FIELD OF THE INVENTION
[0001] The present disclosure relates to a synergistic herbicidal formulation comprising a combination of an ALS inhibitor and a triazinone herbicide. Specifically, it pertains to a herbicidal formulation for control of sedges, narrow and broad leaf weeds in sugarcane, comprising a combination of an effective amount of Halosulfuron methyl and an effective amount of Metribuzin in specific weight percentages along with at least one agrochemically acceptable excipient. The present invention further relates to a process for the preparation of formulation(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] Sugarcane is a tropical, perennial crop indigenous to tropical South and Southeast Asia. Its cultivation requires a tropical or temperate climate. Soil is a medium for its growth that provides nutrients, water and anchorage to the growing plants. So the maintenance of proper physical, chemical and biological conditions of the soil is necessary for realizing higher growth, yield and quality of sugarcane. Sugarcane crop remains 3-4 years in the same field. Therefore, all types of weeds, seasonal, annual and perennial grow in the field. These compete for nutrients, space, light and create a favorable environment for disease and insect development. Hence, sugarcane production is largely prone to weed infestation.
[0004] In sugarcane, weeds have been estimated to cause 12 to 72 % reduction in cane yield depending upon the severity of infestation. The nature of weed problem in sugarcane cultivation is quite different from other field crops on account of the following reasons: 1) Sugarcane is planted with relatively wider row spacing 2) The sugarcane growth is very slow in the initial stages. It takes about 30 - 45 days to complete germination and another 60-75 days for developing full canopy cover 3) The crop is grown under abundant water and nutrient supply conditions 4) In ratoon crop, very little preparatory tillage is taken up hence weeds that have established in the plant crop tend to flourish well.
[0005] Weeds of the sugarcane can be classified into three main groups i.e. sedges, broad leaves or dicotyledonous weeds and narrow leaves or grassy or monocotyledonous weeds. The sedges include Motha, Cyperus rotundus. The broad leaved weeds include Chenapodium album, Convolvulus
3
arvensis L., Amaranthus viridis L., Portulaca oleraceae L., Commelina bengalensis L., Trianthema portulacastrum L., etc. and the third group of grassy weeds, which are the most problematic, include Cyconodon doctylon, Echinochloa sp, Saccharum sp, etc.
[0006] The intensity of the weeds that infest sugarcane fields, right from planting to harvesting, depends on agro-climatic condition of the region. More crop-weed competition occurs during early phase of sugarcane growth. These weeds besides competing for moisture and light also remove about 4 times nitrogen and phosphorous and 2.5 times of potassium as compared to crop during the first 50-days period. They also harbor certain diseases and pests that attack sugarcane and lead to indirect losses. Thus, there is a pressing need for the synthesis of herbicidal formulations that can effectively control all the three types of weeds in sugarcane fields.
[0007] 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. It shows its action by inhibiting acetolactate synthase (ALS) enzyme.
[0008] Metribuzin with CAS registration number 21087-64-9, acts as herbicide by inhibiting photosynthesis by disrupting photosystem II. Its IUPAC name is 4-Amino-6-tert-butyl-3-methylsulfanyl-1, 2, 4-triazin-5-one.
[0009] WO2015078243 discloses combination of a triazinone herbicide and an ALS inhibitor herbicide. Though WO2015078243 discloses Metribuzin as one of the triazinone herbicide, which can be combined with a number of ALS inhibitors including Halosulfuron methyl, it does not disclose specific combination of Halosulfuron methyl and Metribuzin in any of the embodiments of its invention. It completely fails to disclose, teach, motivate or even suggest a person skilled in the art about synergistic effect obtainable by the combination of Halosulfuron methyl and Metribuzin. WO2012141277 discloses Halosulfuron methyl or Halosulfuron as one of the herbicides that can be mixed or may be used with the herbicidal composition comprising Flazasulfuron or its salt and Metribuzin or its salt. WO2012141277 also fails to disclose, teach, motivate or even suggest a person skilled in the art to utilize the specific combination of Halosulfuron methyl and Metribuzin and synergistic effect obtainable by combining them.
[0010] Presently, there are various herbicidal compositions that exist in the market which are used to fight with different variety of weeds infesting sugarcane crops. Most of these herbicidal compositions are not able to control sedges and all types of narrow and broad leaf weeds. This problem is not only faced by India but is also a matter of concern in many other parts of the world. This has led to constant efforts towards devising synergistic herbicidal compositions which are low cost, broad spectrum as well as environment friendly. Further, these herbicides are not able to control
4
sedges (Cyperus rotundus), which is a dreaded weed in Sugarcane cropping system due to presence of subterranean nuts.
[0011] There is therefore a need in the art to develop a new formulation which is free from the existing drawbacks of the formulations used as herbicide. Further agricultural field is in need of formulation having excellent 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 formulations, having herbicidal activity against broad-spectrum weeds. Thus, the present invention satisfies the existing needs, as well as others, and generally overcomes the deficiencies found in the existing art.
[0012] 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.
[0013] 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.
[0014] 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.
[0015] 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
5
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 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.
