particular size mill base; and granulating the mill base in a conventional drier at a suitable temperature to obtain the herbicidal composition.
[0030] In an embodiment of the present disclosure, the herbicidal composition can be in the form of solid or liquid. In an preferred embodiment of the present disclosure, the composition can be in the form of water dispersible granules (WG), suspension concentrates (SC), wettable powders (WP), emulsifiable concentrates (EC), granules, gel, suspo emulsions (SE), mixed composition of capsule suspension and suspension concentrates (ZC) and the like and preferably, water dispersible granules (WG), suspo emulsions (SE) and mixed composition of capsule suspension and suspension concentrates (ZC).
[0031] In an embodiment of the present disclosure, the herbicidal composition can be applied by using at least one technique selected from the group consisting of spraying, rubbing, dusting, pouring, mist blowing, soil mixing, dipping, drip irrigation and other irrigations. In an
8
embodiment of the present disclosure, the composition comprising Halosulfuron methyl and Atrazine in specific weight percentages exhibits an excellent herbicidal activity against sedges (Cyperus rotundus), narrow leaf weeds and broad leaf weeds. In another preferred embodiment of the disclosure, the composition comprising Halosulfuron methyl and Atrazine in specific weight percentages exhibits an excellent herbicidal activity against Eleusine aegyptiaca, Eragrostis tenella, Laptochloa panicea, Trianthema portulacastrum, Digera arvensis, Panicum colonum, Digitaria ciliaris, Sorghum halepense, Commelina benghalensis, Celosia argentea, Cleome viscose, Euphorbia hirta, Amaranthus viridis, Cyperus rotundus, Brachiaria reptans, Polygonum glabrum, Ageratum conyzoides and the like in maize crop.
DETAILED DESCRIPTION OF THE INVENTION
[0032] The embodiments herein and the various features and advantageous details thereof are explained more comprehensively with reference to the non-limiting embodiments that are detailed in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein.
[0033] The present disclosure relates to a synergistic herbicidal composition for control of sedges, narrow leaf weeds and broad leaf weeds in maize (Zea mays L) crop. Specifically it pertains to a synergistic herbicidal composition including a combination of an effective amount of Halosulfuron methyl and an effective amount of Atrazine in specific weight percentages along with at least one agro chemically acceptable excipient for control of sedges (specifically Cyperus rotundus), narrow leaf weeds and broad leaf weeds in maize (Zea mays L) crop. The present disclosure further relates to a process for the preparation of composition(s) thereof.
[0034] Unless otherwise specified, all terms used in disclosing the invention, including technical and scientific terms, have the meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. By means of further guidance, term definitions may be included to better appreciate the teaching of the present invention.
[0035] As used herein, the term “plant” refers to any plant or part thereof including aerial and subterranean parts of the plant. It is contemplated that the parts of the plant may be, for example, flowers, fruits or vegetables, shoots, leaves, needles, stalks, stems, fruiting bodies, seeds, also roots, and that the parts of the plant may or may not be attached to the remainder of the plant
[0036] As used herein, the term “weed” refers to unwanted plant harmful to plant.
9
[0037] As used herein, the term “herbicide” refers to as employed in the specification and claims of the application is confined to the means, which adversely affects the existence, growth of the target weed.
[0038] As used herein, the term “effective amount” is that quantity of active agent, applied in an amount which will provide the required control of weed on commercial crops. The particular amount is dependent upon many factors including, for example, type of formulations, the crop, weed sought to be controlled and environmental conditions.
[0039] As used herein, the term “control” as employed in the specification and claims of the application is to be construed as meaning herbicidal or protecting plants from weed.
[0040] As used herein, the term “WP” refers to a wettable powder, which can be a powder formulation to be applied as a suspension after dispersion in water.
[0041] As used herein, the term “SE” refers to Suspo emulsion, which is a fluid heterogeneous formulation consisting of active ingredients in the form of solid particles and fine globules in continuous water phase.
[0042] As used herein, “WG” or “WDG” refer to water dispersible granules which can be defined herein as herbicide formulation consisting of granules to be applied after disintegration and dispersion in demineralized water.
[0043] As used herein, “SC” refers to suspension concentrates which is defined herein as a stable suspension of solid herbicides in a fluid usually intended for dilution with water before use.
[0044] As used herein, “WP” refers to a wettable powder, which can be a powder formulation to be applied as a suspension after dispersion in water.
[0045] As used herein, “EC” refers to an emulsifiable concentrate, which can be a liquid homogenous formulation to be applied as an emulsion after dilution in water.
[0046] As used herein, “SE” refers to suspo-emulsion which is a formulation containing both solid and liquid active ingredients dispersed in an aqueous phase.
[0047] As used herein, “ZC” refers to a stable mixed formulation of capsule suspension and suspension concentrates, in fluid, normally intended for dilution with water before use.
[0048] As used herein, the term “agrochemical excipient” refers to an ingredient, additive, component or supplement, liquid or solid, suitable for incorporation in agricultural compositions.
[0049] As used in the description herein, the meaning of “a,” “an,” and “the” includes plural reference unless the context clearly dictates otherwise. Also, as used in the description herein, the meaning of “in” includes “in” and “on” unless the context clearly dictates otherwise.
