Description:HERBICIDAL COMPOSITION

FIELD OF INVENTION:
The present invention relates to a novel, stable, synergistic herbicidal composition for broad spectrum control of weeds in soybean crops. The invention further relates to a process for preparation thereof.

BACKGROUND OF THE INVENTION:
Herbicides are chemicals used to manipulate or control undesirable vegetation. Herbicide application occurs most frequently in row-crop farming, where they are applied before or during planting to maximize crop productivity by minimizing other vegetation. In suburban and urban areas, herbicides are applied to lawns, parks, golf courses and other areas. Herbicides are also applied to water bodies to control aquatic weeds.

The losses caused by weeds in agricultural production environments include reduced crop quality, increased irrigation costs, increased harvesting costs, reduced land value, injury to livestock and crop damage from insects and pests harbored by weeds. Most importantly, weeds compete with crop plants for nutrients, sunlight and other resources. Thus, weed control is an important step undertaken to ensure good crop growth.

The use of herbicide combination is well accepted practice known to the farmer community. However, using a combination of multiple herbicides poses challenges because it is akin to mixing up a bunch of herbicides with distinct chemical and physical characteristics. Additionally, it presents difficulties for the formulator in terms of stability and compatibility of each individual herbicide as well as the excipients or adjuvants utilized in the formulation. There is thus an ever growing need to develop herbicidal combinations that not only provide satisfactory control of weeds in the agricultural fields but also are non-phytotoxic to the treated crops. There is also a need to develop agrochemical formulations which are physically and chemically stable and provide enhanced efficacy over individual actives.

Diclosulam:
Diclosulam (N-(2,6-dichlorophenyl)-5-ethoxy-7-fluoro-[1,2,4]triazolo[1,5-c]pyrimidine-2-sulfonamide) [CAS identifier 145701-21-9] is a herbicide belonging to Triazolopyrimidine, sulphonamide family. It is primarily used for the control of annual and certain perennial broadleaf weeds when applied as soil, foliar, or burndown treatments in crops such as sugar cane, peanuts and soybeans, as well as forestry applications. It is taken up by both roots and foliage and translocated to new growing points. Lethal amounts of Diclosulam accumulate in meristems, halting cell division and resulting in plant death. Very little Diclosulam accumulates in plant roots. It acts by inhibiting the acetolactate synthase enzyme. The primary site of activity is within chloroplasts in plant meristems. It is applied for weed control in crops like Peanuts; Soybeans; Sorghum; Potatoes; Maize; Cereals including wheat, barley, oats. The structure is depicted below:

Flumioxazin
Flumioxazin [CAS identifier 103361-09-7] (IUPAC name: 2-(7-fluoro-3-oxo-4-prop-2-ynyl-1,4-benzoxazin-6-yl)-4,5,6,7-tetrahydroisoindole-1,3-dione is a broad-spectrum contact herbicide. A protoporphyrinogen oxidase inhibitor, the mode of action in this family of herbicides is believed to be inhibition of protoporphyrinogen oxidase, an enzyme important in the synthesis of chlorophyll. Mechanistic study findings suggest that porphyrins accumulate in susceptible plants causing photosensitization, which leads to membrane lipid peroxidation. The peroxidation of membrane lipids leads to irreversible damage of membrane function and structure in susceptible plants. Treatment of soil with flumioxazin will cause susceptible emerging plants to turn necrotic and die shortly after exposure to sunlight. Flumioxazin is used on soybeans, peanuts, orchard fruits and other crops.

The chemical structure is depicted below:

Imazethapyr (IUPAC : 3-Pyridinecarboxylic acid, 2-[4,5-dihydro-4-methyl-4-(1-methylethyl)-5-oxo-1H-imidazol-2-yl]-5-ethyl- is another known herbicide. Imazethapyr is an imidazole compound used as a selective herbicide. It is applied as preplant, pre-emergence and postemergence herbicide. The compound controls weeds by reducing the levels of three branched-chain aliphatic amino acids, isoleucine, leucine and valine, through the inhibition of aceto-hydroxyacid synthase, an enzyme common to the biosynthetic pathway for these amino acids. This inhibition causes a disruption in protein synthesis which, in turn, leads to an interference in DNA synthesis and cell growth. The compound is used to control grasses and broadleaved weeds including barnyard grass, crabgrass, cocklebur, panicums, pigweeds, nightshade, mustard, smartweed, velvetleaf, jimsonweed, foxtails, seedling Johnson grass, lambs quarters, morning-glory and others. Tolerant crops include soybeans, peanuts, dry and edible beans, peas, alfalfa and imidazolinone resistant/tolerant corn. Additional research is being conducted on other leguminous crops.

The chemical structure is depicted below:

Even though the above mentioned herbicidal active ingredients are individually known, yet there is a need to develop a stable ready to use composition comprising these actives which when combined at specific weight percentages result in broad spectrum control of obnoxious weeds, particularly in soybean crop without any noticeable phytotoxicity.

The present inventors have surprisingly found that when the above-mentioned actives are combined in specified weight percentage, the resulting herbicidal composition provides superior control of weeds without any kind of crop injury, phytotoxicity and no carryover problems and additionally achieves reduction in the dose of the actives applied to the crops, while resulting in enhanced efficacy in terms of percent weed control.

OBJECT OF THE INVENTION
It is an object of the present invention to provide a stable, synergistic, broad spectrum herbicidal composition comprising the active ingredient combination of Diclosulam, Flumioxazin and Imazethapyr for effectively controlling broad leaved weeds and narrow leaved weeds in soybean crop.
It is yet another object of the present invention to provide a stable, synergistic oil dispersion comprising Diclosulam, Flumioxazin and Imazethapyr as active ingredients along with at least one agriculturally acceptable excipient.