[0016] 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
[0017] An object of the present disclosure is to provide a synergistic herbicidal formulation including a combination of Halosulfuron methyl and Metribuzin, in specific weight percentages along with at least one agrochemically acceptable excipient.
[0018] Another object of the present disclosure is to provide a process for the preparation of a herbicidal formulation.
[0019] A further object of the present disclosure is to provide a synergistic herbicidal formulation effective against a wide variety of weeds in sugarcane fields.
[0020] A further object of the present disclosure is to provide a synergistic herbicidal formulation capable of providing high yield of sugarcane crops.
[0021] A further object of the present disclosure is to provide a synergistic herbicidal formulation capable of exhibiting long lasting effect.
[0022] A further object of the present disclosure is to provide a synergistic herbicidal formulation capable of exhibiting improved profitability for farmers.
[0023] A further object of the present disclosure is to provide a synergistic herbicidal formulation having low toxicity towards non-target plants.
[0024] A further object of the present disclosure is to provide a synergistic herbicidal formulation that is safe and cost-effective.
[0025] Yet another object of the present disclosure is to provide a synergistic herbicidal formulation having lower manufacturing and market costs as compared to existing marketed formulations.
[0026] Another object of the present disclosure is to provide a synergistic herbicidal formulation which obviates the disadvantages associated with known art.
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[0027] Another object of the present disclosure is to provide a synergistic herbicidal formulation which is inexpensive, dependable and fully effective in accomplishing its intended purposes.
[0028] Yet another object of the present disclosure is to provide a process that is technically and commercially feasible.
SUMMARY OF THE INVENTION
[0029] The present disclosure relates to a synergistic herbicidal formulation comprising a combination of an ALS inhibitor and a triazinone herbicide. Specifically, it pertains to a herbicidal formulation for control of sedges, narrow and broad leaf weeds in sugarcane, comprising a combination of an effective amount of Halosulfuron methyl and an effective amount of Metribuzin in specific weight percentages along with at least one agrochemically acceptable excipient. The present invention further relates to a process for the preparation of formulation(s) thereof.
[0030] An aspect of the present disclosure provides a synergistic herbicidal formulation including a combination of: (a) Halosulfuron methyl in an amount 6% by weight of the formulation; (b) Metribuzin in an amount 50% by weight of the formulation; and (c) at least one agrochemically acceptable excipient. In an embodiment, the formulation is in the form of solid or liquid. In an embodiment, the formulation is in the form of water dispersible granules (WG), suspension concentrates (SC), wettable powders (WP), emulsifiable concentrates (EC), granules, gel, suspo emulsions (SE), mixed formulation of capsule suspension and suspension concentrates (ZC) and the like and preferably, water dispersible granules (WG), suspo emulsions (SE) and mixed formulation of capsule suspension and suspension concentrates (ZC). In an embodiment, the formulation is applied by using any or a combination of spraying, rubbing, dusting, pouring, mist blowing, soil mixing, dipping, drip irrigation and other irrigation method. In an embodiment, the formulation is applied for protection and control of sedges, narrow and broad leaf weeds including, but not limited to, Cyperus rotundus, Echinochloa colonum and E. crusgalli (grasses), Dacryloctanum aegyptium (makra), Amaranthus viridis (cholai), Celosia argentia (safed murg), Cynodon dacrylon (doob), Sorghum halepense (banchari), Chenopodium album (bathua), Lathyrus sativa (matri), Vicia spp. (ankrni), Angallis arvensis (krishna Neel), Fumaria parviflora (gajri) and the like on sugarcane crops.
[0031] Another aspect of the present disclosure relates to a process for the preparation of a synergistic herbicidal formulation, said process including the steps of:
a) taking halosulfuron methyl in an amount of about 6% by weight of the formulation;
b) mixing metribuzin in an amount of about 50% by weight of the formulation with halosulfuron methyl;
c) mixing the at least one agriculturally acceptable excipient in an appropriate amount with a mixture including halosulfuron methyl and metribuzin in a homogenizer;
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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 formulation.
[0032] In an embodiment, the herbicidal formulation can be in the form of solid or liquid. In an embodiment, the formulation 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 formulation of capsule suspension and suspension concentrates (ZC) and the like and preferably, water dispersible granules (WG), suspo emulsions (SE) and mixed formulation of capsule suspension and suspension concentrates (ZC). In an embodiment, the herbicidal formulation 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 embodiment, the herbicidal formulation is applied for protection and control of sedges, narrow and broad leaf weeds such as Cyperus rotundus, Echinochloa colonum and E. crusgalli (grasses), Dacryloctanum aegyptium (makra), Amaranthus viridis (cholai), Celosia argentia (safed murg), Cynodon dacrylon (doob), Sorghum halepense (banchari), Chenopodium album (bathua), Lathyrus sativa (matri), Vicia spp. (ankrni), Angallis arvensis (krishna Neel), Fumaria parviflora (gajri) and the like on sugarcane crops.
DETAILED DESCRIPTION OF THE INVENTION
[0033] The present disclosure relates to a synergistic herbicidal formulation comprising a combination of an ALS inhibitor and a triazinone herbicide. Specifically, it pertains to a herbicidal formulation for control of sedges, narrow and broad leaf weeds in sugarcane, comprising a combination of an effective amount of Halosulfuron methyl and an effective amount of Metribuzin in specific weight percentages along with at least one agrochemically acceptable excipient. The present invention further relates to a process for the preparation of formulation(s) thereof.