10
[0050] As used herein, the term “combination” refers to materials added together with or without substantial mixing towards achieving homogeneity.
[0051] As used herein, the term “mix” refers to adding materials together and achieving homogeneity, and the term “mixture” refers to mixed materials achieving homogeneity.
[0052] As used herein, the terms “comprise”, “comprises”, “comprising”, “include”, “includes”, and “including” are meant to be non- limiting, i.e., other steps and other ingredients which do not affect the end of result can be added. The above terms encompass the terms “consisting of” and “consisting essentially of”.
[0053] The terms “weight percent,” “wt-%,” “percent by weight,” “% by weight,” and variations thereof, as used herein, refer to the concentration of a substance as the weight of that substance divided by the total weight of the composition and multiplied by 100. It is understood that, as used here, “percent,” “%,” and the like are intended to be synonymous with “weight percent,” “wt-%,” etc.
[0054] Various embodiments of the present disclosure provide stable and nontoxic combination compositions comprising Halosulfuron methyl and Atrazine. In an embodiment, the composition includes an appropriate amount of Halosulfuron methyl by weight of the composition. In an embodiment of the present disclosure, the composition further includes an appropriate amount of Atrazine by weight of the composition. In an embodiment, the composition is capable of exhibiting synergistic herbicidal activity at much lesser amounts of Halosulfuron methyl and Atrazine as compared to the amounts when used alone.
[0055] Surprisingly, the herbicidal composition of the present disclosure exhibits superior weed control at much lower levels of the combined specific concentrations of the active agents employed than that may be achieved when the active ingredients are applied alone. Accordingly, an aspect of the present disclosure relates to a synergistic herbicidal composition including a combination of: (a) Halosulfuron methyl in an amount of about 5% by weight of the composition; (b) Atrazine in an amount of about 48% by weight of the composition; and (c) at least one agro chemically acceptable excipient. In a preferred embodiment, a combination of Halosulfuron methyl in an amount of about 56.2 g a.i./ha and Atrazine in an amount of about 540 g a.i./ha is applied to yield a strong synergistic herbicidal effect against broad range of narrow leaf weeds, broad leaf weeds and sedges (specifically Cyperus rotundus).
[0056] In an embodiment, the composition further includes at least one agrochemically acceptable excipient selected from the group consisting of wetting agents, emulsifying agents, fillers, diluents, thickening agents, solvents, coating agents, dispersing agents, preservatives,
11
antifoaming agent and stabilizers. However, those skilled in the art will appreciate that the additional agrochemically acceptable excipients can be used without departing from the scope and spirit of the present invention. In an embodiment, the agrochemically acceptable excipient can be used in an appropriate range of the total weight of the present composition.
[0057] In an embodiment, the wetting agents can be selected from the group consisting of sulfosuccinates, naphthalene sulfonates, sulfated esters, phosphate esters, sulfated alcohol and alkyl benzene sulfonates and the like as known to a person skilled in the art.
[0058] In an embodiment, the dispersing agents can be selected from the group consisting of polycarboxylates, naphthalene sulfonate condensates, phenol sulfonic acid condensates, lignosulfonates, methyl oleyl taurates, polyvinyl alcohols and the like as known to a person skilled in the art.
[0059] In an embodiment, the emulsifiers can be of the anionic, cationic or non-ionic type. The emulsifiers can be selected from a group consisting of ethoxylated and ethopropoxylated alcohols and nonyl phenols, ethoxylated tristeryl phenol, sodium lauryl sulphate, ethoxylated tristeryl phenol phosphates, ethoxylated and ethopropoxylated castor oil, calcium alkyl benzene sulfonates, proprietary blended emulsifiers and the like as known to a person skilled in the art.
[0060] In an embodiment, the fillers can be selected from a group consisting of diatomaceous earth, China clay, kaolin, bentonite, precipitated silica, attapulgite, perlite and/or the mixture thereof. However, those skilled in the art will appreciate that any other filler can also be used without departing from the scope and spirit of the present invention.
[0061] In an embodiment, the diluents can be selected from the group consisting of tone calcite, mica, soap powder, dolomite and lactose and the like as known to a person skilled in the art.
[0062] In an embodiment of the present disclosure, the anti-foaming agent can be selected from silicon emulsion based anti foam agents, trisiloxane ethoxylates, etc.
[0063] In an embodiment of the present disclosure, the thickening agent can be selected from a group consisting of natural gums, resins, carboxy methyl cellulose and the like as known to a person skilled in the art.
[0064] In an embodiment of the present disclosure, the herbicidal composition can be in the form of solid or liquid.
[0065] In a preferred embodiment of the present disclosure, the composition can be formulated as, including but not limited to, water dispersible granules (WG), suspension concentrates (SC), wettable powders (WP), emulsifiable concentrates (EC), granules, gel, suspo
12
emulsions (SE), mixed composition of capsule suspension and suspension concentrates (ZC) and the like.
[0066] In another embodiment of the present disclosure, the herbicidal composition can be prepared by various processes depending upon the composition types as known to a person skilled in the art.