It is yet another object of the present invention to provide a herbicidal composition comprising Diclosulam, Flumioxazin, Imazethapyr and vegetable oil along with at least one agriculturally acceptable excipient.

It is yet another object of the present invention to provide a process for preparing an oil dispersion comprising Diclosulam, Flumioxazin and Imazethapyr as active ingredients along with at least one agriculturally acceptable excipient.

It is yet another object of the present invention to provide a method of controlling broad leaved and narrow leaved weeds in agricultural crops particularly soybean wherein said method comprises applying the desired amount of the said herbicidal composition to the target crop or locus.

SUMMARY OF THE INVENTION
In one aspect, the present invention provides a novel, stable, synergistic, environmentally safe, cost-effective herbicidal composition comprising:
a) Diclosulam in an amount ranging from 1-10% w/w;
b) Flumioxazin in an amount ranging from 5-25% w/w;
c) Imazethapyr in an amount ranging from 5-15% w/w;
d) at least one agriculturally acceptable excipient.

In yet another aspect, the present invention provides a novel, stable, synergistic, environmentally safe, cost-effective herbicidal composition comprising:
a) Diclosulam in an amount ranging from 1-10% w/w;
b) Flumioxazin in an amount ranging from 5-25% w/w;
c) Imazethapyr in an amount ranging from 5-15% w/w;
d) Vegetable oil in an amount ranging from 0.05-2% and;
e) at least one agriculturally acceptable excipient.

In another aspect, the present invention provides a process for preparation of an herbicidal composition, comprising the following steps:
Step 1: solubilizing dispersing agent, emulsifier, solvent (and vegetable oil) with a high shear mixer to obtain a homogeneous mixture.
Step 2: adding Imazethapyr technical, Flumioxazin technical to the homogenous mixture, followed by adding Diclosulam technical to obtain a homogenous mass;
Step 3: grinding the homogenous mass in a sand mill to obtain a particle size less than 15µ (microns); and
Step 4: mixing the material obtained in step (c) in a post mixer, followed by adding an anti-caking agent and mixing well to obtain an oil dispersion formulation.

In another aspect, the present invention provides a method for controlling undesirable weeds in soybean crop, said method comprising treating the locus at which the crop is growing or intended to be grown with a herbicidal composition comprising a) a herbicidally effective amount of Diclosulam, b) a herbicidally effective amount of Flumioxazin, c) a herbicidally effective amount of Imazethapyr along with at least one agriculturally acceptable excipient.

In yet another aspect, the present invention provides a method for controlling undesirable weeds in soybean crop, said method comprising treating the locus at which the crop is growing or intended to be grown with a herbicidal composition comprising a) a herbicidally effective amount of Diclosulam, b) a herbicidally effective amount of Flumioxazin, c) a herbicidally effective amount of Imazethapyr d) vegetable oil along with at least one agriculturally acceptable excipient.

TECHNICAL ADVANCEMENT OF THE INVENTION:
The herbicidal composition as disclosed in the present invention comprises Diclosulam, Flumioxazin and Imazethapyr as actives as described herein above and has several associated technical advantages including but not limited to:
?synergistic effect
?broad spectrum control in weed management in agricultural crops specially soybean
?reduced dosage of actives
?plant health benefits; and
?Crop safety (negligible phytotoxicity)
DETAILED DESCRIPTION OF THE INVENTION:
Those skilled in the art will be aware that the invention described herein is subject to variations and modifications other than those specifically described. It is to be understood that the invention described herein includes all such variations and modifications. The invention also includes all such steps, features, compositions, and compounds referred to or indicated in this specification, individually or collectively, and all compositions of any two or more of said steps or features.

The instant invention does not use any biological material originating in India. Vegetable oil, that may be used in the instant invention is not obtained from India and was procured from an imported source.

Abbreviations

D.M.

Demineralized Water
RTU Ready to Use
MEC Micro Emulsion Concentrate
QS Quantum Satis
A.I/ a.i Active Ingredient
DAA Days After Application
a.i/ha Dosage of active ingredient per hectare
BLW Broad leaved weeds
NLW Narrow leaved weeds

Unless otherwise specified, all terms used in disclosing the invention, including technical and scientific terms, have the meaning as commonly understood by one of the ordinary skills in the art to which the invention belongs. For further guidance, term definitions may be included to better appreciate the teaching of the present invention.

As used herein, the term “plant” refers to any plant or part thereof including serial 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 parts of the plants may or may not be attached to the remainder of the plant.

As used herein, the term “weed” refers to the unwanted plant which competes for resources with the crop or plant of interest.
As used herein, the term “herbicide” refers to a substance which adversely affects the existence and growth of the target weed.

As used herein the term “herbicidally effective amount” is that quantity of the herbicide active ingredient, applied in an amount which will provide the required control of weed on commercial crops. The amount is dependent upon many factors including, for example, type of formulations, the crop, weed sought to be controlled and environmental conditions.

As used herein, the term “agriculturally acceptable excipient” refers to an ingredient, additive, component or supplement, liquid or solid, suitable for incorporation in agricultural compositions.

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”.

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.