[0034] 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.
[0035] 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.
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[0036] 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.
[0037] As used herein, the term “weed” refers to unwanted plant harmful to plant.
[0038] 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.
[0039] 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 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.
[0040] 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.
[0041] 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.
[0042] 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.
[0043] 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.
[0044] 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.
[0045] 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.
[0046] 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.
[0047] As used herein, “SE” refers to suspo-emulsion, which is a formulation containing both solid and liquid active ingredients dispersed in an aqueous phase.
[0048] 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.
[0049] As used herein, the term “agrochemical excipient” refers to an ingredient, additive, component or supplement, liquid or solid, suitable for incorporation in agricultural compositions.
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[0050] 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.
[0051] As used herein, the term “combination” refers to materials added together with or without substantial mixing towards achieving homogeneity.
[0052] As used herein, the term “mix” refers to adding materials together and achieving homogeneity, and the term “mixture” refers to mixed materials achieving homogeneity.
[0053] 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”.
[0054] 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.
[0055] An aspect of the present disclosure provides a synergistic herbicidal formulation including a combination of: (a) Halosulfuron methyl in an amount 6% by weight of the formulation; (b) Metribuzin in an amount 50% by weight of the formulation; and (c) at least one agrochemically acceptable excipient. In an embodiment, the formulation is in the form of solid or liquid. In an embodiment, the formulation is in the form of water dispersible granules (WG), suspension concentrates (SC), wettable powders (WP), emulsifiable concentrates (EC), granules, gel, suspo emulsions (SE), mixed formulation of capsule suspension and suspension concentrates (ZC) and the like and preferably, water dispersible granules (WG), suspo emulsions (SE) and mixed formulation of capsule suspension and suspension concentrates (ZC). In an embodiment, the formulation is applied by using any or a combination of spraying, rubbing, dusting, pouring, mist blowing, soil mixing, dipping, drip irrigation and other irrigation method. In an embodiment, the formulation is applied for protection and control of sedges, narrow and broad leaf weeds including, but not limited to, Cyperus rotundus, Echinochloa colonum and E. crusgalli (grasses), Dacryloctanum aegyptium (makra), Amaranthus viridis (cholai), Celosia argentia (safed murg), Cynodon dacrylon (doob), Sorghum halepense (banchari), Chenopodium album (bathua), Lathyrus sativa (matri), Vicia spp. (ankrni), Angallis arvensis (krishna Neel), Fumaria parviflora (gajri) and the like on sugarcane crops.
[0056] Another aspect of the present disclosure relates to a process for the preparation of a synergistic herbicidal formulation, said process including the steps of:
a) taking halosulfuron methyl in an amount of about 6% by weight of the formulation;
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b) mixing metribuzin in an amount of about 50% by weight of the formulation with halosulfuron methyl;
c) mixing the at least one agriculturally acceptable excipient in an appropriate amount with a mixture including halosulfuron methyl and metribuzin in a homogenizer;
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 formulation.
[0057] In an embodiment, the herbicidal formulation can be in the form of solid or liquid. In an embodiment, the formulation 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 formulation of capsule suspension and suspension concentrates (ZC) and the like and preferably, water dispersible granules (WG), suspo emulsions (SE) and mixed formulation of capsule suspension and suspension concentrates (ZC). In an embodiment, the herbicidal formulation 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 embodiment, the herbicidal formulation is applied for protection and control of sedges, narrow and broad leaf weeds such as Cyperus rotundus, Echinochloa colonum and E. crusgalli (grasses), Dacryloctanum aegyptium (makra), Amaranthus viridis (cholai), Celosia argentia (safed murg), Cynodon dacrylon (doob), Sorghum halepense (banchari), Chenopodium album (bathua), Lathyrus sativa (matri), Vicia spp. (ankrni), Angallis arvensis (krishna Neel), Fumaria parviflora (gajri) and the like on sugarcane crops.
[0058] In an embodiment, the formulation includes an appropriate amount of Halosulfuron methyl by weight of the composition. In an embodiment, the composition further includes an appropriate amount of Metribuzin by weight of the composition. In an embodiment, the formulation is capable of exhibiting synergistic herbicidal activity at much lesser amounts of Halosulfuron methyl and Metribuzin as compared to the amounts when used alone.
[0059] Surprisingly, it has been found that the herbicidal formulation of the present disclosure has superior weed control at lower levels of the combined specific concentrations of the active agents employed than that may be achieved when the active ingredients are applied alone. The two active ingredients exhibit synergistic effect when used in combination with each other.
[0060] In an embodiment, the formulation 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, antifoaming agent and stabilizers. However, those skilled in the art will appreciate that the additional agrochemically
11
acceptable excipients can be used without departing from the scope and spirit of the present disclosure. In another embodiment, the agrochemically acceptable excipient can be used in an appropriate range of the total weight of the present composition.
[0061] 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.
[0062] 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.
[0063] 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.
[0064] 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.
[0065] 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.
