Claims:1. A synergistic herbicidal composition comprising:
a. ethyl 2-[(4-chloro-6-methoxypyrimidin-2-yl)carbamoylsulfamoyl]benzoate;
b. 4-amino-6-tert-butyl-4,5-dihydro-3-methylthio-1,2,4-triazin-5-one; and
c. at least one derivative of 2,4-dichlorophenoxyacetic acid.

2. The composition as claimed in claim 1, wherein said derivative is a salt selected from the group consisting of sodium, potassium, lithium, ammonium, dimethylamine, diethylamine, triethylamine, isopropylamine salt, and combinations thereof.

3. The composition as claimed in claim 1, wherein said derivative is an ester.

4. The composition as claimed in claim 3, wherein said ester is an alkyl ester selected from the group consisting of methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, 2-ethylhexyl, octyl, isooctyl ester, and combinations thereof.

5. The composition as claimed in any of the claims 1 to 4, wherein ethyl 2-[(4-chloro-6-methoxypyrimidin-2-yl)carbamoylsulfamoyl]benzoate w/w concentration in said composition is in the range of 0.2% to 2%, 4-amino-6-tert-butyl-4,5-dihydro-3-methylthio-1,2,4-triazin-5-one w/w concentration in said composition is in the range of 10% to 60%, and at least one derivative of 2,4-dichlorophenoxyacetic acid w/w concentration in said composition is in the range of 20% to 60%.

6. The composition as claimed in claim 5, wherein ethyl 2-[(4-chloro-6-methoxypyrimidin-2-yl)carbamoylsulfamoyl]benzoate w/w concentration in said composition is 0.8%, 4-amino-6-tert-butyl-4,5-dihydro-3-methylthio-1,2,4-triazin-5-one w/w concentration in said composition is 32%, and at least one derivative of 2,4-dichlorophenoxyacetic acid w/w concentration in said composition is 48%.

7. The composition as claimed in any of the claims 1 to 6 further comprising:
a. at least one dispersing agent;
b. at least one wetting agent;
c. at least one surfactant; and
d. at least one antifoaming agent.

8. The composition as claimed in claim 7, optionally further comprising at least one filler, and at least one binder.

9. The composition as claimed in any of the claims 7 and 8, wherein said at least one dispersing agent, at least one wetting agent, at least one surfactant, at least one antifoaming agent, at least one filler, and at least one binder are known in the art, and suitable for said herbicidal composition.

10. A granular formulation comprising a composition as claimed in any of the claims 1 to 9.

11. The composition as claimed in any of the claims 1-9 or the formulation as claimed in claim 10, wherein said composition or formulation is applied in an amount ranging from 200g/ha to 5000 g/ha of ethyl 2-[(4-chloro-6-methoxypyrimidin-2-yl)carbamoylsulfamoyl]benzoate, 4-amino-6-tert-butyl-4,5-dihydro-3-methylthio-1,2,4-triazin-5-one, and at least one derivative of 2,4-dichlorophenoxyacetic acid.

12. The composition or the formulation as claimed in claim 11, wherein said composition or formulation is applied in an amount ranging from 300g/ha to 4000g/ha of ethyl 2-[(4-chloro-6-methoxypyrimidin-2-yl)carbamoylsulfamoyl]benzoate, 4-amino-6-tert-butyl-4,5-dihydro-3-methylthio-1,2,4-triazin-5-one, and at least one derivative of 2,4-dichlorophenoxyacetic acid.

13. A method of controlling undesirable vegetation comprising:
a. obtaining a composition as claimed in any of the claims 1 to 9 or a formulation as claimed in claim 10; and
b. applying an effective amount of said composition or formulation to control said undesirable vegetation.

14. The method as claimed in claim 13, wherein said undesirable vegetation is a weed selected from the group consisting of monocotyledonous or grassy weeds, dicotyledonous or broad leaf weeds, sedges, and combinations thereof.

15. The method as claimed in claim 13, wherein said composition or formulation can be applied at pre-emergence to prevent germination of weeds or post emergence to control growing of harmful weeds.
, Description:FIELD OF THE INVENTION
[0001] The present invention relates to a ternary herbicidal composition and a method of use for controlling unwanted vegetation in cultivated crop plants. More particularly, the present invention relates to a herbicidal composition in solid formulation comprising a) ethyl 2-[(4-chloro-6-methoxypyrimidin-2-yl)carbamoyl sulfamoyl] benzoate; b) 4-amino-6-tert-butyl-4,5-dihydro-3-methylthio-1,2,4-triazin-5-one; and c) at least one derivative of 2,4-dichlorophenoxyacetic acid, which provides synergistic control of harmful weeds in cultivated crop plants and non-cropped area.