[0067] In an embodiment of the present disclosure, the herbicidal composition is preferably prepared by a process that includes following steps: (a) taking Halosulfuron methyl in an appropriate amount by weight of the composition; (b) mixing Atrazine in an appropriate amount by weight of the composition with the Halosulfuron methyl or Halosulfuron; (c) mixing the at least one agriculturally acceptable excipient in an appropriate amount by weight of herbicidal composition in a homogenizer mixer; (d) milling the prepared mixture obtained in step (c) using a conventional mill to obtain an average particular size mill base; and (e) granulating the mill base in a conventional drier at a suitable temperature to obtain the herbicidal composition.
[0068] In a preferred embodiment, the conventional mill as used in step (d) can be selected from a group consisting of fluid energy mill, jet mill, pin mill, hammer mill and the like.
[0069] In a preferred embodiment, the conventional drier as used in step (e) can be selected from a group consisting of spray drier, fluidized bed drier and the like.
[0070] Accordingly, another aspect of the present disclosure relates to a process for the preparation of a synergistic herbicidal composition, the process including the steps of: taking Halosulfuron methyl in an amount of about 5% by weight of the composition; mixing Atrazine in an amount of about 48% by weight of the composition with Halosulfuron methyl; mixing the at least one agriculturally acceptable excipient in an appropriate amount by weight of herbicidal composition in a homogenizer mixer; milling the prepared mixture obtained in step above using a conventional mill to obtain an average particular size mill base; and granulating the mill base in a conventional drier at a suitable temperature to obtain the herbicidal composition.
[0071] In an embodiment of the present disclosure, the mode of application of synergistic herbicidal composition can be by using at least one technique selected from the group consisting of spraying, rubbing, dusting, pouring, mist blowing, soil mixing, dipping, drip irrigation and other irrigations. However, those skilled in the art will appreciate that any other mode of application can also be used without departing from the scope and spirit of the present invention.
[0072] In another preferred embodiment of the present disclosure, the composition can be used for controlling weeds which grow near to a particular plant, very especially in crop plants, in agricultural, in horticulture and in forests.
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[0073] In another embodiment of the present disclosure, the synergistic herbicidal composition can be applied advantageously for control of narrow and broad leaf weeds such as Eleusine aegyptiaca, Eragrostis tenella, Laptochloa panicea, Trianthema portulacastrum, Digera arvensis, Panicum colonum, Digitaria ciliaris, Sorghum halepense, Commelina benghalensis, Celosia argentea, Cleome viscose, Euphorbia hirta, Amaranthus viridis, Cyperus rotundus, Brachiaria reptans, Polygonum glabrum, Ageratum conyzoides and the like in maize crops.
[0074] In an embodiment, the amount of synergistic herbicidal composition depends upon many factors including but not limited to type of compositions, the crop, weed sought to be controlled and environmental conditions.
[0075] While certain embodiments have been shown and described, various modifications and substitutions may be made thereto without departing from the scope and spirit of the disclosure. Therefore, it is to be understood that the present disclosure has been described by way of illustration and not limitations.
EXAMPLES
[0076] Surprisingly, it was found that Atrazine and Halosulfuron methyl, when applied as tank-mix, exhibit a strong synergistic action and the combination controls all three types of weeds namely narrow leaf weeds, broad leaf weeds and sedges (specifically Cyperus rotundus).
[0077] Further, it was also found that Atrazine and Halosulfuron methyl exhibits maximum synergistic herbicidal activity when applied at an amount of about 56.2 gram active ingredient/hectare (hereinafter referred to as “g a.i./ha”) of Halosulfuron methyl and 540 g a.i./ha of Atrazine. To find out synergistic efficacy and optimum dose, initially, a number of trials were undertaken with different tank-mix combinations. Further, a number of compositions with Halosulfuron methyl at 56.2 g a.i./ha and Atrazine at 540 g a.i./ha with variable surfactants, emulsifiers, stabilizers were developed and tested in laboratory and field as pre and post-emergence, to find suitability, efficacy, optimum dose, etc. The composition, which has given good control of weeds, without any phytotoxicity, was further evaluated in the fields as pre and post-emergence with replicated experiments in different States.
[0078] The field experiments results, as mentioned in Tables 1 through 6 below, reveal that pre-mix composition of Halosulfuron methyl at 56.2 g a.i./ha and Atrazine at 540 g a.i./ha, applied as pre-emergence, recorded at par control of Cyperus rotundus weed compared to Halosulfuron methyl at 67.5 g a.i./ha. Similarly, pre-mix composition also gave at par or better
14
control of narrow and broad leaf weeds compared to individual application of Atrazine at 625 g a.i./ha. Thus, results clearly reveal that pre-mix combination exhibits strong synergy against Cyperus rotundus, narrow & broad leaf weeds when applied as pre-emergence, recording at par or better control of weeds compared to less active ingredients of both herbicides. The utility of Halosulfuron methyl for controlling Cyperus rotundus as pre-emergence application was established in India for the first time as revealed in the results provided in Tables 1 through 6 below.