[0066] In an embodiment, the anti-foaming agent can be selected from silicon emulsion based anti foam agents, trisiloxane ethoxylates, etc.
[0067] In an embodiment, 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.
[0068] In an embodiment, the herbicidal formulation can be in the form of solid or liquid. In an embodiment, the herbicidal formulation can be prepared by various processes depending upon the composition types as known to a person skilled in the art.
[0069] In a preferred embodiment, a process used for preparation of a synergistic herbicidal formulation includes the steps of: taking halosulfuron methyl in an amount of about 6% by weight of the formulation; mixing metribuzin in an amount of about 50% by weight of the formulation with halosulfuron methyl; mixing the at least one agriculturally acceptable excipient in an appropriate amount with a mixture including halosulfuron methyl and metribuzin in a homogenizer; milling the prepared mixture 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
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formulation. However, a person skilled in the art would appreciate that any other conventional method can be utilized to prepare an advantageous synergistic herbicidal formulation without departing from the scope and spirit of the present invention. In a preferred embodiment, the conventional mill can be fluid energy mill, jet mill, pin mill, hammer mill and the like. In a preferred embodiment, the conventional drier can be spray drier, fluidized bed drier and the like.
[0070] In an embodiment, the mode of application of the synergistic herbicidal formulation is by using any one or a plurality of techniques including, but not limited to, spraying, rubbing, dusting, pouring, mist blowing, soil mixing, dipping and drip irrigation. 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.
[0071] In another preferred embodiment of the disclosure, the formulation 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.
[0072] In an embodiment, the amount of synergistic herbicidal formulation depends upon many factors including but not limited to type of formulations, the crop, weed sought to be controlled and environmental conditions.
[0073] 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 illustrations and not limitations.
[0074] While the foregoing describes various embodiments of the disclosure, other and further embodiments of the disclosure may be devised without departing from the basic scope thereof. The scope of the invention is determined by the claims that follow. The invention is not limited to the described embodiments, versions or examples, which are included to enable a person having ordinary skill in the art to make and use the invention when combined with information and knowledge available to the person having ordinary skill in the art.
EXAMPLES
[0075] Though, 2,4-D controls Cyperus rotundus by burning foliage, but the nuts/nutlets/ rhizomes present below the soil re-germinates after 10-15 days and start devouring nutrients. Attempts were made to find out the solution for the management of sedges (Cyperus rotundus), narrow leaf weeds and broad leaf weeds in Sugarcane simultaneously for a considerable period of time. A number of formulations with variable active ingredients composition of Halosulfuron Methyl and Metribuzin with number of surfactants and other adjuvants were prepared and evaluated to assess the bio-efficacy against sedges, narrow leaf weeds and broad leaf weeds in Sugarcane. The applications/spray
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treatments with different doses were made as pre and post-emergence. Based on the results, finally, a formulation containing Halosulfuron Methyl 6% + Metribuzin 50% WG was selected for further evaluation.
[0076] A combination formulation containing Halosulfuron Methyl 6% and Metribuzin 50% WG was evaluated at 1000 g/ha, 1125 g/ha and 1250 g/ha as pre-emergence and results as presented in table 1 to 4 below revealed that Halosulfuron Methyl and Metribuzin exhibits a strong synergistic efficacy at this particular concentration that recorded 87% to 92% control of sedges (Cyperus rotundus), 84% to 100% control of narrow leaf weeds and 100% control of broad leaf weeds after 21 to 78 days of treatment in different experiments, as against very poor control upon individual application of Halosulfuron Methyl and Metribuzin.
[0077] A strong synergy between Halosulfuron Methyl 6% and Metribuzin 50% was also observed when the formulation at 1250 g/ha was applied as post-emergence, which recorded 91% to 94% control of sedges (Cyperus rotundus), 97% to 100% control of narrow leaf weeds and 100% control of broad leaf weeds as presented in Table 5 to 7 below.
[0078] In both types of applications i.e. pre & post-emergence, Halosulfuron Methyl 75% WG and Metribuzin 70% WP alone recorded poor control of narrow leaf weeds and broad leaf weeds in comparison to pre-mix combination of Halosulfuron Methyl 6% and Metribuzin 50% WG, indicating that the combination has strong synergy for the effective control of sedges (Cyperus rotundus), narrow leaf weeds and broad leaf weeds.
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[0079] Table 1:- Effect of different herbicidal treatments on the weed flora of sugarcane applied as Pre –emergence
S. No
Treatments
a.i. (g/ha)
Formulation (g/ha)
Mean No. of weeds/0.25 sq.m.