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] Weeds adversely impact on a sugarcane and other crop plants in a number of ways. A significant reduction in yield and its quality occurs if weeds are not controlled, as they compete with the cultivated crop for nutrients, sunlight and moisture. Other weeds, such as vines, climb over and entangle themselves with the sugarcane crop, making harvesting difficult and reducing product quality. Some weeds may also release compounds that are toxic to sugarcane growth. Sugarcane being a long duration and widely spaced (60 to 90 cm row distance) crop provides an ample opportunity for several weeds species to grow in the vacant spaces, right from planting to harvesting. To help combat this problem, researchers in the field of synthetic chemistry have produced an extensive variety of chemicals and chemical formulations effective in the control of such unwanted plants called weeds. Chemical herbicides of many types have been disclosed in the literature and a large number are in commercial use.
[0004] In recent years, a number of chemicals having herbicidal activity have been used to control weeds in sugarcane fields. The most commonly used herbicides in sugarcane fields to manage the weeds are ametryn, atrazine, simazine, alachlor, metolachlor, S-metolachlor, asulam, metribuzin, trifluralin, pendimethalin, tebuthiuron, diuron, hexazinone, amicarbazone, imazapic, trifloxysulfuron-sodium, iodosulfuron-methyl-sodium, halosulfuron-methyl, ethoxysulfuron, carfentrazone-ethyl, isoxaflutole, bicyclopyrone, mesotrione, picloram and its salts and esters thereof, 2,4-D and its salts and esters thereof, dicamba and its salts and esters thereof, clomazone, MSMA, paraquat, diquat, glufosinate and salts thereof, glufosinate-P and salts thereof, and glyphosate and salts thereof. Since weeds are diversified in kind viz. grassy weeds, broad leaf weeds, sedges and vines, and their emergence extends over a long period of time, the herbicidal effects of conventional single herbicidal agents are restricted in general as most of the available herbicides can control either one type of weed i.e. either grassy weeds or broad leaf weeds, having affectivity when apply before germination of weeds or after germination of weeds. Some of the weed species like Commelina spp., Ipomoea spp, Solanum nigrum, Xanthium spp., among broad leaf weeds, Cyprus rotundus among sedges and Eleusine indica, Dactyloctenium aegyptium, Brachiaria spp. among grassy weeds in sugarcane crop are difficult to kill by singly or even mixtures of two herbicidal active ingredients. Moreover, most of the herbicides do not protect the germination of weeds after killing of standing weeds, therefore new weeds again emerge out and start competing with the cultivated crop plants. In view of such situation, it is desirable to develop a herbicidal composition having broad herbicidal activity spectrum against a wide variety of weeds and a long residual effect to prevent subsequent germination of weeds without any phytotoxicity to the crop plants.
[0005] Compositions of herbicidal combinations offer significant advantages over individual applications including improved and extended weed control, reduced herbicide rates and application costs, shorter contact times for improved results in flowing water, less stringent use restrictions, improved selectivity, improved spectrum of weeds controller reduced cost and reduced residue problems. In some cases, the herbicidal active ingredients have been shown to be more effective in combination than when applied individually. However, identifying appropriate herbicide combinations having chemical and physical stability while combining two or three herbicidal actives remains a challenge.
[0006] In contrast, it is more sensible to be able to employ herbicidal combinations which have proven sufficiently effective and able to control multiple types of weeds for as long as possible, especially when it has shown itself to be environmentally compatible to a particularly high degree and to possess only minimal side-effects.
[0007] Ethyl 2-[(4-chloro-6-methoxypyrimidin-2-yl)carbamoylsulfamoyl] benzoate, generally called as Chlorimuron ethyl is a herbicide that inhibits acetolactate synthase (ALS). It belong to sulfonylurea chemistry and can be used for post-emergence control of important broadleaf weeds, such as cocklebur, pigweed, sunflower, annual morning glory and other broadleaf weeds in soybeans and rice at extremely very low application rates . Its herbicidal activity is described in book entitled ‘The Pesticide Manual’, seventeenth Edition, 2015, page-186.
[0008] 4-Amino-6-tert-butyl-4,5-dihydro-3-methylthio-1,2,4-triazin-5-one, generally called as Metribuzin is a triazinone herbicide that inhibits photosynthesis in a susceptible plant by binding to a protein of the photosystem II complex and it is used as a pre-plant incorporated, pre-emergence, and post-emergence herbicide to control many broad-leaf and narrow-leaf weed species in several crops, including alfalfa, sugarcane, potatoes, and soybeans. Its herbicidal activity is described in book entitled ‘The Pesticide Manual’, seventeenth Edition, 2015, page-769.
[0009] 2,4-Dichlorophenoxyacetic acid, generally called as 2,4-D is herbicide that kills the plant by mimicking auxin, a plant growth hormone and it is used as herbicide in form of agriculturally acceptable salts or esters thereof to control broadleaf weeds in, for instance, wheat, cereals, corn, grasses, rice, sorghum, sugarcane, fallow land, pasture, rangeland, turf, and non-cropland as post-emergent application. Its herbicidal activity is described in book entitled ‘The Pesticide Manual’, seventeenth Edition, 2015, page-283.
[00010] WO2013/089207 discloses a method for controlling weeds in a sugar cane field. The method involves the use of at least one herbicide selected from ametryn, atrazine, simazine, alachlor, metolachlor, S-metolachlor, asulam, metribuzin , trifluralin, pendimethalin, tebuthiuron, diuron, hexazinone, amicarbazone, imazapic, trifloxysulfuron sodium salt, iodosulfuron-methyl sodium salt, halosulfuron-methyl, ethoxysulfuron, carfentrazone-ethyl, isoxaflutole, bicyclopyrone, mesotrione, picloram and its salts and esters thereof, 2,4-D and its salts and esters thereof, dicamba and its salts and esters thereof, clomazone, MSMA, parachor, diquat, glufosinate, glufosinate ammonium salt, glufosinate-P and salts thereof, and glyphosate and salts thereof.
[00011] WO2010/000365 or EP2296468 discloses a method of selectively controlling unwanted vegetation at a locus comprising sugarcane and the unwanted vegetation, wherein the method comprises applying (a) a herbicide, chemically “4-hydroxy-3-({2-[(2-methoxyethoxy)methyl]-6-(trifluoromethyl)pyridin-3-yl}carbonyl)bicyclo[3.2.1]oct-3-en-2-one” or an agro chemically acceptable salt thereof; and (b) a PS-II inhibiting herbicide; wherein the amount of component (a) and component (b) applied to the locus provides control of the unwanted vegetation and wherein the amount of component (b) applied safens the herbicidal effect of component (a) on the sugarcane. The invention further provides a herbicide composition comprising (a) a herbicide of formula (I) or an agro chemically acceptable salt thereof; and (b) a herbicide selected from the group consisting of metribuzin, hexazinone and tebuthiuron.
[00012] WO2015/044150 discloses a methods for controlling weeds in sugar cane plantations, wherein at least one herbicide (A) is applied as solid agrochemical formulation (B) to the plantation; and solid agrochemical formulations (B), which are dry, ready for use granules, comprising at least one herbicide (A) selected from metribuzin, diuron, bentazone, hexazinone, tebuthiuron, sulfentrazone, imazapic, imazapyr, glyphosate, MSMA, ametryn, clomazone, isoxaflutole, mesotrione, amicarbazone, atrazine, paraquat, 2,4-D, pendimethalin, saflufenacil and 1,5-dimethyl-6-thioxo-3-(2,2,7-trifluoro-3-oxo-4-(prop-2-ynyl)-3,4-dihydro-2H-benzo[b] [1,4]oxazin-6-yl)-1,3,5-triazinane-2,4-dione and at least one carrier (C) selected from the groups (C1) to (C7): (C1) organic based materials (botanicals); (C2) fertilizers; (C3) clays; (C4) carbonates; (C5) sulfates; (C6) synthetic of synthetically modified minerals; (C7) synthetic polymers, polymer dispersions and superabsorbent polymers.
[00013] CN104970026 A discloses a herbicidal composition, containing 1 part by weight of isooctyl (2,4-dichlorophenoxy)acetate, 0.01-90 parts by weight of 4-amino-6-tert-butyl-4,5-dihydro-3-methylthio-1,2,4-triazin-5-one and 0.05-50 parts by weight of metolachlor. The invention also provides application of the above herbicidal composition in the prevention and control of weeds in crops. Through the above technical solution, the herbicidal composition of the present invention can achieve significant synergic control effect, thus improving the performance of the herbicide.
[00014] US8,921,271 discloses a herbicidal composition comprising, as active ingredients, (a) flazasulfuron or its salt and (b) 4-amino-6-tert-butyl-4,5-dihydro-3-methylthio-1,2,4-triazin-5-one or its salt. 2,4-D is also disclosed as an additional herbicide.
[00015] Raskar, B.S. (2004). Evaluation of herbicides for weed control in sugarcane. Sugar Tech Volume 6, Issue 3, pp 173–175 discloses significant reduction in weed density and weed dry matter at 120 days after planting was obtained with pre-emergence application of metribuzin 1.5 kg/ha supplemented with post emergence application of sodium (2,4-dichlorophenoxy) acetate salt 1 kg/ha.
[00016] Kumar Rajender, Singh Jayesh and Uppal S.K. (2014). Weed management in sugarcane ratoon crop. Indian Journal of Weed Science 46(4): 346–349 also disclosed the significant dry weight reduction of weeds to less than one third (54.3 g/m2) with pre-emergence application of 4-amino-6-tert-butyl-4,5-dihydro-3-methylthio-1,2,4-triazin-5-one 1.4 kg/ha fb 2,4-D 1.6 kg/ha at 45 DARI compared to weedy check.
[00017] However, none of the aforementioned publications contemplate combinations of three herbicidal active substance involving a combination of ethyl 2-[(4-chloro-6-methoxypyrimidin-2-yl)carbamoyl sulfamoyl] benzoate, 4-amino-6-tert-butyl-4,5-dihydro-3-methylthio-1,2,4-triazin-5-one, and 2,4-dichlorophenoxyacetic acid in the form of salt or ester exemplified together.
[00018] ethyl 2-[(4-chloro-6-methoxypyrimidin-2-yl)carbamoyl sulfamoyl] benzoate, 4-amino-6-tert-butyl-4,5-dihydro-3-methylthio-1,2,4-triazin-5-one, and 2,4-dichlorophenoxyacetic acid in the form of salt or ester are well known herbicides that shares common characteristic, such as e.g. a remarkable and good activity on broad leaved weeds when use as pre and post emergent application. In addition, all these herbicide, more particularly 4-amino-6-tert-butyl-4,5-dihydro-3-methylthio-1,2,4-triazin-5-one, and 2,4-dichlorophenoxyacetic acid in the form of salt or ester have been used in combined applications as tank mix with at least one other commonly used sugarcane herbicide. However, effectiveness of such combinations is often not satisfactory and high application rate are still required to achieve an acceptable control of a broad spectrum of weeds. In addition, the herbicidal activity of these compositions often persists only for a short time, which allows effective burn down only within a small timeframe of limited type of weeds and chances are very high to escaping certain difficult to control weed species.
[00019] In general, however, there remains a need for provides a herbicidal combination, which allows efficient and accelerated control of broad spectrum weeds which includes monocotyledons or grassy weeds, dicotyledons or broad leaf weeds and sedges in comparison with application of the individual herbicides. Moreover, the persistence of the herbicidal activity of the combination should be sufficiently long in order to achieve control of the weeds over a sufficient long time period thus allowing a more flexible application. The combination should also have a low toxicity to humans or other mammals and environment. The combinations should also show an accelerated action on harmful plants, i.e. they should effect damaging of the harmful with a lower application rate of active compounds. In addition, the combinations reduce the economic input and improve the ecological compatibility of the herbicide treatment. However, while formulating two or more herbicides in a single composition, a formulator is faced by many problems such as physical and biological incompatibility, a lack of stability in a co-formulation, decomposition of an active compound, or antagonism of the active compounds.
[00020] Therefore there is always a need in the art, a better combination of herbicidal active compounds having an advantageous activity profile, high stability and, a synergistically improved action, which allows the application rate to be reduced in comparison with the individual application of the active compounds to be combined.