The details of biological material used in the present invention:
In an embodiment, the herbicidal composition of the present composition comprises vegetable oil as a synergist. Using vegetable oil along with the herbicidal combination offers several advantages. Some of these advantages are listed below:

? Biodegradability: Vegetable oils are generally biodegradable, meaning they break down naturally over time. This reduces the accumulation of harmful chemicals in soil and water bodies, promoting environmental health.
? Low Toxicity: Vegetable oils tend to have low toxicity levels compared to synthetic chemicals commonly used in herbicides. This characteristic reduces the risk of harm to non-target organisms, including humans, animals, and beneficial insects.
? Selective Weed Control: Vegetable oil-based herbicides can offer selective weed control, targeting specific types of weeds while sparing desired crops or vegetation. This selectivity minimizes damage to crops.
? Adhesion and Penetration: Vegetable oils can enhance the adhesion and penetration of herbicidal compounds onto plant surfaces. This improves the efficacy of the herbicide by ensuring better coverage and absorption by target weeds, leading to more effective weed control.
? Synergistic Effects: Vegetable oils may enhance the performance of herbicidal compounds through synergistic effects. They help herbicides penetrate plant tissues more effectively and increasing their overall efficacy.
? Reduced Runoff: Vegetable oil-based herbicides can reduce runoff compared to water-soluble herbicides. This helps prevent the contamination of nearby water sources with herbicidal chemicals, preserving aquatic ecosystems and water quality.

These benefits make vegetable oil-based herbicides a promising option for sustainable weed management in agriculture.

The vegetable oil was procured from 4825 Jalan Permatang Pauh, 13400 Butterworth, P.W. Malaysia. The present invention does not use any biological material originating in India.

The present inventors have surprisingly found that the presently disclosed synergistic herbicidal composition provides enhanced control of weeds in target crops at a substantially reduced active dosage, thus reducing environmental load of chemicals.

In an embodiment, the present invention provides a novel, stable, synergistic herbicidal composition comprising Diclosulam, Flumioxazin, Imazethapyr and at least one agriculturally acceptable excipient.

In an embodiment, the present invention provides a novel, stable, synergistic herbicidal composition comprising Diclosulam, Flumioxazin, Imazethapyr, vegetable oil and at least one agriculturally acceptable excipient.

In an embodiment, the present invention provides a novel, stable, synergistic herbicidal composition comprising Diclosulam in an amount ranging from 1-10% w/w, Flumioxazin in an amount ranging from 5-25% w/w, Imazethapyr in an amount ranging from 5-15% w/w and at least one agriculturally acceptable excipient.

In an embodiment, the present invention provides a novel, stable, synergistic herbicidal composition comprising Diclosulam in an amount ranging from 1-10% w/w, Flumioxazin in an amount ranging from 5-25% w/w, Imazethapyr in an amount ranging from 5-15% w/w, vegetable oil in an amount ranging from 0.05-2% w/w.

In a preferred embodiment, the present invention provides a novel, stable, synergistic herbicidal composition comprising Diclosulam in an amount of 2.8% w/w, Flumioxazin in an amount of 7.5%, Imazethapyr in an amount of 7.5% w/w, and at least one agriculturally acceptable excipient.

In a preferred embodiment, the present invention provides a novel, stable, synergistic herbicidal composition comprising Diclosulam in an amount of 2.8% w/w, Flumioxazin in an amount of 7.5%, Imazethapyr in an amount of 7.5% w/w, vegetable oil in an amount of 0.3% w/w and at least one agriculturally acceptable excipient.

In an embodiment of the present invention, said at least one agriculturally acceptable excipient is selected from the group consisting of at least one dispersing agent, at least one emulsifier, at least one anti-caking agent, at least one solvent and a combination thereof.

In an embodiment of the present invention, said at least one dispersing agent is selected from the group consisting of sodium lignosulphonates, sodium naphthalene sulphonate- formaldehyde condensates, aliphatic alcohol ethoxylates, tristyrylphenol ethoxylates potassium salt and esters, ethylene oxide/propylene oxide block copolymers, vegetable oil ethoxylate and combination thereof.

In a preferred embodiment of the present invention, said at least one dispersing agent is vegetable oil ethoxylate.

In an embodiment of the present invention, said at least one dispersing agent is present in an amount ranging from 11-25% w/w.
In a preferred embodiment of the present invention, said at least one dispersing agent is present in an amount of 15% w/w.

In an embodiment of the present invention, said at least one emulsifier is selected from the group consisting of alkyl aryl EO-PO ethoxylates, Polysorbate 80/ Tween 80, Polysorbate 20/Tween 20, PEG400/PEG 200, Sorbitan hexa oleate/Sorbitan tri-oleate.

In a preferred embodiment of the present invention, said at least one emulsifier is alkyl aryl EO-PO ethoxylates.

In an embodiment of the present invention, at least one emulsifier is present in an amount ranging from 2-15% w/w.

In a preferred embodiment of the present invention, at least one emulsifier is present in an amount of 5% w/w.

In an embodiment of the present invention, said at least one anti-caking agent is selected from the group consisting of Silicon dioxide, Sodium-alumina silicate, Micro-crystalline cellulose, Lignin based anti-caking agent, Tri-calcium phosphate, hydrophobic silica.

In a preferred embodiment of the present invention, said at least one anti-caking agent is hydrophobic silica.

In an embodiment of the present invention, said at least one anti-caking agent is present in an amount ranging from 0.5-5% w/w.

In a preferred embodiment of the present invention, said at least one anti-caking agent is present in an amount of 1.50% w/w.

In an embodiment of the present invention, said at least one solvent is selected from the group consisting of Paraffinic oil, methyl oleate, methyl soyate, vegetable oil or methylated seed oil, oleic acid methyl ester.

In a preferred embodiment of the present invention, said at least one solvent is oleic acid methyl ester.

In an embodiment of the present invention, said at least one solvent is present in amount ranging from 35-60% w/w.

In a preferred embodiment of the present invention, said at least one solvent is present in amount of 51.70% w/w.