[0079] Similarly, field experiments conducted as post-emergence application (Table 7-9) of pre-mix composition of Halosulfuron methyl at 56.2 g a.i./ha and Atrazine at 540 g a.i./ha recorded at par control of Cyperus rotundus compared to individual application of Halosulfuron methyl at 67.5 g a.i./ha and also at par control of narrow & broad leaf weeds compared to Atrazine at 540 g a.i./ha, indicating a strong synergy for the control of Cyperus rotundus, narrow & broad leaf weeds even at the lower doses of both, Halosulfuron methyl and Atrazine in pre-mix composition.
Table 1:- Effect of different herbicidal treatments applied as pre-emergence on the weed flora of Maize
Sl. No.
Treatments
a.i. (g/ha)
Formulation (g/ha)
Mean No. of weeds/0.25 sq.m. at 3 places in each treatment
Sedges
Narrow leaf weeds
Broad leaf weeds
15 DAT
29 DAT
15 DAT
29 DAT
15 DAT
29 DAT
1
DAH – 302 (Halosulfuron methyl 5% + Atrazine 48% WG)
56.2 + 540
1125
27.67 {5.34} (77.06%)
3.66 {2.14} (97.19%)
14.70 {3.96} (4.11%)
18.33 {4.38} (4.03%)
0.00 {1.00} (100%)
0.00 {1.00} (100%)
2
DAH – 302
(Halosulfuron methyl 5% +
62.5 + 600
1250
24.33 {5.02}
(79.83
3.00 {1.98}
(97.69
9.0 {3.15}
(41.29
15.66 {4.07}
0.00 {1.00} (100%)
0.00 {1.00}
15
Atrazine 48% WG)
%)
%)
%)
(18.01%)
(100%)
3
Halosulfuron methyl 75% WG
67.5
90
25.70 {5.16} (78.69%)
3.10 {2.01} (97.62%)
15.10 {4.00} (1.50%)
18.90 {4.45} (1.05%)
7.40 {2.88} (-80.49%)
5.90 {2.60} (-13.46%)
4
Atrazine 50% WP
625
1250
110.60 {10.56} (8.29%)
125.40 {11.24} (3.61%)
7.40 2.85} (51.73%)
8.30 {3.02} (56.54%)
1.10 {1.44} (73.17%)
1.90 {1.68} (63.46%)
5
Untreated Control
120.60 {11.02}
130.10 {11.44}
15.33 {4.02}
19.10 {4.47}
4.10 {2.19}
5.20 {2.45}
SEM (±)
{0.12}
{0.15}
{0.27}
{0.24}
{0.17}
{0.13}
CD 5%
{0.41}
{0.51}
N/A
{0.80}
{0.59}
{0.45}
Figures in parentheses {} are converted to √x+1 Figures in parentheses ( ) indicate percent weed control over untreated control DAT: Days after treatment Table 2:- Effect of different herbicidal treatments applied as pre-emergence on the weed flora of Maize
Sl. No.
Treatments
a.i. (g/ha)
Formulation (g/ha)
Mean No. of weeds/0.25 sq.m. at 3 places in each treatment
Sedges
Narrow leaf weeds
Broad leaf weeds
16
12 DAT
28 DAT
12 DAT
28 DAT
12 DAT
28 DAT
1
DAH – 302 (Halosulfuron methyl 5% + Atrazine 48%WG)
56.2 + 540
1125
4.33 {2.30} (93.84%)
4.33 {2.28} (94.47%)
0.00 {1.00} (100%)
3.00 {1.99} (70.00%)
0.00 {1.00} (100%)
0.00 {1.00} (100%)
2
DAH – 302 (Halosulfuron methyl 5% + Atrazine 48%WG)
62.5 + 600
1250
3.33 {2.03} (95.27%)
4.00 {2.22} (94.89%)
0.00 {1.00} (100%)
1.33 {1.52} (86.70%)
0.00 {1.00} (100%)
0.00 {1.00} (100%)
3
Halosulfuron methyl 75% WG
67.5
90
2.10 {1.74} (97.01%)
1.90 {1.68} (97.57%)
2.40 {1.81} (34.43%)
2.10 {1.74} (79.00%)
3.10 {1.98} (31.11%)
3.40 {2.06} (32.00%)
4
Atrazine 50% WP
625
1250
68.90 {8.35} (2.0%)
78.10 {8.89} (0.2%)
0.00 {1.00} (100%)
0.00 {1.00} (100%)
2.10 {1.72} (53.33%)
1.90 {1.68} (62.0%)
5
Untreated Control
70.33 {8.44}
78.33 {8.90}
3.66 {2.11}
10.00 {3.30}
4.50 {2.27}
5.00 {2.41}
SEM (±)
{0.19}
{0.18}
{0.18}
{0.13}
{0.25}
{0.15}
CD 5%
{0.63}
{0.61}
{0.61}
{0.45}
{0.85}
{0.52}
Figures in parentheses {} are converted to √x+1 Figures in parentheses ( ) indicate percent weed control over untreated control DAT: Days after treatment
17
Table 3:- Effect of different herbicidal treatments applied as pre-emergence on the weed flora of Maize
Sl. No.