OBJECTS OF THE INVENTION
[00021] Accordingly, it is an object of the present invention is to provide a herbicidal composition, which comprises a synergistically herbicidal effective amount of a) ethyl 2-[(4-chloro-6-methoxypyrimidin-2-yl)carbamoyl sulfamoyl] benzoate (hereinafter referred to as Herbicide-A); b) 4-amino-6-tert-butyl-4,5-dihydro-3-methylthio-1,2,4-triazin-5-one (hereinafter referred to as Herbicide-B) and c) at least one derivative of 2,4-dichlorophenoxyacetic acid (hereinafter referred to as Herbicide-C).
[00022] In another object of the present invention, the derivative of 2,4-dichlorophenoxy acetic acid is a salt thereof selected from the group consisting of sodium, potassium, lithium, ammonium, dimethylamine, diethylamine, triethylamine, isopropylamine, and combinations thereof.
[00023] In another object of the present invention, the derivative of 2,4-dichlorophenoxy acetic acid is an ester thereof, wherein said ester is an alkyl ester selected from the group consisting of methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, 2-ethylhexyl, octyl, isooctyl ester, and combinations thereof.
[00024] Yet another object of the present invention is to provide a herbicidal composition which is highly effective on broad range of weeds species in sugarcane crop.
[00025] Yet another object of the present invention is to provide a herbicidal composition which controls the weeds for a long duration.
[00026] Yet another object of the present invention is to provide a herbicidal composition which is selective for sugarcane crop.
[00027] Another object of the present invention is to provide a method for preparation of a homogenous composition of herbicide in dry form such as wettable powder, wettable granule, water dispersible granule, and dry flowable.
[00028] Still another object of the present invention is to provide a herbicidal composition which can control weed at pre-emergent or post emergent stage.
[00029] Another object of the present invention is to provide a herbicidal composition which is highly effective against hard to kill weeds in sugarcane crop fields, especially weeds such as Commelina spp,. Ipomoea spp, Solanum nigrum, Xanthium spp., among broad leaf weeds, Cyprus rotundus among sedges and Eleusine indica, Dactyloctenium aegyptium, Brachiaria spp among grassy weeds.
[00030] The other objects and preferred embodiments and advantages of the present invention will become more apparent from the following description of the present invention when read in conjunction with the accompanying examples and figures, which are not intended to limit scope of the present invention in any manner.
[00031] Other objects and advantages of the present invention will be more apparent from the following description, which is not intended to limit the scope of the present disclosure.

SUMMARY OF THE INVENTION
[00032] In an aspect of the present invention, there is provided a ternary herbicidal composition which is useful for controlling undesired weeds in cultivated crop plants particularly sugarcane. More particularly, the present invention relates to a herbicidal composition comprising a synergistically herbicidal effective amount of a) ethyl 2-[(4-chloro-6-methoxypyrimidin-2-yl)carbamoyl sulfamoyl] benzoate (Herbicide-A); b) 4-amino-6-tert-butyl-4,5-dihydro-3-methylthio-1,2,4-triazin-5-one (Herbicide-B) and c) at least one derivative of 2,4-dichlorophenoxyacetic acid (Herbicide-C). The composition may also contain an agriculturally acceptable adjuvant or carrier formulated in dry form.

BRIEF DESCRIPTION OF THE DRAWINGS
[00033] The accompanying drawings are included to provide a further understanding of the present disclosure, and are incorporated in and constitute a part of this specification. The drawings illustrate exemplary embodiments of the present disclosure and, together with the description, serve to explain the principles of the present disclosure.
[00034] Figure 1 depicts the time dependent synergistic effect of a herbicidal composition of herbicide A, B, and C at a particular ratio in contrast to individual herbicides on control of grassy weeds in sugarcane fields.
[00035] Figure 2 depicts the time dependent synergistic effect of a herbicidal composition of herbicide A, B, and C at a particular ratio in contrast to individual herbicides on control of broad leaf weeds in sugarcane fields.
[00036] Figure 3 depicts the time dependent synergistic effect of a herbicidal composition of herbicide A, B, and C at a particular ratio in contrast to individual herbicides on control of sedges weeds in sugarcane fields.