In an embodiment of the present invention, said herbicidal composition is formulated in a form selected from the group comprising water-soluble concentrates (SL), emulsifiable concentrates (EC), emulsions (EW), micro-emulsions (ME), Suspension concentrates (SC), oil-based suspension concentrates (OD), flowable suspensions (FS), wettable granules (WG), water-soluble granules (SG), wettable powders (WP), water-dispersible granule (WDG). water soluble powders (SP), granules (GR), encapsulated granules (CG), fine granules (FG), macrogranules (GG), dry flowables (DF), aqueous suspo-emulsions (SE), capsule suspensions (CS) and microgranules (MG).

In a preferred embodiment of the present invention, said herbicidal composition is in the form of oil dispersion (OD).

Oil dispersion (OD) formulation in the herbicidal combination has following advantages over other formulation:

• Better solubility for lipophilic ingredients – Ideal for herbicides with low water solubility.
• Improved weed uptake – Oils enhance penetration through waxy leaf surfaces.
• Greater rain fastness – Sticks better to plants, reducing wash-off after rain.
• Reduced spray drift – Heavier droplets minimize off-target movement.
• Uniform herbicide distribution – Ensures even coverage and better weed control.
• Lower solvent use – Environmentally safer with fewer organic solvents.
• Higher stability – More stable over time compared to water-based formulations.
• Reduced phytotoxicity – Less risk of damaging non-target plants.
The present invention provides a herbicidal composition which is a Ready to Use formulation (RTU). The ready to use formulation has various advantages over the tank mix of the active ingredients. The advantages associated with a ready to use composition include -very few or no inhalation hazards, easy handling, low chances of sedimentation, environmental safety, good efficacy, no or negligible phytotoxicity, lower transportation costs, and scientific practice as such a ready to use formulation is prepared after stability and compatibility studies.

In another embodiment, the present invention provides a process for the preparation of an herbicidal composition, comprising:
a. solubilizing dispersing agent, emulsifier and solvent with a high shear mixer to obtain a homogeneous mixture.
b. adding Imazethapyr technical, Flumioxazin technical to the homogenous mixture, followed by adding Diclosulam technical to obtain a homogenous mass;
c. grinding the homogenous mass in a sand mill to obtain a particle size less than 15µ (microns); and
d. mixing the material obtained in step (c) in a post mixer, followed by adding an anti-caking agent and mixing well to obtain an oil dispersion formulation.

In an embodiment of the present invention, Diclosulam is present in an amount ranging from 1-10% w/w, Flumioxazin is present in an amount ranging from 5-25% w/w, Imazethapyr is present in an amount ranging from 5-15% w/w and vegetable oil is present in an amount ranging from 0.05-2% w/w.

In a preferred embodiment of the present invention, the present invention provides a novel, stable, synergistic herbicidal composition comprising Diclosulam in an amount of 2.8% w/w, Flumioxazin in an amount of 7.5%, Imazethapyr in an amount of 7.5% w/w, Vegetable oil in an amount of 0.3% w/w and at least one agriculturally acceptable excipient.

In a preferred embodiment of the present invention, said at least one dispersing agent is vegetable oil ethoxylate.

In an embodiment of the present invention, said at least one dispersing agent is present in an amount ranging from 11-25% w/w.
In a preferred embodiment of the present invention, said at least one dispersing agent is present in an amount of 15% w/w.

In an embodiment of the present invention, said at least one emulsifier is selected from the group consisting of alkyl aryl EO-PO ethoxylates, Polysorbate 80/ Tween 80, Polysorbate 20/Tween 20, PEG400/PEG 200, Sorbitan hexa oleate/Sorbitan tri-oleate.

In a preferred embodiment of the present invention, said at least one emulsifier is alkyl aryl EO-PO ethoxylates.

In an embodiment of the present invention, at least one emulsifier is present in an amount ranging from 2-15% w/w.

In a preferred embodiment of the present invention, at least one emulsifier is present in an amount of 5% w/w.

In an embodiment of the present invention, said at least one anti-caking agent is selected from the group consisting of Silicon dioxide, Sodium-alumina silicate, Micro-crystalline cellulose, Lignin based anti-caking agent, Tri-calcium phosphate, hydrophobic silica.

In a preferred embodiment of the present invention, said at least one anti-caking agent is hydrophobic silica.

In an embodiment of the present invention, said at least one anti-caking agent is present in an amount ranging from 0.5-5% w/w.

In a preferred embodiment of the present invention, said at least one anti-caking agent is present in an amount of 1.50% w/w.

In an embodiment of the present invention, said at least one solvent is selected from the group consisting of Paraffinic oil, methyl oleate, methyl soyate, vegetable oil or methylated seed oil, oleic acid methyl ester, vegetable oil or methylated seed oil.

In a preferred embodiment of the present invention, said at least one solvent is oleic acid methyl ester.

In an embodiment of the present invention, said at least one solvent is present in amount ranging from 35-60% w/w.

In a preferred embodiment of the present invention, said at least one solvent is present in amount of 51.70% w/w.

In yet another aspect, the present invention provides a method for controlling undesirable weeds in soybean crop, said method comprising treating the locus at which the crop is growing or intended to be grown with a herbicidal composition comprising a) a herbicidally effective amount of Diclosulam, b) a herbicidally effective amount of Flumioxazin, c) a herbicidally effective amount of Imazethapyr and at least one agriculturally acceptable excipient.

In an embodiment of the present invention, a herbicidally effective amount of Diclosulam is present in an amount ranging from 1-10% w/w, a herbicidally effective amount of Flumioxazin is present in an amount ranging from 5-25% w/w, a herbicidally effective amount of Imazethapyr is present in an amount ranging from 5-15% w/w and at least one agriculturally acceptable excipient.