Treatments
a.i. (g/ha)
Formulation (g/ha)
Mean No. of weeds/0.25 sq.m. at 3 places in each treatment
Sedges
Narrow leaf weeds
Broad leaf weeds
19 DAT (Before irrigation)
50 DAT (After irrigation)
19 DAT (Before irrigation)
50 DAT (After irrigation)
19 DAT (Before irrigation)
50 DAT (After irrigation)
1
DAH – 302 (Halosulfuron methyl 5% + Atrazine 48%WG)
56.2 + 540
1125
33.33 {5.85} (26.47%)
9.33 {3.20} (81.94%)
0.00 {1.00} (100%)
2.33 {1.79} (41.75%)
0.00 {1.00} (100%)
0.00 {1.00} (100%)
2
DAH – 302 (Halosulfuron methyl 5% + Atrazine 48%WG)
62.5 + 600
1250
31.33 {5.68} (30.88%)
8.66 {3.09} (83.24%)
0.00 {1.00} (100%)
1.66 {1.62} (58.50%)
0.00 {1.00} (100%)
0.00 {1.00} (100%)
3
Halosulfuron methyl 75% WG
67.5
90
30.40 {5.60} (32.94%)
7.10 {2.82} (86.26%)
3.00 {2.00} (18.03%)
3.90 {2.15} (2.50%)
9.24 {3.24} (18.45%)
10.11 {3.33} (22.23%)
4
Atrazine 50% WP
625
1250
44.70 {6.75} (1.39%)
50.40 {7.16} (2.44%)
0.00 {1.00} (100%)
0.00 {1.00}
(100%
5.40 {2.51}
(52.34%
5.30 {2.49}
18
)
)
(59.23%)
5
Untreated Control
45.33 {6.80}
51.66 {7.25}
3.66 {2.11}
4.00 {2.22}
11.33 {3.48}
13.00 {3.73}
SEM (±)
{0.10}
{0.22}
{0.19}
{0.20}
{0.16}
{0.14}
CD 5%
{0.36}
{0.74}
{0.64}
{0.66}
{0.55}
{0.47}
Figures in parentheses {} are converted to √x+1 Figures in parentheses ( ) indicate percent weed control over untreated control DAT: Days after treatment Table 4:- Effect of different herbicidal treatments applied as pre-emergence on the weed flora of Maize
Sl. No.
Treatments
a.i. (g/ha)
Formulation (g/ha)
Mean No. of weeds/0.25 sq.m. at 3 places in each treatment
Sedges
Narrow leaf weeds
Broad leaf weeds
20 DAT
50 DAT
20 DAT
50 DAT
20 DAT
50 DAT
1
DAH – 302 (Halosulfuron methyl 5% + Atrazine 48%WG)
56.2 + 540
1125
5.66 {2.56} (76.74%)
9.66 {3.25} (84.08%)
0.00 {1.00} (100%)
2.33 {1.79} (41.75%)
0.00 {1.00} (100%)
0.00 {1.00} (100%)
2
DAH – 302
(Halosulfuron methyl 5% +
62.5 + 600
1250
4.33 {2.27}
(82.20
7.33 {2.85}
(87.92
0.00 {1.00}
(100%
3.00 {1.95}
(25.00
0.00 {1.00}
(100%
0.00 {1.00}
(100%
19
Atrazine 48%WG)
%)
%)
)
%)
)
)
3
Halosulfuron methyl 75% WG
67.5
90
3.90 {2.18} (83.97%)
8.10 {2.99} (86.65%)
2.90 {1.96} (3.33%)
3.80 {2.14} (5.00%)
10.60 {3.39} (39.98%)
13.90 {3.85} (26.84%)
4
Atrazine 50% WP
625
1250
23.70 {4.96} (2.59%)
58.90 {7.73} (2.90%)
0.00 {1.00} (100%)
1.10 {1.44} (72.50%)
2.10 {1.73} (88.11%)
3.00 {1.97} (84.21%)
5
Untreated Control
24.33 {5.03}
60.66 {7.85}
3.00 {1.98}
4.00 {2.19}
17.66 {4.31}
19.00 {4.46}
SEM (±)
{0.22}
{0.15}
{0.08}
{0.26}
{0.12}
{0.12}
CD 5%
{0.73}
{0.50}
{0.29}
N/A
{0.42}
{0.41}
Figures in parentheses {} are converted to √x+1 Figures in parentheses ( ) indicate percent weed control over untreated control DAT: Days after treatment Table 5:- Effect of different herbicidal treatments applied as pre-emergence on the weed flora of Maize
Sl. No.