DETAILED DESCRIPTION OF THE INVENTION
[00037] The following is a detailed description of embodiments of the disclosure. The embodiments are in such detail as to clearly communicate the disclosure. However, the amount of detail offered is not intended to limit the anticipated variations of embodiments; on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present disclosure.
[00038] Each of the appended claims defines a separate invention, which for infringement purposes is recognized as including equivalents to the various elements or limitations specified in the claims. Depending on the context, all references below to the “invention” may in some cases refer to certain specific embodiments only. In other cases it will be recognized that references to the “invention” will refer to subject matter recited in one or more, but not necessarily all, of the claims.
[00039] 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.
[00040] 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 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.
[00041] Various terms as used herein are shown below. To the extent a term used in a claim is not defined below, it should be given the broadest definition persons in the pertinent art have given that term as reflected in printed publications and issued patents at the time of filing.
[00042] Sugarcane is a widely grown perennial grass crop. The main objective of sugarcane crop cultivation is to produce sugar. However, there are many by-products which can be made out of the sugarcane viz. jaggery, bagasse, molasses, press mud, cattle feed which are used by various industries like bagasse based industries, molasses based industries, and press mud based industries.
[00043] Weeds are considered as a major constraint for higher production of sugarcane. Due to weed infestation, the yield loss in sugarcane crop was reported to be as high as 40 to 60%. Weeds can reduce sugarcane yields by competing for moisture, nutrients, and light during the growing season. Several weed species also serve as alternate hosts for disease and insect pests. Heavy weed infestations can also interfere with sugarcane harvest by adding unnecessary harvesting expenses. A weed that is allowed to mature and produce seed will multiply weed control problems by being a source of seed bank replenishment and re-infestation in subsequent years. Therefor ssuccessful weed control is essential for economical sugarcane production.
[00044] Weed control spectrum of widely used herbicides like atrazine, ametryn, 2,4-D, metolachlor, S-metolachlor, asulam, metribuzin, pendimethalin, diuron, hexazinone, trifloxysulfuron-sodium, halosulfuron-methyl, ethoxysulfuron, carfentrazone-ethyl, mesotrione is quite narrow and their weed control efficiency is limited with specific time window of application. Continuous use of herbicides with similar mode of action may lead to the shifting of weed flora and also development of herbicide tolerance. Over dose of the herbicide will also result in phytotoxicity in the crop. In the view of the above facts, it is necessary to develop a suitable combination herbicide which provides not only broad spectrum weeds control but long duration control of weeds with reduced dose of herbicidal active substance.
[00045] There is a constant need in the art for the herbicidal compositions that are synergistic in activity for realizing enhanced benefits over individual herbicide application. Herbicide combinations offer advantages of improved weed control, a wider spectrum of weed coverage, reduced cost, and reduced residue problems.
[00046] The present invention describes the unexpected and surprising effect of a herbicidal composition comprising a) ethyl 2-[(4-chloro-6-methoxypyrimidin-2-yl)carbamoyl sulfamoyl] benzoate (Herbicide-A); b) 4-amino-6-tert-butyl-4,5-dihydro-3-methylthio-1,2,4-triazin-5-one (Herbicide-B), and c) at least one derivative of 2,4-dichlorophenoxyacetic acid (Herbicide-C), which at particular weight ratios shows synergism not only in efficacy in weed control, but also broad applicability to various weeds, and more effective over a longer duration of time.
[00047] In one embodiment of the present invention, the at least one derivative of 2,4-dichlorophenoxy acetic acid is a salt of herbicide C, wherein said salt is selected from the group consisting of sodium, potassium, lithium, ammonium, dimethylamine, diethylamine, triethylamine, isopropylamine, and combinations thereof. Sodium and dimethylamine salts are preferred salts of herbicide C.
[00048] In one embodiment of the present invention, the at least one derivative of 2,4-dichlorophenoxy acetic acid is an ester of herbicide C.
[00049] In an embodiment of the present invention, the ester of herbicide C comprises an alkyl ester selected from the group consisting of methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, 2-ethylhexyl, octyl, isooctyl ester, and combinations thereof. Ethyl and 2-ethylhexyl esters are preferred esters of herbicide C.
[00050] In another embodiment of the present invention, there is provided a method for controlling harmful plants, weeds or unwanted plants comprising applying an effective amount of a composition comprising Herbicide-A, Herbicide-B, and Herbicide-C to harmful plants, weeds or unwanted plants. It is understood and appreciated that the composition and method of weed control of the said invention does not harm plants which are of agronomic use.
[00051] In an embodiment of the present invention, the herbicidal composition can be employed for the selective control of grasses, annual or perennial monocotyledonous or dicotyledonous harmful plants, present in fields of useful plants such as, but not limited to sugarcane, and wheat. Within the intended scope of the invention is also the control of harmful plants found among useful transgenic plants or among useful plants selected by classical means which are resistant to Herbicide-A, Herbicide-B, Herbicide-C, and combination thereof, in particular the synergistic composition of the present invention. Likewise, the composition can be employed for controlling undesirable harmful plants in plantation crops. Among harmful plants, e.g. weeds or volunteer crop plants that may be controlled are includes broad leaf weeds or dicotyledonous weeds for example, Amaranthaceae weeds: Alternanthera tenella, Alternanthera sessilis Amaranthus spp.; Urticaceae weeds: Urtica urens ; Portulacaceae weeds: Portulaca oleracea; Polygonaceae weeds: Polygonum spp, Rumex japonicus, Rumex spinosus, Rumex crispus, Rumex obtusifolius, Rumex acetosa; Caryophyllaceae weeds: Stellaria media, Cerastium holosteoides, Cerastium glomeratum, Spergula arvensis, Silene gallica; Molluginaceae weeds: Mollugo verticillata; Chenopodiaceae weeds: Chenopodium album, Chenopodium mural, Chenopodium ambrosioides, Kochia scoparia, Salsola kali, Atriplex spp; Papaveraceae weeds: Papaver rhoeas, Argemone Mexicana; Brassicaceae weeds: Raphanus raphanistrum, Raphanus sativus, Sinapis arvensis, Capsella bursa-pastoris, Brassica juncea, Brassica campestris, Descurainia pinnata, Rorippa islandica, Rorippa sylvestris, Thlaspi arvense, Myagrum rugosum, Lepidium virginicum, Coronopus didymus ; Capparaceae weeds: Cleome affinis, Cleome viscosa; Fabaceae weeds: Aeschynomene indica, Aeschynomene rudis, Sesbania exaltata, Cassia obtusifolia, Cassia occidentalis, Desmodium tortuosum, Desmodium adscendens, Trifolium repens, Pueraria lobata, Vicia angustifolia, Indigofera hirsuta, Indigofera truxillensis, Vigna sinensis; Oxalidaceae weeds: Oxalis corniculata, Oxalis strica, Oxalis oxyptera; Euphorbiaceae weeds: Euphorbia helioscopia, Euphorbia maculate, Euphorbia humistrata, Euphorbia esula, Euphorbia heterophylla, Euphorbia brasiliensis, Acalypha australis, Croton glandulosus, Croton lobatus, Phyllanthus corcovadensis, Ricinus communis ; Malvaceae weeds: Abutilon theophrasti, Sida rhombiforia, Sida cordifolia, Sida spinosa, Sida glaziovii, Sida santaremnensis, Hibiscus trionum, Anoda cristata, Malvastrum coromandelianum; Cucurbitaceae weeds: Sicyos angulatus, Echinocystis lobata, Momordica charantia; Lythraceae weeds: Lythrum spp.; Primulaceae weeds: Anagallis arvensis; Asclepiadaceae weeds: Asclepias syriaca, Ampelamus albidus; Rubiaceae weeds: Galium aparine, Galium spurium, Richardia brasiliensis, Borreria alata; Convolvulaceae weeds: Ipomoea spp. Convolvulus arvensis, Calystegia spp, Merremia spp.; Solanaceae weeds: Datura stramonium, Solanum nigrum, Solanum americanum, Physalis minima; Scrophulariaceae weeds: Veronica hederaefolia, Veronica persica, Veronica arvensis; Plantaginaceae weeds: Plantago asiatica; Asteraceae weeds: Xanthium pensylvanicum, Xanthium occidentale, Helianthus annuus, Matricaria chamomilla, Matricaria perforata, Chrysanthemum segetum, Matricaria matricarioides, Artemisia princeps, Artemisia vulgaris, Artemisia verlotorum, solidago altissima, Taraxacum officinale, Galinsoga ciliata, Galinsoga parviflora, Senecio vulgaris, Senecio brasiliensis, Senecio grisebachii, Conyza bonariensis, Conyza canadensis, Ambrosia artemisiaefolia, Ambrosia trifida, Bidens pilosa, Bidens frondosa, Bidens subalternans, Cirsium arvense, Cirsium vulgare, Silybum marianum, Carduus nutans, Lactuca serriola, Sonchus oleraceus, Sonchus asper, Wedelia glauca, Melampodium perfoliatum, Emilia sonchifolia, Tagetes minuta, Blainvillea latifolia, Tridax procumbens, Porophyllum ruderale, Acanthospermum australe, Acanthospermum hispidum, Cardiospermum halicacabum, Ageratum conyzoides, Eupatorium perfoliatum, Eclipta alba, Erechtites hieracifolia, Gamochaeta spicata, Gnaphalium spicatum, Jaegeria hirta, Parthenium hysterophorus, Siegesbeckia orientalis, Soliva sessilis; Liliaceae weeds: Allium canadense, Allium vineale; Commelinaceae weeds: Commelina communis, Commelina bengalensis, Commelina erecta; grassy weeds or monocotyledonous weeds for example Poaceae weeds: Echinochloa crus-galli, Setaria viridis, Setaria faberi, Setaria glauca, Setaria geniculata, Digitaria ciliaris, Digitaria sanguinalis, Digitaria horizontalis, Digitaria insularis, Eleusine indica, Poa annua, Alospecurus aequalis, Alopecurus myosuroides, Avena fatua, Sorghum halepense, Sorghum vulgare, Agropyron repens, Lolium multiflorum, Lolium perenne, Lolium rigidum, Bromus secalinus, Bromus tectorum, Hordeum jubatum, Aegilops cylindrica, Phalaris arundinacea, Phalaris minor, Apera spica-venti, Panicum dichotomiflorum, Panicum texanum, Panicum maximum, Brachiaria platyphylla, Brachiaria ruziziensis, Brachiaria plantaginea, Brachiaria decumbens, Brachiaria brizantha, Brachiaria humidicola, Cenchrus echinatus, Cenchrus pauciflorus, Eriochloa villosa, Pennisetum setosum, Chloris gayana, Eragrostis pilosa, Rhynchelitrum repens, Dactyloctenium aegyptium, Ischaemum rugosum, Oryza sativa, Paspalum notatum, Paspalum maritimum, Pennisetum clandestinum, Pennisetum setosum, Rottboellia cochinchinensis and sedges weeds for example Cyperaceae weeds: Cyperus microiria, Cyperus iria, Cyperus odoratus, Cyperus rotundus, Cyperus esculentus or Kyllinga gracillima.
[00052] In another embodiment of the present invention, the composition comprising Herbicide-A, Herbicide-B, and Herbicide-C shows good crop compatibility (i.e. their use in crops does not result in increased damage to crops when compared to the individual application of the herbicidal compounds A, B and C) even though showing synergistic effect against weeds or undesirable plants.
[00053] As described in the ‘Herbicide Handbook of the Weed Science Society of America’, Ninth Edition, 2007, p. 429, “‘synergism’ [is] an interaction of two or more factors such that the effect when combined is greater than the predicted effect based on the response to each factor applied separately.” Synergistic in the herbicide context can mean that the use of Herbicide A, B, and C as described herein results in an enhanced, greater than additive weed control effect compared to the weed control effect of herbicide A, herbicide B or herbicide C individually.
[00054] The terms "herbicide" and "herbicidal" are used herein to denote the inhibitive control or modification of undesired plant growth. Inhibitive control and modification include all deviations from natural development, such as total killing, growth retardation, defoliation, desiccation, regulation, stunting, tillering, stimulation, leaf burn and dwarfing.
[00055] In another embodiment, the present invention relates to the application of said composition comprising Herbicide-A, Herbicide-B, and Herbicide-C, which shows a remarkable improvement in residual activity, which is unexpected from the effects of the individual application of each of herbicide A, herbicide B, and herbicide C. Further, the herbicidal composition of the present invention is very useful in a practical application, since it is capable of controlling, for example, hard to kill weeds in sugarcane fields, such as Commelina spp,. Ipomoea spp, Solanum nigrum, Xanthium spp., among broad leaf weeds, Cyprus rotundus among sedges and Eleusine indica, Panicum spp., Dactyloctenium aegyptium, Brachiaria spp among grassy weeds.
[00056] In another embodiment of the present invention, the herbicidal composition of Herbicide-A, Herbicide-B, and Herbicide-C can be applied in a conventional manner by using techniques familiar to a person skilled in the art. Suitable techniques include, but are not limited to spraying, atomizing, dusting, spreading or watering. The type of application depends on the intended purpose; in any case, it should be ensured that the finest possible distribution or exposing to harmful plant or unwanted plant or locus to be treated by active ingredients according to the invention. The herbicidal composition is applied to unwanted plant or weed locus primarily by spraying, in particular foliar spraying of an aqueous solution of the said composition. Application can be carried out by customary spraying techniques using, for example, water as a carrier and spray liquor rates ranging from about 10 to 2000 l/ha, preferably 50 to 1000 l/ha, and more preferably 100 to 500 l/ha.
[00057] In yet another embodiment of the present invention, the required application rate of the composition comprising Herbicide-A, Herbicide-B, and Herbicide-C depends on various factors such as density of the undesired vegetation, type of soil, development stage of the plants, climatic conditions of the location, and on the application method. In general, the application rate of the composition (total amount of Herbicides A, B and C ranges from 200 to 5000 g/ha, preferably from 300 to 4000 g/ha of Herbicide A, herbicide B, and herbicide C.
[00058] In yet in another embodiment of the present invention, application of the herbicidal composition comprising Herbicide-A, Herbicide-B and Herbicide-C results a remarkable synergistic improvement in the application window (pre-emergence of weeds to post-emergence in weeds under different agronomical cultivation practices of sugarcane) compared to application of herbicide A, B or C individually.
[00059] In another embodiment of the present invention, the herbicidal composition comprising Herbicide-A, Herbicide-B, and Herbicide-C is suitable for combating / controlling common harmful plants in fields, where useful plants shall be planted (i.e. in crops). The composition of the present invention is generally suitable for burndown of undesired harmful plants in fields of the cultivated crops which includes, but not limited to, sugarcane, wheat, potato, sorghum, maize, plantation crops (tea, rubber, coconut, coffee), citrus plantation, mango, grape, non-cropped areas, preferably sugarcane, wheat, plantation crops (tea, rubber, coconut, coffee), citrus plantation, and more preferably sugarcane.
[00060] Compositions containing Herbicide-A, Herbicide-B, and Herbicide-C can be formulated in the form of a single package formulation containing a homogeneous mixture of a Herbicide A, B, and C in any conventional formulation, for example, wettable powders, water dispersible granules (WDG), soluble powders, granules, soluble granules, preferably water dispersible granules (WDG) together with solid carrier materials. If desired, one or more surfactants can be incorporated. Further if desired, one or more auxiliaries customary for crop protection compositions may be added. Such compositions can be formulated using adjuvants wetting agents, adhesives, dispersants or surfactants and, if appropriate, solvent and other agriculturally acceptable additives may be added. Formulation techniques that are known in the art can be adapted to formulating the herbicidal composition further comprising various additives as discussed.
[00061] In a preferred embodiment of the present invention, in said composition, Herbicide A comprises from 0.2% to 2% by weight of the composition.
[00062] In a most preferred embodiment of the present invention, in said composition, Herbicide A comprises 0.8% by weight of the composition.
[00063] In a preferred embodiment of the present invention, Herbicide B comprises from 10% to 60% by weight of the composition.
[00064] In and most preferred embodiment of the present invention, Herbicide B comprises 32% by weight of the composition.
[00065] In a preferred embodiment of the present invention, Herbicide C comprises from 20% to 60% by weight of the composition.
[00066] In a most preferred embodiment of the present invention, Herbicide C comprises 48% by weight of the composition.
[00067] In an embodiment of the present invention, the composition is preferably in the form of a formulation, more preferably in the form of a granular formulation. The granular formulation is preferably in the form of water-dispersible granules or water-soluble granules. An illustrative formulation composition comprising various ingredients is illustrated in the table below:
Ingredient Wt % Range Preferred wt %
Herbicide-A (active ingredient 100% basis ) 0.2 to 2.0% 0.8%
Herbicide-B (active ingredient 100% basis ) 10.0 to 60.0% 32.0%
Herbicide-C (active ingredient 100% basis ) 20.0 to 60% 48.0%
Dispersing Agent
(Blend of Potassium polycarboxylate & Ammonium distyrylphenyl ether sulphate) 1.0 to 12% 3.75%
Wetting Agent (Sodium lauryl sulphate) 1.0 to 12% 4.0%
Surfactant (Napthalene Formaldehyde Condensates) 1.0 to 12% 3.5%
Antifoaming agent (Polydimethylsiloxane)
0.1% to 5% 1.0%
Inert or Fillers 0.0% to 25% 6.95%
Total -- 100%