In yet another aspect, the present invention provides a method for controlling undesirable weeds in soybean crop, said method comprising treating the locus at which the crop is growing or intended to be grown with a herbicidal composition comprising a) a herbicidally effective amount of Diclosulam, b) a herbicidally effective amount of Flumioxazin, c) a herbicidally effective amount of Imazethapyr, d) vegetable oil and at least one agriculturally acceptable excipient.

In an embodiment of the present invention, a herbicidally effective amount of Diclosulam is present in an amount ranging from 1-10% w/w, a herbicidally effective amount of Flumioxazin is present in an amount ranging from 5-25% w/w, a herbicidally effective amount of Imazethapyr is present in an amount ranging from 5-15% w/w and vegetable oil is present in an amount ranging from 0.05-2% w/w and at least one agriculturally acceptable excipient.
In a preferred embodiment of the present invention, the present invention provides a novel, stable, synergistic herbicidal composition comprising Diclosulam in an amount of 2.8% w/w, Flumioxazin in an amount of 7.5%, w/w, Imazethapyr in an amount of 7.5% w/w, vegetable oil in an amount of 0.3% w/w and at least one agriculturally acceptable excipient.

In an embodiment of the present invention, said at least one agriculturally acceptable excipient is selected from the group consisting of at least one dispersing agent, at least one emulsifier, at least one anti-caking agent, at least one solvent and combination thereof.

In an embodiment of the present invention, the herbicidal composition actives exhibit synergistic effect in control of narrow leaved weeds and broad-leaved weeds in agricultural crops, particularly in soybean crop.

The herbicidal composition of the present invention has an outstanding herbicidal activity against monocotyledonous and dicotyledonous weeds, the tolerant, or cross-tolerant.

In an embodiment, the herbicidal composition of the present invention is effective in controlling a variety of broad and narrow-leaved weeds including, but not limited to, Echinocloa colonum (narrow leaved weeds), Eleusine indica (narrow leaved weeds), Digitaria sanguinalis (narrow leaved weeds), Dactyloctnium aegyptium (narrow leaved weeds), Commelina benghalensis (broad leaved weeds), Euphorbia hirta (broad leaved weeds), Digera arvensis (broad leaved weeds), Amaranthus viridis (broad leaved weeds).

Surprisingly, it has been reported by the present inventors that the presently disclosed herbicidal composition provides a broad-spectrum control of weeds at a much lower dosage of active ingredient combination as compared to solo active formulations, when combined.

The application of the presently disclosed herbicidal composition not only achieves an effective control of narrow-leaved weeds and broad-leaved weeds in Soybean crop and red gram but achieves that at a lower active dosage.

The foregoing description of the embodiments has been provided for purposes of illustration and not intended to limit the scope of the present invention. Individual components of a particular embodiment are generally not limited to that embodiment but are interchangeable. Such variations are not to be regarded as a departure from the present invention, and all such modifications need to be considered as within the scope of the present invention.

The present invention is further described in light of the following experiments which are set forth for illustrative purposes only and not to be construed as limiting the scope of the present invention. The following experiments can be scaled up to industrial/commercial scale and the results obtained can be extrapolated to industrial scale.

EXAMPLES
The examples below are given solely for the purpose of illustration and are not to be construed as limitations of the present invention, as many variations thereof are possible without departing from the spirit and scope of the invention.

Example 1: Preparation of herbicidal composition as oil dispersion

Table 1: Chemical composition of the present invention (in wt. percentage)
S.no. Percent composition with range- Component Composition (%w/w)
1 Diclosulam (100% basis) 02.80
2 Flumioxazin (100% basis) 07.50
3 Imazethapyr (100% basis) 07.50
4 Aerosil 200 (anti-caking agent) 01.50
5 Cis-9-octadecenoic acid (emulsifier) 09.00
6 Vegetable oil ethoxylate (dispersing agent) 15.00
7 Vegetable oil ester alkoxylate (emulsifier) 05.00
8 Oleic acid methyl ester (solvent) 51.70
Total 100

Preparation method of OD formulation is described below:
Step 1: Solubilizing dispersing agent, emulsifier and solvent (and vegetable oil) with a high shear mixer to obtain a homogeneous mixture.

Step 2: Adding Imazethapyr technical, Flumioxazin technical to the homogenous mixture, followed by adding Diclosulam technical to obtain a homogenous mass.
Step 3: Grinding the homogenous mass in a sand mill to obtain a particle size of less than 15 microns.

Step 4: Mixing the material obtained in step (3) in a post mixer, followed by adding an anti-caking agent and mixed well to obtain an oil dispersion formulation.

Example 2(a) Field evaluation of the bio-efficacy of the present herbicidal composition:
Location/Season/Crop:

The herbicidal trimix was tested for its bio-efficacy (in terms of percent weed control) against narrow leaved weeds and broad-leaved weeds in soybean. The trial was conducted during the kharif season 2024 at Indore, Madhya Pradesh on a local variety of Soybean.

Trial Layout
The plants were aligned with a spacing of 45cm between individual crop plants and a spacing of 20 cm between rows. The trial was laid out in a Random Block design consisting of a total of 11 treatments in three replications.

Climatic conditions:
The trial was conducted at a temperature of 33? under 82% relative humidity with no winds.

Application time:
The application of the herbicidal composition was carried out at a pre-emergence stage, 0-3 days after sowing.

Measured quantity of the chemical was added to required volume of water @ 375 lit. /ha for spray. The spray tank was filled with ½ the quantity of clean required volume of water and then the measured chemical (according to the dose) was added followed by the rest half quantity of water. The solution was stirred well before application. A Knapsack sprayer fitted with boom along with flood jet nozzle was used to apply the herbicidal composition.