Sedges
Narrow leaf weeds
Broad leaf weeds
20 DAT
40 DAT
20 DAT
40 DAT
20 DAT
40 DAT
1
DAH – 303 (Halosulfuron methyl 6% + Metribuzin 50%WG)
60 + 500
1000
7.33 {2.87} (69.87%)
12.33 {3.64} (63.00%)
0.00 {1.00} (100%)
8.33 {3.03} (59.68%)
0.00 {1.00} (100%)
2.00 {1.71} (64.66%)
2
DAH – 303 (Halosulfuron methyl 6% + Metribuzin 50% WG)
67.5 + 562.5
1125
5.33 {2.48} (78.09%)
6.33 {2.68} (81.01%)
0.00 {1.00} (100%)
8.00 {2.98} (61.28%)
0.00 {1.00} (100%)
0.33 {1.15} (94.17%)
3
DAH – 303 (Halosulfuron methyl 6% + Metribuzin 50% WG)
75 + 625
1250
4.33 {2.26} (82.20%)
4.33 {2.29} (87.01%)
0.00 {1.00} (100%)
0.00 {1.00} (100%)
0.00 {1.00} (100%)
0.00 {1.00} (100%)
4
Halosulfuron methyl 75% WG
67.5
90
4.70 {2.35} (80.68%)
3.60 {2.12} (89.10%)
15.40 {4.03} (11.70%)
19.30 {4.49} (6.58%)
2.40 {1.81} (48.40%)
3.10 {1.99} (45.23%)
5
Metribuzin 70% WP
525.5
750
23.60 {4.94} (3.00%)
30.30 {5.58} (9.09%)
1.10 {1.44} (93.77%)
2.10 {1.74} (89.84%)
3.10 {1.99} (33.48%)
3.40 {2.07} (39.93%)
6
Control (Untreated)
24.33 {5.02}
33.33 {5.85}
17.66 {4.31}
20.66 {4.64}
4.66 {2.33}
5.66 {2.55}
SEM (±)
{0.23}
{0.22}
{0.13}
{0.24}
{0.19}
{0.16}
CD 5%
{0.75}
{0.71}
{0.43}
{0.77}
{0.62}
{0.53}
Figures in parentheses {} are converted to √x+1 Figures in parentheses ( ) indicate percent weed control over control DAT: Days after treatment
15
[0080] Table 2:- Effect of different herbicidal treatments on the weed flora of sugarcane applied as Pre-emergence
Sl. No
Treatments
a.i. (g/ha)
Formulation (g/ha)
Mean No. of weeds/0.25 sq.m.
Sedges
Narrow leaf weeds
Broad leaf weeds
20 DAT
42 DAT
20DAT
42 DAT
20 DAT
42DAT
1
DAH – 303 (Halosulfuron methyl 6% + Metribuzin 50% WG)
60 + 500
1000
14.66 {3.95} (65.91%)
8.33 {3.03} (82.02%)
0.00 {1.00} (100%)
2.66 {1.90} (84.6%)
0.00 {1.00} (100%)
2.00 {1.71} (73.89%)
2
DAH – 303 (Halosulfuron methyl 6% + Metribuzin 50% WG)
67.5 + 562.5
1125
12.00 {3.60} (72.09%)
5.66 {2.55} (87.78%)
0.00 {1.00} (100%)
2.33 {1.81} (86.56%)
0.00 {1.00} (100%)
0.33 {1.14} (95.69%)
3
DAH – 303 (Halosulfuron methyl 6% + Metribuzin 50% WG)
75 + 625
1250
11.66 {3.55} (72.88%)
3.66 {2.15} (92.10%)
0.00 {1.00} (100%)
2.66 {1.89} (84.65%)
0.00 {1.00} (100%)
0.00 {1.00} (100%)
4
Halosulfuron methyl 75% WG
67.5
90
11.90 {3.57} (72.33%)
4.10 {2.25} (91.15%)
14.30 {3.90} (6.72%)
18.00 {4.35} (-3.87%)
3.10 {1.98} (45.23%)
3.50 {2.07} (54.31%)
5
Metribuzin 70% WP
525.5
750
42.10 {6.55} (2.09%)
44.70 {6.74} (3.52%)
0.00 {1.00} (100%)
5.30 {2.49} (69.42%)
2.60 {1.86} (54.06%)
3.40 {2.04} (55.61%)
6
Control (Untreated)
43.00 {6.62}
46.33 {6.87}
15.33 {4.03}
17.33 {4.26}
5.66 {2.56}
7.66 {2.92}
SEM (±)
{0.16}
{0.19}
{0.11}
{0.19}
{0.18}
{0.21}
CD 5%
{0.53}
{0.61}
{0.35}
{0.62}
{0.60}
{0.67}
Figures in parentheses {} are converted to √x+1 Figures in parentheses ( ) indicate percent weed control over control DAT: Days after treatment
16
[0081] Table 3:- Effect of different herbicidal treatments on the weed flora of sugarcane applied as Pre-emergence
Sl. No
Treatments
a.i. (g/ha)
Formulation (g/ha)
Mean No. of weeds/0.25 sq.m.