[00068] In an illustrative embodiment of the present invention, the herbicidal composition further comprises at least one dispersing agent elected from the group consisting of, but not limited to phosphate esters of fatty alcohols, ethoxylated fatty alcohols, ethoxylated tri, di or monostyryl phenol, etho-propoxylated alkoxylated alkyl phenols, phosphate esters of tri, di or monostyryl phenol, alkoxylated tri, di or monostyryl phenol, sulphates of tri, di or monostyryl phenol, alkoxylated tri, di or monostyryl phenol, polycarboxylates, sulphonate of cresol formaldehyde condensates, alkyl naphalene fomaldehyde condensate sulphonates, polyacrylates, ethoxylated alkyl aryl phosphate esters, taurates, styrene acrylic co-polymer, EO-PO block copolymers as such, any fatty alcohols, alcohols or compounds containing at least one OH group, calcium salts of alkyl benzene sulphonate, and combinations thereof.
[00069] In an illustrative embodiment of the present invention, the herbicidal composition further comprises at least one wetting agent selected from the group consisting of, but not limited to salt of lauryl sulphate (e.g. sodium lauryl sulphate, potassium lauryl sulphate etc.), sodium alkylbenzene sulphonate, alkoxylated fatty alcohols, sorbitan esters and its ethoxylates, alkoxylated alkyl phenols, alkoxylated alkyl phenols their sulphate and neutralized salts, sulphated alkyl esters of dibasic acids and its salts, alkyl benzene sulphonates, sulphonates of hydrocarbons (naphthalene), alkyl naphalene sulphonates, silicon alkoxylates, sulphates of fatty alcohols and alkoxylated fatty alcohols and their different alkali earth metal salts, methyl esters of fatty acids and its sulphonates, alpha olefin sulphanates, sulphates of vegetable oil and its ethoxylate, blends of any of the above adsorbed on precipitated silica, and combinations thereof
[00070] In an illustrative embodiment of the present invention, the herbicidal composition further comprises at least one surfactant selected from the group of categories consisting of, but not limited to anionic, cationic, nonionic, amphoteric surfactants, and combinations thereof.
Suitable surfactants are alkali metal, alkaline earth metal, ammonium salts of aromatic sulfonic acids, such as ligninsulfonic acid, phenolsulfonic acid, naphthalenesulfonic acid, dibutylnaphthalene-sulfonic acid and fatty acids, alkylsulfonates, alkyl-arylsulfonates, alkyl sulfates, laurylether sulfates, fatty alcohol sulfates, and sulfated hexa-, hepta- and octadecanolates, sulfated fatty alcohol glycol ethers, condensates of naphthalene or naphthalenesulfonic acid with phenol and formaldehyde, polyoxy-ethylene octylphenyl ether, ethoxylated isooctylphenol, octylphenol, nonylphenol, alkylphenyl polyglycol ethers, tributylphenyl polyglycol ether, tristearyl-phenyl polyglycol ether, alkylaryl polyether alcohols, alcohol and fatty alcohol/ethylene oxide condensates, ethoxylated castor oil, polyoxyethylene alkyl ethers, ethoxylated polyoxypropylene, lauryl alcohol polyglycol ether acetal, sorbitol esters, lignin-sulfite waste liquid and proteins, denatured proteins, polysaccharides (e.g. methylcellulose), hydrophobically modified starches, polyvinyl alcohols, polycarboxylates types, polyalkoxylates, polyvinylamines, polyvinylpyrrolidone and the copolymers thereof.
[00071] In an illustrative embodiment of the present invention, the herbicidal composition further comprises optionally at least one binder, selected from the group consisting of, but not limited to polyvinylpyrolidine, lactose, sucrose, polyethylene glycol, modified starch, modified polyvinyl alcohol, modified carboxymethyl cellulose, emulsions of polyvinyl acetate and polyacrylates and as well as a variety of other materials known to the art and combinations thereof.
[00072] In an illustrative embodiment of the present invention, the herbicidal composition further comprises at least one antifoaming agent selected from the group consisting of, but not limited to silicone emulsions (such as e.g. polydimethylsiloxane, Silikon® SRE, Wacker, Germany or Rhodorsil®, Rhodia, France), long chain alcohols, fatty acids, salts of fatty acids, fluoroorganic compounds, silicone oil, magnesium stearate, and combinations thereof.
[00073] In an illustrative embodiment of the present invention, the herbicidal composition optionally further comprises at least one filler selected from the group consisting of, but not limited to sucrose, lactose, urea, thiourea, salts of alkali earth metals with any strong or weak acid (e.g. sodium chloride, potassium, magnesium chloride etc), citric acid and its salts, ammonium sulphate, ammonium chloride, urea, potash, glycols salts of dibasic acid, carbonate salt (e.g. sodium carbonate, sodium bicarbonate, potassium carbonate, potassium bicarbonate, ammonium carbonate etc.), hydroxide salt (e.g. sodium hydroxide, manganese hydroxide, barium hydroxide octahydrate, aluminum hydroxide, calcium hydroxide, iron hydroxide, barium hydroxide, magnesium hydroxide, ammonium hydroxide, potassium hydroxide, chromium hydroxide, tin hydroxide, chromium hydroxide, silver hydroxide, lead hydroxide, platinum hydroxide, zinc hydroxide, copper hydroxide, beryllium hydroxide, vanadium hydroxide, iron hydroxide, manganese hydroxide, lead hydroxide, strontium hydroxide, tin hydroxide, vanadium hydroxide, lithium hydroxide, mercury hydroxide, nickel hydroxide, mercury hydroxide, copper hydroxide etc.), and combinations thereof. The filler may be inert.
[00074] In an embodiment of the present invention, there is provided a formulation comprising the composition as described herein. The formulation is preferably in granular form.
[00075] In the field of agriculture, it is often understood that the term “synergy” is as defined by Colby S. R. in an article entitled “Calculation of the synergistic and antagonistic responses of herbicide combinations” published in Weeds, 1967, 15, p. 20-22. The action expected for a given combination of two active components can be calculated as follows:
E = X + Y - XY
100
Where,
E= Expected % control by mixture of two products X and Y in a defined dose.
X= Observed % control by product A
Y= Observed % control by product B
[00076] The action expected for a given combination of three active components can be calculated as follows:
E = X + Y + Z - XY+XZ+YZ + XYZ
100 10000