Table 2: Treatment details:
Treatments Product a.i. (gm) /ha Dose (gm) /ha
T-1 UNTREATED
T-2 CH-2775 OD 21 + 56.25 + 56.25 750 ml
T-3 CH-2775 OD 23.1 + 61.9 + 61.9 825 ml
T-4 CH-2775 OD 28 + 75 + 75 1000 ml
T-5 CH- 27753 OD 21 + 56.25 + 56.25 + 2.25 750 ml
T-6 CH- 27753 OD 23.1 + 61.9 + 61.9 + 2.8 825 ml
T-7 CH- 27753 OD 28 + 75 + 75 + 3 1000 ml
T-8 Flumioxazin 50 % EC (CH/FMX/50 EC) 125 250
T-9 Imazethapyr 10% SL 100 1000
T-10 Pendimethalin 30%+ Imazethapyr 2% EC 900 + 60 3000 ml
T-11 Diclosulam 84% WDG 26 30.9

Note:
CH- 2775 OD Diclosulam 2.8% + Flumioxazin 7.5% + Imazethapyr 7.5% OD
CH- 27753 OD Diclosulam 2.8% + Flumioxazin 7.5% + Imazethapyr 7.5% + Vegetable oil 0.3% OD
T-8, T-9 and T-11 Solo products (regulatorily approved and commercially available)
T-10 Comparative market standard

Example 2: Evaluation of bio efficacy of the herbicidal composition against broad leaved and narrow leaved weeds

Weed count: A quadrate (0.5m × 0.5m) was placed at 3 randomly selected places in all the plots of the experimental field and the number of weed flora were counted uniformly at 14 Days and 28 days after application.

Weed control: The weed control was calculated based on no. of live weed flora at 14 Days and 28 days after application.

Percent weed control = WC – WT
…………. × 100
WC
Wherein,
WC= No. of weed in control plot
WT= No. of weed in treated plot

Observation:
Table 3: Comparative analysis of CH 2775 OD 14 day against NLW & BLW management of Soybean.
Product a.i./ha Echinochloa colonum Acalypha spp. Digera arvensis Amaranthus viridis
CH-2775 OD 21 + 56.25 + 56.25 72.84 d 75.17 cd 76.02 d 75.81 abcd
CH-2775 OD 23.1 + 61.9 + 61.9 79.87 bc 82.56 abc 82.59 cd 72.44 cd
CH-2775 OD 28 + 75 + 75 76.12 c 83.54 ab 83.24 cd 74.26 bcd
CH- 27753 OD 21 + 56.25 + 56.25 + 2.25 77.67 bc 76.51 bcd 85.64 ab 78.38 abc
CH- 27753 OD 23.1 + 61.9 + 61.9 + 2.8 91.48 a 89.23 a 93.14 a 87.57 a
CH- 27753 OD 28 + 75 + 75 + 3 91.85 a 89.74 a 92.97 ab 86.76 ab
Flumioxazin 50 % EC (CH/FMX/50 EC) 125 67.66 e 63.44 e 65.94 e 68.88 cd
Imazethapyr 10% SL 100 64.48 e 48.72 f 78.67 d 71.92 cd
Pendimethalin 30%+ Imazethapyr 2% EC 900 + 60 65.80 e 68.26 de 82.52 cd 64.87 d
Diclosulam 84% WDG 26 76.28 c 61.75 e 75.43 d 71.35 cd
CD (p=0.005) 3.72 5.81 3.28 3.02
CV (%) 5.71 4.59 4.21 2.53
synergy

As seen in table 3, treatment with Flumioxazin alone at a dosage of 125g ai/ha results in 67.66% control against Echinochloa colonum (broad leaved weeds), 63.44% control against Acalypha spp. (narrowed leaved weeds), 65.94% control against Digera arvensis (Broad leaved weeds) and 68.88% control against Amaranthus viridis (broad leaved weeds) after 14 days of application. Treatment with Imazethapyr alone a dosage of 100g ai/ha results in 64.48% control against Echinochloa colonum (broad leaved weeds), 48.72% control against Acalypha spp. (narrowed leaved weeds), 78.67% control against Digera arvensis (Broad leaved weeds) and 71.92% control against Amaranthus viridis (broad leaved weeds) after 14 days of application. Treatment with Diclosulam alone at a dosage of 26g ai/ha results in 76.28% control against Echinochloa colonum (broad leaved weeds), 61.75% control against Acalypha spp. (narrowed leaved weeds), 75.43% control against Digera arvensis (Broad leaved weeds) and 71.35% control against Amaranthus viridis (broad leaved weeds) after 14 days of application. However, unexpectedly and surprisingly, advantageously, the combination of Diclosulam, Flumioxazin, Imazethapyr and vegetable oil results in 91.48% control against Echinochloa colonum (broad leaved weeds), 89.23% control against Acalypha spp. (narrowed leaved weeds), 93.14% control against Digera arvensis (Broad leaved weeds) and 87.57% control against Amaranthus viridis (broad leaved weeds) after 14 days of application with reduced concentration of the active ingredients. Thus, the efficacy achieved with the combination is superior as compared to solo application of the active ingredients at a comparatively lower dosage.

Further, as seen in table 1, the combination of Diclosulam, Flumioxazin, Imazethapyr (without vegetable oil) results in 79.87% control against Echinochloa colonum (broad leaved weeds), 82.56% control against Acalypha spp. (narrowed leaved weeds), 82.59% control against Digera arvensis (Broad leaved weeds) and 72.44% control against Amaranthus viridis (broad leaved weeds) after 14 days of application. However, unexpectedly and surprisingly, advantageously, the combination of Diclosulam, Flumioxazin, Imazethapyr and vegetable oil results in 91.48% control against Echinochloa colonum (broad leaved weeds), 89.23% control against Acalypha spp. (narrowed leaved weeds), 93.14% control against Digera arvensis (Broad leaved weeds) and 87.57% control against Amaranthus viridis (broad leaved weeds) after 14 days of application. This led to the inference that addition of vegetable oil contributes to the synergy and better efficacy of the herbicidal combination.