Treatments
a.i. (g/ha)
Formulation (g/ha)
Mean No. of weeds/0.25 sq.m. at 3 places in each treatment
Sedges
Narrow leaf weeds
Broad leaf weeds
20 DAT
50 DAT
20 DAT
50 DAT
20 DAT
50 DAT
1
DAH – 302
(Halosulfuron methyl 5% + Atrazine
56.2 + 540
1125
12.00 {3.59} (80.11%)
10.33 {3.35}
(85.52
4.33 {2.28} (43.47%)
5.33 {2.48} (48.40%)
1.33 {1.52} (73.40%)
1.00 {1.41}
(84.20
20
48%WG)
%)
%)
2
DAH – 302 (Halosulfuron methyl 5% + Atrazine 48%WG)
62.5 + 600
1250
9.33 {3.17} (84.54%)
10.00 {3.29} (85.98%)
4.00 {2.20} (47.78%)
4.66 {2.35} (54.89%)
1.00 {1.40} (80.00%)
0.00 {1.00} (100%)
3
Halosulfuron methyl 75% WG
67.5
90
10.10 {3.32} (83.26%)
10.40 {3.36} (85.42%)
7.60 {2.90} (0.78%)
9.80 {3.28} (5.13%)
3.40 {2.04} (32.00%)
2.90 {1.95} (54.19%)
4
Atrazine 50% WP
625
1250
59.90 {7.80} (0.71%)
70.40 {8.44} (1.30%)
3.70 {2.14} (51.60%)
4.10 {2.23} (60.31%)
1.00 {1.41} (80.00%)
1.10 {1.44} (82.62%)
5
Untreated Control
60.33 {7.82}
71.33 {8.50}
7.66 {2.93}
10.33 {3.36}
5.00 {2.39}
6.33 {2.67}
SEM (±)
{0.24}
{0.20}
{0.27}
{0.23}
{0.21}
{0.15}
CD 5%
{0.80}
{0.67}
N/A
{0.79}
{0.70}
{0.50}
Figures in parentheses {} are converted to √x+1 Figures in parentheses ( ) indicate percent weed control over untreated control DAT: Days after treatment
21
Table 6:- Effect of different herbicidal treatments applied as pre-emergence on the weed flora of Maize
Sl. No.
Treatments
a.i. (g/ha)
Formulation (g/ha)
Mean No. of weeds/0.25 sq.m. at 3 places in each treatment
Sedges
Narrow leaf weeds
Broad leaf weeds
20 DAT
50 DAT
20 DAT
50 DAT
20 DAT
50 DAT
1
DAH – 302 (Halosulfuron methyl 5% + Atrazine 48%WG)
56.2 + 540
1125
32.66 {5.79} (54.21%)
11.33 {3.50} (86.77%)
6.40 {2.69} (55.34%)
5.30 {2.47} (66.16%)
0.00 {1.00} (100%)
0.00 {1.00} (100%)
2
DAH – 302 (Halosulfuron methyl 5% + Atrazine 48%WG)
62.5 + 600
1250
29.66 {5.53} (58.42%)
10.66 {3.39} (87.16%)
5.40 {2.49} (62.32%)
5.70 {2.54} (63.60%)
0.00 {1.00} (100%)
0.00 {1.00} (100%)
3
Halosulfuron methyl 75% WG
67.5
90
20.60 {4.64} (71.12%)
8.10 {3.00} (90.54%)
13.70 {3.81} (4.30%)
14.80 {3.96} (5.49%)
1.00 {1.41} (80.00%)
1.50 {1.57} (68.09%)
4
Atrazine 50% WP
625
1250
70.10 {8.43} (1.72%)
85.40 {9.29} (0.30%)
5.30 {2.47} (63.01%)
4.70 {2.35} (69.99%)
0.90 {1.37} (82.00%)
1.10 {1.44} (76.50%)
5
Untreated Control
71.33 {8.50}
85.66 {9.30}
14.33 {3.90}
15.66 {4.07}
5.00 {2.40}
4.70 {2.36}
SEM (±)
{0.16}
{0.18}
{0.30}
{0.27}
{0.14}
{0.11}
CD 5%
{0.55}
{0.60}
{1.00}
{0.90}
{0.48}
{0.36}
22
Figures in parentheses {} are converted to √x+1 Figures in parentheses ( ) indicate percent weed control over untreated control DAT: Days after treatment Table 7:- Effect of different herbicidal treatments applied as post-emergence on the weed flora of Maize
Sl. No.
Treatments
a.i. (g/ha)
Formulation (g/ha)
Mean No. of weeds/0.25 sq.m. at 3 places in each treatment
Sedges
Narrow leaf weeds
16 DAT
30 DAT
16 DAT
30 DAT
1
DAH – 302 (Halosulfuron methyl 5% + Atrazine 48%WG)
56.2 + 540
1125
10.00 {3.30} (94.00%)
15.33 {4.03} (92.76%)
1.00 {1.40} (85.01%)
3.33 {2.06} (53.00%)
2
DAH – 302 (Halosulfuron methyl 5% + Atrazine 48%WG)
62.5 + 600
1250
8.33 {3.03} (95.00%)
12.66 {3.67} (94.02%)
0.33 {1.15} (95.05%)
3.66 {2.12} (48.45%)
3
Halosulfuron methyl 75% WG
67.5
90
7.90 {2.97} (95.26%)
11.70 {3.55} (94.47%)
6.60 {2.75} (1.05%)
6.90 {2.79} (2.82%)
4
Atrazine 50% WP
625
1250
156.80 {12.56} (5.92%)
210.60 {14.54} (0.50%)
0.20 {1.09} (97.00%)
1.10 {1.44} (84.51%)
5
Untreated Control
166.67 {12.94}
211.66 {14.58}
6.67 {2.72}
7.10 {2.81}
SEM (±)
{0.16}
{0.12}
{0.20}
{0.23}
CD 5%
{0.53}
{0.41}
{0.68}
{0.77}
Figures in parentheses {} are converted to √x+1 Figures in parentheses ( ) indicate percent weed control over untreated control DAT: Days after treatment
23
Table 8:- Effect of different herbicidal treatments applied as post-emergence on the weed flora of Maize
Sl. No.