[00077] Where, E represents the expected percentage control of weeds for the combination of the three herbicides at defined doses (for example equal to X, Y, and Z respectively), X is the percentage of weed control observed by herbicide A at a defined dose, Y is the percentage of weed control observed by herbicide B at a defined dose, and Z is the percentage of weed control observed by herbicide C at a defined dose.
[00078] When the percentage of herbicidal control observed (E) for the combination is greater than the expected percentage, synergistic effect of the combination can be inferred. When the percentage of control observed for the combination is equal to the expected percentage, merely an additive effect may be inferred, and wherein the percentage of herbicidal control observed for the combination is lower than the expected percentage, an antagonistic effect of the combinations can be inferred.

EXAMPLES
[00079] The invention will now be illustrated with working examples, which is intended to illustrate the working of disclosure and not intended to take restrictively to imply any limitations on the scope of the present disclosure. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood to one of ordinary skill in the art to which this disclosure belongs.

Example 1
Field experiment methodology
[00080] Three field trials were conducted in commercial cultivated sugarcane field under naturally occurring weed populations in the trial field. The trial sites were located at:
a) Navsari in Gujarat,
b) Villupurum in Tamil Nadu, and
c) Lucknow in Uttar Pradesh (UP).
[00081] The sugarcane crops were grown using normal cultural practices using fertilizer, planting, and maintenance to ensure good growth of the crop and the weeds. To evaluate the bio-efficacy of the herbicides, the treatments applied were as following: Herbicide-A, Herbicide-B, Herbicide-C, and herbicidal composition of the present invention (A+B+C). Commercially available formulation of Herbicide-A (Cyno 25% WP- manufactured by Atul Limited), Herbicide-B (Plasto 70% WP- marketed by Atul Limited), and Herbicide-C (Salix 80% WP- manufactured by Atul Limited) were used as per predetermined doses.
[00082] The trials were conducted using normal research methodology under sufficient weed pressure of the target weeds in the trial fields. In one set of the treatments, the target weed plants in treatment plots were treated with post-emergence foliar spray when weeds were at 3 to 5 leaf stage or 3 to 8 cm height under active growing stage using a backpack hand operated knapsack sprayer fitted with a flat fen nozzle. In another set, the treatment plots were treated as pre-emergence spray after planting of the sugarcane crop but before germination of the weeds. All treatments were applied using a randomized complete block trial design, with 4 replications per treatment, and each plot was about 8 meter long and 4 meter wide. The spray volume was 500L/ha.
[00083] The major weed plants assessed in the field trials were, but not limited to Ipomoea glory, Solanum nigrum, Physalis minima, Cyperus rotundus, Dactyloctenium aegyptium, and Brachiaria reptans.
[00084] The treated plots and the control plots were rated blind at 45 days after herbicide application (DAA) in case of pre-emergence application, and 25 days after application (DAA) in case of post emergence application. Ratings were based on a scale of 0-100%, as discussed above, wherein 0% indicates no damage to the undesired vegetation and 100% indicates complete destruction of the undesired vegetation. All types of plant injury were taken into consideration. The results of such testing as the mean of four replications are summarized in below examples.

Example 2
Bioefficacy Studies
[00085] The invention will now be explained in more detail that illustrates the invention in a non-limiting matter.
[00086] In the following examples, sodium salt of 2,4-dichlorophenoxyacetic acid (Herbicude C) was taken for making granular formulation for various bioefficacy or phytotoxicity studies.
[00087] Composition of the granular formulation
Ingredients Weight %
Herbicide-A 0.8%
Herbicide-B 32%
Herbicide-C 48%
Dispersing Agent
(Blend of Potassium polycarboxylate & Ammonium distyryl phenyl ether sulphate) 3.75%
Wetting Agent (Sodium lauryl sulphate) 4.0%
Surfactant (Napthalene Formaldehyde Condensates) 3.5%
Antifoaming agent (Polydimethylsiloxane) 1.0%
Inert/Fillers 6.95%
Total 100%

[00088] The various experiments were carried out to determine the synergistic herbicidal effects of the composition comprising a mixture of Herbicide (A+B+C) as defined above.
[00089] Below examples (2.1a, 2.1b, 2.2a, 2.2b, 2.3a, 2.3b, 2.4a, 2.4b, 2.5a, 2.5b, and 2.6a) summarizes the impact of individual or combined herbicide treatments at 3 different doses against key weeds in sugarcane crop as post emergence spray (3 to 5 leaf stage of weeds) or pre-emergence spray i.e. after planting of sugarcane and before germination of harmful weeds plants.