Sedges
Narrow leaf weeds
Broad leaf weeds
21DAT
21 DAT
21DAT
1
DAH – 303 (Halosulfuron methyl 6% + Metribuzin 50%WG)
67.5 + 562.5
1125
6.66 {2.74} (87.74%)
5.00 {2.42} (68.07%)
2.33 {1.81} (65.02%)
2
DAH – 303 (Halosulfuron methyl 6% + Metribuzin 50%WG)
75 + 625
1250
6.66 {2.70} (89.50%)
0.00 {1.00} (100%)
0.00 {1.00} (100%)
3
Halosulfuron methyl 75% WG
67.5
90
6.70 {2.75} (87.67%)
14.70 {3.94} (6.13%)
3.80 {2.16} (42.94%)
4
Metribuzin 70% WP
525.5
750
50.40 {7.16} (7.23%)
5.80 {2.55} (62.96%)
4.70 {2.34} (29.43%)
5
Control (Untreated)
54.33 {7.43}
15.66 {4.07}
6.66 {2.73}
SEM (±)
{0.07}
{0.30}
{0.24}
CD 5%
{0.26}
{1.01}
N/A
Figures in parentheses {} are converted to √x+1 Figures in parentheses ( ) indicate percent weed control over control DAT: Days after treatment
17
[0082] Table 4:- Effect of different herbicidal treatments on the weed flora of sugarcane applied as Pre-emergence
Sl. No
Treatments
a.i. (g/ha)
Formulation (g/ha)
Mean No. of weeds/0.25 sq.m.
Sedges
Narrow leaf weeds
Broad leaf weeds
38 DAT
78 DAT
38 DAT
78 DAT
38 DAT
78 DAT
1
DAH – 303 (Halosulfuron methyl 6% + Metribuzin 50% WG)
67.5 + 562.5
1125
7.33 {2.87} (69.87%)
2.66 {1.90} (88.43%)
10.00 {3.30} (77.79%)
0.00 {1.00} (100%)
1.66 {1.62} (90.04%)
0.00 {1.00} (100%)
2
DAH – 303 (Halosulfuron methyl 6% + Metribuzin 50% WG)
75 + 625
1250
7.00 {2.80} (71.23%)
2.00 {1.71} (91.30%)
0.00 {1.00} (100%)
0.00 {1.00} (100%)
2.00 {1.71} (88.00%)
0.00 {1.00} (100%)
3
Halosulfuron methyl 75% WG
67.5
90
6.70 {2.75} (72.46%)
1.90 {1.68} (91.74%)
40.70 {6.45} (3.00%)
51.60 {2.55} (0.77%)
9.70 {3.25} (41.78%)
15.40 {4.04} (53.79%)
4
Metribuzin 70% WP
525.5
750
23.60 {4.95} (3.00%)
22.80 {4.87} (0.87%)
7.10 {2.81} (83.10%)
1.70 {1.62} (96.73%)
2.60 {1.87} (84.39%)
1.60 {1.60} (95.20%)
5
Control (Untreated)
24.33 {5.02}
23.00 {4.89}
42.00 {6.55}
52.00 {7.27}
16.66 {4.19}
33.33 {5.85}
SEM (±)
{0.20}
{0.17}
{0.16}
{0.15}
{0.19}
{0.11}
CD 5%
{0.69}
{0.57}
{0.56}
{0.50}
{0.63}
{0.37}
Figures in parentheses {} are converted to √x+1 Figures in parentheses ( ) indicate percent weed control over control DAT: Days after treatment
18
[0083] Table 5:- Effect of different herbicidal treatments on the weed flora of sugarcane applied as Post-emergence
Sl. No.
Treatments
a.i. (g/ha)
Formulation (g/ha)
Mean No. of weeds/0.25 sq.m.
Sedges
Narrow leaf weeds
Broad leaf weeds
20 DAT
60 DAT
20 DAT
60 DAT
20 DAT
60 DAT
1
DAH – 303 (Halosulfuron methyl 6% + Metribuzin 50% WG)
67.5 + 562.5
1125
5.00 {2.43} (79.45%)
3.33 {2.06} (91.68%)
9.00 {3.15} (78.57%)
1.33 {1.51} (97.09%)
2.00 {1.74} (88.00%)
0.00 {1.00} (100%)
2
DAH – 303 (Halosulfuron methyl 6% + Metribuzin 50%WG)
75 + 625
1250
3.66 {2.14} (84.96%)
2.66 {1.90} (93.35%)
9.66 {3.24} (77.00%)
1.00 {1.41} (97.81%)
1.66 {1.62} (90.04%)
0.00 {1.00} (100%)
3
Halosulfuron methyl 75% WG
67.5
90
4.90 {2.40} (79.86%)
3.40 {2.09} (91.50%)
41.90 {2.40} (0.24%)
45.90 {6.84} (0.52%)
8.10 {3.00} (51.38%)
9.20 {3.18} (50.00%)
4
Metribuzin 70% WP
525.5
750
23.80 {4.97} (2.18%)
42.10 {6.56} (-5.25%)
8.70 {3.08} (79.29%)
9.10 {3.16} (80.07%)
7.30 {2.87} (56.18%)
8.10 {3.00} (55.98%)
5
Control
24.33 {5.03}
40.00 {6.39}
42.00 {6.55}
45.66 {6.82}
16.66 {4.19}
18.40 {4.39}
SEM (±)
{0.22}
{0.15}
{0.25}
{0.20}
{0.14}
{0.15}
CD 5%
{0.74}
{0.52}
{0.84}
{0.68}
{0.46}
{0.50}
Figures in parentheses {} are converted to √x+1 Figures in parentheses ( ) indicate percent weed control over control DAT: Days after treatment
19
[0084] Table 6:- Effect of different herbicidal treatments on the weed flora of sugarcane applied as Post-emergence
Sl. No
Treatments
a.i. (g/ha)
Formulation (g/ha)
Mean No. of weeds/0.25 sq.m.