Table 4. Comparative analysis of CH 2775 OD 28 day against NLW & BLW management of Soybean.
Product a.i./ha Echinochloa colonum Acalypha spp. Digera arvensis Amaranthus viridis
CH-2775 OD 21 + 56.25 + 56.25 81.58 bcd 74.09 bc 78.40 e 79.14 c
CH-2775 OD 23.1 + 61.9 + 61.9 80.04 cd 80.83 ab 85.11 cd 82.44 bc
CH-2775 OD 28 + 75 + 75 79.90 cd 81.35 ab 87.80 bc 84.70 ab
CH- 27753 OD 21 + 56.25 + 56.25 + 2.25 84.75 abc 84.97 a 90.54 ab 86.07 ab
CH- 27753 OD 23.1 + 61.9 + 61.9 + 2.8 89.34 ab 89.12 a 93.43 a 88.52 a
CH- 27753 OD 28 + 75 + 75 + 3 91.98 a 89.64 a 93.90 a 89.34 a
Flumioxazin 50 % EC (CH/FMX/50 EC) 125 66.70 ef 58.55 d 60.56 g 73.36 de
Imazethapyr 10% SL 100 62.71 f 43.01 e 75.12 e 70.49 e
Pendimethalin 30%+ Imazethapyr 2% EC 900 + 60 52.54 g 67.31 cd 83.37 d 64.34 f
Diclosulam 84% WDG 26 75.25 de 70.64 c 70.77 f 77.87 cd
CD (p=0.005) 7.01 8.02 3.73 4.10
CV (%) 6.87 7.41 3.02 3.71

As seen in table 4, treatment with Flumioxazin alone a dosage of 125g ai/ha results in 66.70% control against Echinochloa colonum (broad -leaved weeds), 58.55% control against Acalypha spp. (narrowed leaved weeds), 60.56% control against Digera arvensis (broad leaved weeds) and 73.36% control against Amaranthus viridis (broad leaved weeds) after 14 days of application. Treatment with Imazethapyr alone at a dosage of 100g ai/ha results in 62.71% control against Echinochloa colonum (broad leaved weeds), 43.01% control against Acalypha spp. (narrowed leaved weeds), 75.12% control against Digera arvensis (Broad leaved weeds) and 70.49% control against Amaranthus viridis (broad leaved weeds) after 14 days of application. Treatment with Diclosulam alone a dosage of 26g ai/ha results in 75.25% control against Echinochloa colonum (broad leaved weeds), 70.64% control against Acalypha spp. (narrowed leaved weeds), 70.77% control against Digera arvensis (broad leaved weeds) and 77.87% control against Amaranthus viridis (broad leaved weeds) after 14 days of application. However, unexpectedly and surprisingly, advantageously, the combination of Diclosulam, Flumioxazin, Imazethapyr and vegetable oil results in 89.34% control against Echinochloa colonum (broad leaved weeds), 89.12% control against Acalypha spp. (narrowed leaved weeds), 93.43% control against Digera arvensis (broad leaved weeds) and 88.52% control against Amaranthus viridis (broad leaved weeds) after 14 days of application with reduced concentration of the active ingredients. Thus, the efficacy achieved with the combination is superior to solo application of active ingredients at a comparatively lower dosage.

Further, as seen in table 1, the combination of Diclosulam, Flumioxazin, Imazethapyr (without vegetable oil) results in 80.04% control against Echinochloa colonum (broad leaved weeds), 80.83% control against Acalypha spp. (narrowed leaved weeds), 85.11% control against Digera arvensis (Broad leaved weeds) and 82.44% control against Amaranthus viridis (broad leaved weeds) after 14 days of application. However, unexpectedly and surprisingly, advantageously, the combination of Diclosulam, Flumioxazin, Imazethapyr and vegetable oil results in 89.34% control against Echinochloa colonum (broad leaved weeds), 89.12% control against Acalypha spp. (narrowed leaved weeds), 9.43% control against Digera arvensis (Broad leaved weeds) and 88.52% control against Amaranthus viridis (broad leaved weeds) after 14 days of application. This leads to the inference that addition of vegetable oil contributes to synergy and better efficacy of the herbicidal combination.

Example 4: Statistical Analysis (Synergistic Effect)
The data as shown in table 1 and 2 are recorded on various treatments of the present invention after proper tabulation were put to statistical analysis as per the randomized complete block method as described in Panse VG, Sukhatme PV. Statistical Methods for Agriculture workers ICAR, New Delhi; 1989 to draw the inferences of the study.

The significance of treatment effects was tested through variance ratio and the significance of difference between any two means was judged with the critical difference (CD) and multiple treatment comparison by Duncan’s Multiple Range test (DMRT) at 5 per cent level of significance was worked out.

The Critical Difference is the minimum difference between treatment means required for the difference to be considered statistically significant at a given confidence level (e.g., 95%). Duncan's Multiple Range Test (DMRT) is a statistical method used to compare group means and all pairs of means that are not significantly different. It's a post-hoc analysis method that's used after ANOVA to identify specific differences in means between groups.

Data for the treatment was put to statistical analysis by using R software. Comparison of both narrow and broad-leaved weeds mean incidence for levels across seasons carried out using DMRT are presented in tables 1 and 2. The differences in the % control differed significantly among the treatments on soybean crop for both narrow and broad-leaved weeds occurrence across the season. Significantly higher % control was seen in CH-27753 OD treatment as compared to other treatments. Therefore, these two treatments are statistically found to be at par (assigned the same letter). The variability is measured in terms of coefficient of variation (CV) was very low. The Coefficient of Variation (CV) is a standardized measure of the dispersion of a probability distribution or frequency distribution. It is often expressed as a percentage and is defined as the ratio of the standard deviation to the mean. It provides a standardized way to assess and compare the consistency of various treatments or experimental results.