Example 2.1a:
[00090] Control of Solanum nigrum (Broad leaf weed) by post emergence spray (Lucknow –UP)

Active ingredient g.a.i./ha % of control observed
(25 DAA) % of control expected Colby ratio
o/e
Herbicide-A 24 42.3 - -
Herbicide-B 960 23.8 - -
Herbicide-C 1440 78.7 - -
Herbicide (A+B+C) 24+960+1440 96.5 90.6 1.06
Herbicide-A 20 26.0 - -
Herbicide-B 800 19.9 - -
Herbicide-C 1200 66.1 - -
Herbicide (A+B+C) 20+800+1200 94.7 79.9 1.19
Herbicide-A 16 21.8 - -
Herbicide-B 640 17.1 - -
Herbicide-C 960 59.6 - -
Herbicide (A+B+C) 16+640+960 81.9 73.8 1.11
(Here DAA= Days after application)

Example 2.1b:
[00091] Control of Solanum nigrum (Broad leaf weed) by pre- emergence spray (Lucknow –UP)
Active ingredient g.a.i./ha % of control observed
(45 DAA) % of control expected Colby ratio
o/e
Herbicide-A 24 67.4 - -
Herbicide-B 960 55.3 - -
Herbicide-C 1440 0.0 - -
Herbicide (A+B+C) 24+960+1440 98.8 85.4 1.15
Herbicide-A 20 59.3 - -
Herbicide-B 800 41.6 - -
Herbicide-C 1200 0.0 - -
Herbicide (A+B+C) 20+800+1200 96.8 76.2 1.27
Herbicide-A 16 48.7 - -
Herbicide-B 640 37.0 - -
Herbicide-C 960 0.0 - -
Herbicide (A+B+C) 16+640+960 84.3 67.7 1.24

Example 2.2a:
[00092] Control of Ipomoea glory (Broad leaf weed) by post emergence spray (Navsari-Gujarat)
Active ingredient g.a.i./ha % of control observed
(25 DAA) % of control expected Colby ratio
o/e
Herbicide-A 24 27.5 - -
Herbicide-B 960 44.7 - -
Herbicide-C 1440 62.8 - -
Herbicide (A+B+C) 24+960+1440 87.3 85.1 1.03
Herbicide-A 20 14.9 - -
Herbicide-B 800 44.1 - -
Herbicide-C 1200 55.4 - -
Herbicide (A+B+C) 20+800+1200 84.1 78.8 1.07
Herbicide-A 16 12.2 - -
Herbicide-B 640 38.3 - -
Herbicide-C 960 51.7 - -
Herbicide (A+B+C) 16+640+960 79.0 73.8 1.07

Example 2.2b:
[00093] Control of Ipomoea glory (Broad leaf weed) by pre- emergence spray (Navsari-Gujarat)
Active ingredient g.a.i./ha % of control observed
(45 DAA) % of control expected Colby ratio
o/e
Herbicide-A 24 72.1 - -
Herbicide-B 960 61.9 - -
Herbicide-C 1440 0.0 - -
Herbicide (A+B+C) 24+960+1440 99.3 89.4 1.11
Herbicide-A 20 68.8 - -
Herbicide-B 800 55.2 - -
Herbicide-C 1200 0.0 - -
Herbicide (A+B+C) 20+800+1200 97.6 86.0 1.13
Herbicide-A 16 59.5 - -
Herbicide-B 640 48.1 - -
Herbicide-C 960 0.0 - -
Herbicide (A+B+C) 16+640+960 87.2 79.0 1.10

Example 2.3a:
[00094] Control of Physalis minima (Broad leaf weed) by post emergence spray (Navsari-Gujarat)
Active ingredient g.a.i./ha % of control observed
(25 DAA) % of control expected Colby ratio
o/e
Herbicide-A 24 65.3 - -
Herbicide-B 960 52.0 - -
Herbicide-C 1440 50.5 - -
Herbicide (A+B+C) 24+960+1440 97.7 91.8 1.06
Herbicide-A 20 60.3 - -
Herbicide-B 800 48.7 - -
Herbicide-C 1200 40.0 - -
Herbicide (A+B+C) 20+800+1200 96.7 87.8 1.10
Herbicide-A 16 52.5 - -
Herbicide-B 640 45.0 - -
Herbicide-C 960 42.7 - -
Herbicide (A+B+C) 16+640+960 91.7 85.0 1.08

Example 2.3b:
[00095] Control of Physalis minima (Broad leaf weed) by pre- emergence spray (Navsari-Gujarat)
Active ingredient g.a.i./ha % of control observed
(45 DAA) % of control expected Colby ratio
o/e
Herbicide-A 24 77.3 - -
Herbicide-B 960 80.0 - -
Herbicide-C 1440 0.0 - -
Herbicide (A+B+C) 24+960+1440 100.0 95.5 1.05
Herbicide-A 20 73.5 - -
Herbicide-B 800 75.3 - -
Herbicide-C 1200 0.0 - -
Herbicide (A+B+C) 20+800+1200 100.0 93.5 1.07
Herbicide-A 16 65.5 - -
Herbicide-B 640 71.3 - -
Herbicide-C 960 0.0 - -
Herbicide (A+B+C) 16+640+960 96.5 90.1 1.07

Example 2.4a:
[00096] Control of Dactyloctenium aegyptium (grassy weed) by post emergence spray (Lucknow –UP)
Active ingredient g.a.i./ha % of control observed
(25 DAA) % of control expected Colby ratio
o/e
Herbicide-A 24 15.5 - -
Herbicide-B 960 75.0 - -
Herbicide-C 1440 0.0 - -
Herbicide (A+B+C) 24+960+1440 85.5 78.9 1.08
Herbicide-A 20 10.0 - -
Herbicide-B 800 72.3 - -
Herbicide-C 1200 0.0 - -
Herbicide (A+B+C) 20+800+1200 81.0 75.1 1.08
Herbicide-A 16 7.0 - -
Herbicide-B 640 65.7 - -
Herbicide-C 960 0.0 - -
Herbicide (A+B+C) 16+640+960 72.3 68.1 1.06

Example 2.4b:
[00097] Control of Dactyloctenium aegyptium (grassy weed) by pre- emergence spray (Lucknow –UP)
Active ingredient g.a.i./ha % of control observed
(45 DAA) % of control expected Colby ratio
o/e
Herbicide-A 24 27.0 - -
Herbicide-B 960 81.3 - -
Herbicide-C 1440 0.0 - -
Herbicide (A+B+C) 24+960+1440 96.0 86.3 1.11
Herbicide-A 20 18.5 - -
Herbicide-B 800 72.3 - -
Herbicide-C 1200 0.0 - -
Herbicide (A+B+C) 20+800+1200 93.5 77.4 1.22
Herbicide-A 16 15.3 - -
Herbicide-B 640 68.7 - -
Herbicide-C 960 0.0 - -
Herbicide (A+B+C) 16+640+960 85.0 73.5 1.16

Example 2.5a:
[00098] Control of Brachiaria reptans (grassy weed) by post emergence spray (Navsari-Gujarat)
Active ingredient g.a.i./ha % of control observed
(25 DAA) % of control expected Colby ratio
o/e
Herbicide-A 24 0.0 - -
Herbicide-B 960 81.3 - -
Herbicide-C 1440 0.0 - -
Herbicide (A+B+C) 24+960+1440 83.0 81.3 1.02
Herbicide-A 20 0.0 - -
Herbicide-B 800 80.0 - -
Herbicide-C 1200 0.0 - -
Herbicide (A+B+C) 20+800+1200 81.0 80.0 1.01
Herbicide-A 16 0.0 - -
Herbicide-B 640 70.5 - -
Herbicide-C 960 0.0 - -
Herbicide (A+B+C) 16+640+960 71.0 70.5 1.01

Example 2.5b:
[00099] Control of Brachiaria reptans (grassy weed) by pre- emergence spray (Navsari-Gujarat)
Active ingredient g.a.i./ha % of control observed
(45 DAA) % of control expected Colby ratio
o/e
Herbicide-A 24 22.3 - -
Herbicide-B 960 86.3 - -
Herbicide-C 1440 0.0 - -
Herbicide (A+B+C) 24+960+1440 98.3 89.4 1.10
Herbicide-A 20 15.7 - -
Herbicide-B 800 83.3 - -
Herbicide-C 1200 0.0 - -
Herbicide (A+B+C) 20+800+1200 95.5 85.9 1.11
Herbicide-A 16 12.5 - -
Herbicide-B 640 76.5 - -
Herbicide-C 960 0.0 - -
Herbicide (A+B+C) 16+640+960 87.3 79.4 1.10

Example 2.6a:
[000100] Control of Cyprus rotundus (sedges weed) by post emergence spray (Villupuram- Tamilnadu)
Active ingredient g.a.i./ha % of control observed
(25 DAA) % of control expected Colby ratio
o/e
Herbicide-A 24 68.3 - -
Herbicide-B 960 0.0 - -
Herbicide-C 1440 52.5 - -
Herbicide (A+B+C) 24+960+1440 93.7 84.9 1.10
Herbicide-A 20 61.0 - -
Herbicide-B 800 0.0 - -
Herbicide-C 1200 48.5 - -
Herbicide (A+B+C) 20+800+1200 91.5 79.8 1.15
Herbicide-A 16 52.5 - -
Herbicide-B 640 0.0 - -
Herbicide-C 960 44.5 - -
Herbicide (A+B+C) 16+640+960 79.5 73.6 1.08