Sedges
Narrow Leaf Weeds
Broad Leaf Weeds
20 DAT
50 DAT
20 DAT
50 DAT
20 DAT
50 DAT
1
DAH – 303 (Halosulfuron methyl 6% + Metribuzin 50% WG)
60 + 500
1000
8.33 {3.04} (89.32%)
9.66 {3.24} (89.27%)
0.33 {1.15} (94.17%)
0.00 {1.00} (100%)
0.00 {1.00} (100%)
0.00 {1.00} (100%)
2
DAH – 303 (Halosulfuron methyl 6% + Metribuzin 50% WG)
67.5 + 562.5
1125
7.00 {2.79} (91.03%)
7.33 {2.86} (91.86%)
0.33 {1.15} (94.17%)
0.00 {1.00} (100%)
0.00 {1.00} (100%)
0.00 {1.00} (100%)
3
DAH – 303 (Halosulfuron methyl 6% + Metribuzin 50% WG)
75 + 625
1250
6.66 {2.74} (91.46%)
4.66 {2.34} (94.82%)
0.33 {1.15} (94.17%)
0.00 {1.00} (100%)
0.00 {1.00} (100%)
0.00 {1.00} (100%)
4
Halosulfuron methyl 75% WG
67.5
90
6.70 {2.75} (91.41%)
3.90 {2.18} (95.67%)
4.70 {2.35} (16.96%)
8.10 {2.98} (-10.50%)
3.70 {2.12} (26.00%)
4.90 {2.40} (30.99%)
5
Metribuzin 70% WP
525.5
750
80.00 {8.99} (-2.56%)
89.40 {9.50} (0.67%)
0.70 {1.29} (87.63%)
2.40 {1.81} (67.22%)
3.10 {1.99} (38.00%)
3.40 {2.08} (52.11%)
6
Control
78.00 {8.88}
90.00 {9.53}
5.66 {2.55}
7.33 {2.84}
5.00 {2.43}
7.10 {2.81}
SEM (±)
{0.18}
{0.19}
{0.14}
{0.22}
{0.16}
{0.15}
CD 5%
{0.58}
{0.62}
{0.46}
{0.71}
{0.52}
{0.50}
Figures in parentheses {} are converted to √x+1 Figures in parentheses ( ) indicate percent weed control over control DAT: Days after treatment
20
[0085] Table 7:- Effect of different herbicidal treatments on the weed flora of sugarcane applied as Post-emergence
Sl. No
Treatments
a.i. (g/ha)
Formulation (g/ha)
Mean No. of weeds/0.25 sq.m.
Sedges
Narrow Leaf Weeds
Broad Leaf Weeds
20 DAT
50 DAT
20 DAT
50 DAT
20 DAT
50 DAT
1
DAH – 303 (Halosulfuron methyl 6% + Metribuzin 50%WG)
60 + 500
1000
9.33 {3.20} (86.92%)
17.33 {4.27} (76.99%)
0.33 {1.51} (94.10%)
0.00 {1.00} (100%)
0.00 {1.00} (100%)
0.00 {1.00} (100%)
2
DAH – 303 (Halosulfuron methyl 6% + Metribuzin 50%WG)
67.5 + 562.5
1125
9.00 {3.13} (87.38%)
11.66 {3.54} (84.52%)
0.33 {1.14} (94.10%)
0.00 {1.00} (100%)
0.00 {1.00} (100%)
0.00 {1.00} (100%)
3
DAH – 303 (Halosulfuron methyl 6% + Metribuzin 50%WG)
75 + 625
1250
8.00 {2.98} (88.78%)
6.66 {2.74} (91.16%)
0.33 {1.15} (94.10%)
0.00 {1.00} (100%)
0.00 {1.00} (100%)
0.00 {1.00} (100%)
4
Halosulfuron methyl 75% WG
67.5
90
8.40 {3.04} (88.22%)
5.90 {2.62} (92.16%)
7.10 {2.81} (-18.33%)
8.50 {3.08} (-4.93%)
2.50 {1.87} (46.35%)
2.90 {1.97} (43.13%)
5
Metribuzin 70% WP
525.5
750
70.30 {8.44} (1.44%)
72.20 {8.55} (4.12%)
0.50 {1.22} (91.67%)
1.20 {1.47} (85.19%)
1.10 {1.44} (76.39%)
2.80 {1.93} (45.10%)
6
Control
71.33 {8.50}
75.30 {8.73}
6.00 {2.62}
8.10 {2.99}
4.66 {2.34}
5.10 {2.45}
SEM (±)
{0.20}
{0.18}
{0.16}
{0.13}
{0.11}
{0.18}
CD 5%
{0.65}
{0.57}
{0.53}
{0.43}
{0.37}
{0.60}
Figures in parentheses {} are converted to √x+1 Figures in parentheses ( ) indicate percent weed control over control DAT: Days after treatment
21
ADVANTAGES OF THE INVENTION
[0086] The present disclosure provides for a synergistic herbicidal formulation including a combination of Halosulfuron methyl and Metribuzin, in specific weight percentages along with at least one agrochemically acceptable excipient.