Treatments
a.i. (g/ha)
Formulation (g/ha)
Mean No. of weeds/0.25 sq.m. at 3 places in each treatment
Sedges
Narrow leaf weeds
Broad leaf weeds
16 DAT
30 DAT
16 DAT
30 DAT
16 DAT
30 DAT
1
DAH – 302 (Halosulfuron methyl 5% + Atrazine 48%WG)
56.2 + 540
1125
3.33 {2.06} (82.15%)
11.33 {3.50 } (95.52%)
1.00 {2.06} (72.68%)
1.33 {3.50} (72.86%)
0.00 {1.00} (100%)
0.00 {1.00} (100%)
2
DAH – 302 (Halosulfuron methyl 5% + Atrazine 48%WG)
62.5 + 600
1250
2.66 {1.88} (85.74%)
11.00 {3.44 } (95.65%)
1.33 {1.88} (63.66%)
1.00 {3.44} (79.59%)
0.00 {1.00} (100%)
0.00 {1.00} (100%)
3
Halosulfuron methyl 75% WG
67.5
90
2.30 {1.79} (87.67%)
10.11 {3.31} (96.00%)
3.40 {1.79} (7.10%)
4.00 {2.23} (18.37%)
0.90 {1.37} (24.44%)
1.00 {1.41} (70.59%)
4
Atrazine 50% WP
625
1250
17.90 {4.33} (4.07%)
240.00 {15.52} (5.14%)
1.00 {4.33} (72.68%)
1.10 {15.52} (77.55%)
1.10 {1.45} (47.62%)
1.70 {1.62} (50.00%)
5
Untreated Control
-
-
18.66 {4.43}
253.00 {15.93}
3.66 {4.43}
4.90 {15.93}
2.10 {1.74}
3.40 {2.07}
SEM (±)
{0.15}
{0.15}
{0.15}
{0.15}
{0.07}
{0.10}
CD 5%
{0.51}
{0.50}
{0.51}
{0.50}
{0.25}
{0.36}
Figures in parentheses {} are converted to √x+1
Figures in parentheses ( ) indicate percent weed control over untreated control
24
DAT: Days after treatment Table 9:- Effect of different herbicidal treatments applied as post-emergence on the weed flora of Maize
Sl. No.
Treatments
a.i. (g/ha)
Formulation (g/ha)
Mean No. of weeds/0.25 sq.m. at 3 places in each treatment
Sedges
Narrow leaf weeds
Broad leaf weeds
16 DAT
30 DAT
16 DAT
30 DAT
16 DAT
30 DAT
1
DAH – 302 (Halosulfuron methyl 5% + Atrazine 48% WG)
56.2 + 540
1125
5.66 {2.55} (96.36%)
12.33 {3.64} (93.42%)
1.66 {1.62} (64.38%)
3.66 {2.10} (35.34%)
0.00 {1.00} (100%)
2.00 {1.70} (71.83%)
2
DAH – 302 (Halosulfuron methyl 5% + Atrazine 48% WG)
62.5 + 600
1250
4.33 {2.26} (97.22%)
10.00 {3.29} (94.66%)
2.00 {1.69} (57.08%)
3.33 {2.04} (41.17%)
0.00 {1.00} (100%)
1.33 {1.52} (81.27%)
3
Halosulfuron methyl 75% WG
67.5
90
5.10 {2.44} (96.72%)
9.80 {3.26} (94.77%)
5.00 {2.42} (-7.20%)
5.10 {2.46} (9.89%)
3.00 {1.95} (48.28%)
3.10 {1.99} (56.34%)
4
Atrazine 50% WP
625
1250
140.70 {11.90} (9.61%)
180.40 {13.46} (3.60%)
1.90 {1.68} (59.23%)
2.10 {1.73} (62.80%)
2.10 {1.73} (63.79%)
2.10 {1.73} (70.42%)
5
Untreated Control
155.66 {12.51}
187.33 {13.72}
4.66 {2.34}
5.66 {2.53}
5.80 {2.58}
7.10 {2.83}
25
SEM (±)
{0.24}
{0.14}
{0.21}
{0.28}
{0.21}
{0.19}
CD 5%
{0.81}
{0.47}
N/A
N/A
{0.70}
{0.65}
Figures in parentheses {} are converted to √x+1 Figures in parentheses ( ) indicate percent weed control over untreated control DAT: Days after treatment ADVANTAGE OF THE INVENTION
[0080] The present disclosure provides a synergistic herbicidal composition that is free from the existing drawbacks of herbicidal compositions.
[0081] The present disclosure provides a synergistic herbicidal composition that is more effective than the compositions currently being used as herbicide.