[000101] It can be appreciated from the observed results presented hereinabove that in each case, for any of the 3 doses of the combination of herbicide A, B, and C tested (at fixed w/w ratio of 1:20:60), the effect of the composition either in pre- or post-emergence application is unexpectedly and surprisingly synergistic over the effect of individual herbicides A, B or C. The synergistic effect can be seen for Solanum nigrum (Broad leaf weed) , Ipomoea glory (Broad leaf weed), Physalis minima (Broad leaf weed) , Dactyloctenium aegyptium (grassy weed), Brachiaria reptans (grassy weed) and Cyprus rotundus (sedges weed) respectively.
[000102] Figure 1 depicts the graphical representation of the effect of herbicide A, B, C or A+B+C at particular doses applied post emergence on grassy weed control (Echinochloa spp, Brachiaria spp., and Dactyloctenium spp) measured 15-45 days post application. It can be appreciated from Figure 1 that herbicide C alone at 960 g.a.i./ha has no inhibitory effect on weed growth. Herbicide A alone at 24 g.a.i./ha has a less than 10% inhibitory effect on weed growth as measured on day 15 post application, however, at later stages, no inhibitory effect can be observed. Herbicide B at 640 g.a.i/ha inhibits weed growth by about 80% by day 15, however the effect is reduced to about 50% by day 45. In contrast, the combination of Herbicide A, B, and C at 24, 640, and 960 g/ha shows 90% weed control from day 15 through day 30, which drops only marginally to about 80% by day 45, thus showing the enhanced long term effect of the particular herbicidal composition of the present invention.
[000103] Figure 2 depicts the graphical representation of the effect of herbicide A, B, C or A+B+C at particular doses applied post emergence on broad leaf weed control (Ipomoea spp, Solanum spp, and Physalis spp) measured 15-45 days post application. It can be appreciated from Figure 2 that herbicide C alone at 960 g.a.i./ha inhibits broad leaf weeds by about 70% by day 15, which drops to about 25% by day 30, and no effect can be seen by day 45. Herbicide B at 640 g.a.i/ha inhibits broad leaf weeds by about 55% by day 15, which drops marginally by 10% by day 30, and by day 45, the effect is reduced to about 20%. Herbicide A alone at 24 g.a.i./ha inhibits broad leaf weeds by about 35% by day 15 and 30, but only about 20% by day 45. In contrast, the combination of Herbicide A, B, and C at 24, 640, and 960 g/ha shows about 95%weed control by day 15, which only drops marginally to 90% by day 30 and by day 45 the combination still shows about 75% inhibition, thus showing the enhanced long term effect of the particular herbicidal composition of the present invention.
[000104] Figure 3 depicts the graphical representation of the effect of herbicide A, B, C or A+B+C at particular doses applied post emergence on sedges weed control (Cyperus spp) measured 15-45 days post application. It can be appreciated from Figure 3 that herbicide C alone at 960 g.a.i./ha has no discernible inhibitory effect on weed control even as early as 15 days post application. Herbicide B at 640 g.a.i/ha at 15 days post application only shows about a 30% inhibition of weed growth, which reduces to 22% and 15% by day 30 and 45 respectively. Herbicide A alone at 24 g.a.i./ha shows about a 58% inhibition by day 15, which drops to about 41% and 33% by day 30 and 4 respectively. In contrast, the combination of Herbicide A, B, and C at 24, 640, and 960 g/ha shows about a 91% sedges weed control by day 15, which marginally drops to about 88% by day 30, and to 62% by day 45, thus showing the enhanced long term effect of the particular herbicidal composition of the present invention.
[000105] Overall, it can be appreciated from Figures 1-3 that the combination of herbicide A, B, and C at particular doses exhibits enhanced effect on control of a wide variety of weeds over a longer duration of time compared to the effect of herbicide A, B or C alone.
[000106] Accordingly, by the practice of the present invention, herbicide compositions having heretofore unrecognized characteristics are prepared. These herbicides exhibit exceptionally synergetic effect for control of common weeds, especially in the growing of sugarcane field and are used in either a pre-emergence or post-emergence herbicide application.

Example 3
Phytotoxicity Studies
[000107] To assess the phytotoxic effect of the herbicidal composition of the present invention comprising Herbicide (A,B, and C on sugarcane crop viz. yellowing, stunting, scorching, epinasty, hyponasty etc., a trial was laid out in Randomized Black Design (RBD) replicated four times. For each treatment, plot size of was maintained at 10m length and 4 m width. To raise the crops, all the agronomical practices were followed as usually adopted for sugarcane cultivation. The said herbicidal composition comprising Herbicide (A+B+C) or individual herbicides A, B, and C were applied in prescribed doses using commercially available product in market by hand pumped backpack sprayer fitted with flat fen nozzle and a spray volume of 500 liters per hectare (L/ha). Untreated control plots were also sprayed with 500 l /ha water alone. The various herbicidal treatments were made as post emergence application at 20 days after sugarcane germination.
[000108] Observation on phytotoxicity viz growth stunting, yellowing, scorching, epinasty, hyponasty etc. was recorded at 10 and 20 days after application of treatments from ten plants which were randomly selected from each plot.
[000109] Phytotoxic impacts of separate and combined treatments at different concentration of Herbicide A, B and C on sugarcane crop as post emergence spray (Villupuram-Tamil Nadu)
Active ingredient g.a.i./ha % phytotoxic effect on sugarcane crop
10 DAA 20 DAA
Herbicide-A 24 0.0 0.0
Herbicide-B 960 5.0 4.0
Herbicide-C 1440 0.0 0.0
Herbicide (A+B+C) 24+960+1440 4.5 4.0
Herbicide-A 20 0.0 0.0
Herbicide-B 800 3.7 3.5
Herbicide-C 1200 0.0 0.0
Herbicide (A+B+C) 20+800+1200 3.0 2.5
Herbicide-A 16 0.0 0.0
Herbicide-B 640 0.0 0.0
Herbicide-C 960 0.0 0.0
Herbicide (A+B+C) 16+640+960 0.0 0.0
(Here DAA= Days after application)
[000110] It can be appreciated from the observed results presented hereinabove that the herbicidal composition of the said invention at the various dose amounts (w/w ratio of 1:20:60 of herbicide A:B:C) as tested exhibits either less or comparable sugarcane crop phytotoxicity as compared to phytotoxicity observed upon treatment with any one of Herbicide A, B or C individually.
[000111] Overall, the present invention provides a composition comprising three herbicidal compounds, which at particular w/w ratios, and in various doses exhibit an unexpected and surprising synergism in ability to eliminate growth of weeds and unwanted vegetation. Of particular importance is that the said composition, while it is detrimental to the growth of weeds, does not particularly affect agronomic characteristics of crop plant such as sugarcane. The said composition is not phytotoxic to the crop plants, which makes the said composition an attractive and suitable alternative to usage of individual herbicides.
[000112] The compositions and methods of the appended claims are not limited in scope by the specific compositions and methods described herein, which are intended as illustrations of a few aspects of the claims and any compositions and methods that are functionally equivalent are intended to fall within the scope of the claims. Various modifications of the compositions and methods in addition to those shown and described herein are intended to fall within the scope of the appended claims. Further, while only certain representative compositions and method steps disclosed herein are specifically described, other combinations of the compositions and method steps also are intended to fall within the scope of the appended claims, even if not specifically recited. Thus, a combination of steps, elements, components, or constituents may be explicitly mentioned herein; however, other combinations of steps, elements, components, and constituents are included, even though not explicitly stated. The term “comprising” and variations thereof as used herein is used synonymously with the term “including” and variations thereof and are open, non-limiting terms. Although the terms “comprising” and “including” have been used herein to describe various embodiments, the terms “consisting essentially of’ and “consisting of’ can be used in place of “comprising” and “including” to provide for more specific embodiments of the invention and are also disclosed. Other than in the examples, or where otherwise noted, all numbers expressing quantities of ingredients, reaction conditions, and so forth used in the specification and claims are to be understood at the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, to be construed in light of the number of significant digits and ordinary rounding approaches.
[000113] The numerical values of various parameters given in the specification are at approximations and slightly higher or slightly lower values of these parameters fall within the ambit and the scope of the invention.
[000114] While considerable emphasis has been placed herein on the specific steps of the preferred process, it will be highly appreciated that many steps can be made and that many changes can be made in the preferred steps without departing from the principles of the invention. These and other changes in the preferred steps of the invention will be apparent to those skilled in the art from the disclosures herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the invention and not as a limitation.