[0087] The present disclosure provides for a process for the preparation of said herbicidal composition.
[0088] The present disclosure provides for a synergistic herbicidal composition effective against a wide variety of weeds in sugarcane fields.
[0089] The present disclosure provides for a synergistic herbicidal formulation capable of providing high yield of sugarcane crops.
[0090] The present disclosure provides for a control of dreaded weed, Cyperus rotundus.
[0091] The present disclosure provides for application of synergistic herbicide formulation as pre-emergence, i.e. before germination of Sugarcane and weeds.
[0092] The present disclosure provides for application of synergistic herbicidal formulation as post-emergence i.e., after germination of Sugarcane and weeds.
[0093] The present disclosure provides a synergistic formulation which is non-phytotoxic to crop.
[0094] The present disclosure provides a synergistic formulation which acts as a plant growth regulator and enhances the cane yield.
[0095] The present disclosure provides for a synergistic herbicidal formulation capable of exhibiting long lasting effect.
[0096] The present disclosure provides for a synergistic herbicidal formulation capable of exhibiting improved profitability for farmers.
[0097] The present disclosure provides for a synergistic herbicidal formulation having no toxicity towards non-target plants.
[0098] The present disclosure provides for a synergistic herbicidal formulation that is safe and cost-effective.
[0099] The present disclosure provides for a synergistic herbicidal formulation having lower manufacturing, market cost and application cost as compared to existing marketed formulations.
[00100] The present disclosure provides for a synergistic herbicidal formulation which obviates the disadvantages associated with known art.
[00101] The present disclosure provides for a synergistic herbicidal formulation which is inexpensive, dependable and fully effective in accomplishing its intended purposes.
22
[00102] The present disclosure provides for a process for preparation of a synergistic herbicidal formulation that is technically and commercially feasible.

We Claim:
1. A synergistic herbicidal formulation comprising a combination of:
(a) Halosulfuron methyl in an amount 6% by weight of the formulation; (b) Metribuzin in an amount 50% by weight of the formulation; and (c) at least one agrochemically acceptable excipient.
2. The formulation as claimed in claim 1, wherein said formulation is in a solid form or a liquid form.
3. The formulation as claimed in claim 1, wherein said formulation is in form of any of water dispersible granule (WG), suspension concentrate (SC), wettable powder (WP), emulsifiable concentrate (EC), granule, gel, suspo emulsion (SE), mixed formulation of capsule suspension and suspension concentrate (ZC).
4. The formulation as claimed in claim 1, wherein said formulation is in form of water dispersible granule (WG).
5. The formulation as claimed in claim 1, wherein said formulation is applied by using any or a combination of spraying, rubbing, dusting, pouring, mist blowing, soil mixing, dipping and drip irrigation.
6. The formulation as claimed in claim 1, wherein said formulation affords control of any or a combination of sedges, narrow leaf weeds and broad leaf weeds selected from a group consisting of Cyperus rotundus, Echinochloa colonum and E. crusgalli (grasses), Dacryloctanum aegyptium (makra), Amaranthus viridis (cholai), Celosia argentia (safed murg), Cynodon dacrylon (doob), Sorghum halepense (banchari), Chenopodium album (bathua), Lathyrus sativa (matri), Vicia spp. (ankrni), Angallis arvensis (krishna Neel) and Fumaria parviflora (gajri) on sugarcane crop.
7. A process for preparation of a synergistic herbicidal formulation, said process comprising the steps of:
a) taking halosulfuron methyl in an amount of about 6% by weight of the formulation;
b) mixing metribuzin in an amount of about 50% by weight of the formulation with halosulfuron methyl;
c) mixing at least one agriculturally acceptable excipient in an appropriate amount with the mixture including halosulfuron methyl and metribuzin in a homogenizer;
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 formulation.
24
8. The process as claimed in claim 7, wherein said formulation is in a solid form or a liquid form.
9. The process as claimed in claim 7, wherein said formulation is in form of any of water dispersible granule (WG), suspension concentrate (SC), wettable powder (WP), emulsifiable concentrate (EC), granule, gel, suspo emulsion (SE), mixed formulation of capsule suspension and suspension concentrate (ZC).
10. The process as claimed in claim 7, wherein said formulation is in form of water dispersible granule (WG).
11. The process as claimed in claim 7, wherein said formulation is applied by using any or a combination of spraying, rubbing, dusting, pouring, mist blowing, soil mixing, dipping and drip irrigation.
12. The process as claimed in claim 7, wherein said formulation affords control of any or a combination of sedges, narrow leaf weeds and broad leaf weeds selected from a group consisting of Cyperus rotundus, Echinochloa colonum and E. crusgalli (grasses), Dacryloctanum aegyptium (makra), Amaranthus viridis (cholai), Celosia argentia (safed murg), Cynodon dacrylon (doob), Sorghum halepense (banchari), Chenopodium album (bathua), Lathyrus sativa (matri), Vicia spp. (ankrni), Angallis arvensis (krishna Neel) and Fumaria parviflora (gajri) on sugarcane crop.