[0082] The present disclosure provides a herbicidal composition that is synergistic and combines the therapeutic benefits of the individual herbicides i.e. Atrazine and Halosulfuron methyl in specific weight percentages along with at least one agrochemically acceptable excipient.
[0083] The present disclosure provides a process for the preparation of said herbicidal composition including effective amounts of Atrazine and Halosulfuron methyl.
[0084] The present disclosure provides a synergistic herbicidal composition that is specifically effective against sedges, narrow leaf weeds and broad leaf weeds in maize crop.
[0085] The present disclosure provides a synergistic herbicidal composition capable of providing high yield of maize crops.
[0086] The present disclosure provides a synergistic herbicidal composition having low toxicity towards non-target plants.
[0087] The present disclosure provides a synergistic herbicidal composition having lower undesirable effect on the environment.
[0088] The present disclosure provides a synergistic herbicidal composition having lower manufacturing and market costs compared to existing marketed compositions.
FOR DHANUKA AGRITECH LIMITED Tarun Khurana Regd. Patent Agent [INPA-1325] Dated: 02nd November,

We Claim:
1. A synergistic herbicidal composition comprising a combination of:
(a) Halosulfuron methyl in an amount of 5% by weight of the composition; (b) Atrazine in an amount of 48% by weight of the composition; and (c) at least one agrochemically acceptable excipient.
2. The synergistic herbicidal composition of claim 1, wherein the agrochemically acceptable excipient is a wetting agent selected from the group consisting of sulfosuccinates, naphthalene sulfonates, sulphated esters, phosphate esters, sulfated alcohol, alkyl benzene sulfonates and mixtures thereof.
3. The synergistic herbicidal composition of claim 1, wherein the agrochemically acceptable excipient is a dispersing agent selected from the group consisting of polycarboxylates, naphthalene sulfonate condensates, phenol sulfonic acid condensates, lignosulfonates, methyl oleyl taurates, polyvinyl alcohols and mixtures thereof.
4. The synergistic herbicidal composition of claim 1, wherein the agrochemically acceptable excipient is an emulsifier selected from the group consisting of ethoxylated and ethopropoxylated alcohols and nonyl phenols, ethoxylated tristeryl phenol, sodium lauryl sulphate, ethoxylated tristeryl phenol phosphates, ethoxylated and ethopropoxylated castor oil, calcium alkyl benzene sulfonates, proprietary blended emulsifiers and mixtures thereof.
5. The synergistic herbicidal composition of claim 1, wherein the agrochemically acceptable excipient is a filler selected from the group consisting of diatomaceous earth, China clay, kaolin, bentonite, precipitated silica, attapulgite, perlite and mixtures thereof.
6. The synergistic herbicidal composition of claim 1, wherein the agrochemically acceptable excipient is an anti foaming agent selected from the group consisting of silicon emulsion based anti foam agents, trisiloxane ethoxylates and mixtures thereof.
7. The synergistic herbicidal composition of claim 1, wherein the agrochemically acceptable excipient is a thickening agent selected from the group consisting of natural gums, resins, carboxy methyl cellulose and mixtures thereof.
8. The synergistic herbicidal composition of claim 1, wherein the synergistic herbicidal composition is in solid form.
9. The synergistic herbicidal composition of claim 1, wherein the composition is formulated as any of emulsion concentrates (EC), wettable powders (WP), suspoemulsions (SE), microemulsions, capsulated suspension, water dispersible granules (WG), ZC
27
composition, pellets, seed dressings or emulsions for seed treatment, broadcast granules, gel, emulsion in water or oil dispersions or combination thereof.
10. The synergistic herbicidal composition of claim 1, wherein the composition is in form of water dispersible granules (WG).
11. The synergistic herbicidal composition of claim 1, wherein the composition is applied to a plant by spraying, rubbing, dusting, pouring, mist blowing, soil mixing, dipping, drip irrigation or combination thereof.
12. The synergistic herbicidal composition of claim 1, wherein said composition exhibits herbicidal activity against sedges, narrows leaf weeds and broad leaf weeds.
13. The synergistic herbicidal composition of claim 1, wherein said composition exhibits herbicidal activity against sedges, narrow leaf weeds and broad leaf weeds in maize crop.
14. A process for preparing a synergistic herbicidal composition, said process comprising the steps of:
a) taking Halosulfuron methyl in an amount of 5% by weight of the composition;
b) mixing Atrazine in an amount of 48% by weight of the composition;
c) mixing at least one agrochemically acceptable excipient in an appropriate amount by weight of the composition in a homogenizer mixer;
d) milling the prepared mixture obtained in step (c) using a conventional mill to obtain an average particular size mill base; and
e) granulating the mill base in a conventional drier at a suitable temperature to obtain the synergistic herbicidal composition.
15. The process of claim 8, wherein the conventional mill as used in step (d) is selected from the group consisting of fluid energy mill, jet mill, pin mill and hammer mill.
16. The process of claim 8, wherein the conventional drier as used in step (e) is selected from the group consisting of spray drier and fluidized bed drier.
17. The process of claim 8, wherein the synergistic herbicidal composition is in form of water dispersible granules (WG).