In summary, the control percentage achieved by application of CH-27753 OD is significantly higher than the solo applications of the actives as shown by the statistical analysis above. Thus, it may be concluded that the combinations evaluated in the present invention display enhanced efficacy and synergy as compared to solo applications of actives.

Example 5: Evaluation of Phytotoxicity:
Visual observations were recorded at 10 and 20 days after application (DAA) of testing products. The parameters observed included leaf injury on tip/surface, necrosis, vein clearing, epinasty, hyponasty and wilting. The score scale (1-10) followed for leaf injury on tips/surface is given in Table below:

Table 5: Phytotoxicity symptoms scoring and rating for leaf injury on tip/surface:

Leaf injury on tips/surface Rating
0-10% 1
11-20% 2
21-30% 3
31-40% 4
41-50% 5
51-60% 6
61-70% 7
71-80% 8
81-90% 9
91-100% 10

Table 6: The Observations of phytotoxicity studies of various treatments

Product a.i./ha 5 DAA 10 DAA 15 DAA 20 DAA
CH-2775 OD 21 + 56.25 + 56.25 0 0 0 0
CH-2775 OD 23.1 + 61.9 + 61.9 0 0 0 0
CH-2775 OD 28 + 75 + 75 0 0 0 0
CH- 27753 OD 21 + 56.25 + 56.25 + 2.25 0 0 0 0
CH- 27753 OD 23.1 + 61.9 + 61.9 + 2.8 0 0 0 0
CH- 27753 OD 28 + 75 + 75 + 3 0 0 0 0
Flumioxazin 50 % EC (CH/FMX/50 EC) 125 0 0 0 0
Imazethapyr 10% SL 100 0 0 0 0
Pendimethalin 30%+ Imazethapyr 2% EC 900 + 60 0 0 0 0
Diclosulam 84% WDG 26 0 0 0 0

Observations were recorded at 5, 10, 15 and 20 days after various treatments/ applications.

As seen in Table 6, there was no phytotoxicity associated with the treatments, suggesting that the present herbicidal composition is crop safe. Thus, the present invention provides a stable, synergistic herbicidal composition comprising the combination of Diclosulam + Flumioxazin + Imazethapyr preferably along with Vegetable oil as synergist. Said herbicidal composition significantly enhances the economic value of the agricultural crops by eliminating the obnoxious weeds of both types (narrow leaved and broad leaved)

While the present specification discloses a concentration range across which surprising results could be seen, in particular, the combination of Diclosulam + Flumioxazin + Imazethapyr + Vegetable oil at concentration of 21g a.i/ha + 56.25g a.i/ha + 56.25g a.i/ha + 2.25g a.i/ha respectively were observed to show the best results in controlling the weeds of all types. Thus, there is a clear and significant enhancement in efficacy as compared to solo application of actives which is unexpected and surprising.
, Claims:We Claim:

1. A herbicidal composition comprising:
a. Diclosulam in an amount ranging from 1-10% w/w;
b. Flumioxazin in an amount ranging from 5-25% w/w;
c. Imazethapyr in an amount ranging from 5-15% w/w; and
d. at least one agriculturally acceptable excipient.

2. A herbicidal composition comprising:
a. Diclosulam in an amount ranging from 1-10% w/w;
b. Flumioxazin in an amount ranging from 5-25% w/w;
c. Imazethapyr in an amount ranging from 5-15% w/w;
d. Vegetable oil in an amount ranging from 0.05-2% w/w; and
e. at least one agriculturally acceptable excipient.

3. The herbicidal composition as claimed in claim 2, wherein said vegetable oil is selected from the group consisting of olive oil, sunflower oil, canola oil, coconut oil, safflower oil, corn oil, peanut oil, cottonseed oil, palm-kernel oil and soybean oil.

4. The herbicidal composition as claimed in claim 1 or 2, wherein said agriculturally acceptable excipient is selected from the group consisting of at least one dispersing agent, at least one emulsifier, at least one anti-caking agent, at least on solvent and combination thereof.

5. The herbicidal composition as claimed in claim 4, wherein said dispersing agent is present in an amount ranging from 11-25%w/w, said emulsifier is present in an amount ranging from 2-15%w/w, said anti-caking is present in an amount ranging from 0.5-5%w/w, said solvent is present in amount ranging from 35-60%w/w and combination thereof.

6. The herbicidal composition as claimed in claim 1 or 2, wherein said herbicidal composition comprises:
a. Diclosulam is present in an amount 2.8% w/w;
b. Flumioxazin is present in an amount of 7.5%w/w;
c. Imazethapyr is present in an amount of 7.5% w/w; and
d. at least one agriculturally acceptable excipient.

7. The herbicidal composition as claimed in claim 1 or 2, wherein said herbicidal composition comprises:
a. Diclosulam is present in an amount 2.8% w/w;
b. Flumioxazin is present in an amount of 7.5% w/w;
c. Imazethapyr is present in an amount of 7.5% w/w
d. vegetable oil is present in an amount of 0.3 w/w; and
e. at least one agriculturally acceptable excipient.

8. The herbicidal composition as claimed in any of the preceding claims, wherein said herbicidal composition is prepared in a form selected from the group comprising of water-soluble concentrates (SL), emulsifiable concentrates (EC), emulsions (EW), micro-emulsions (ME), Suspension concentrates (SC), oil-based suspension concentrates (OD), flowable suspensions (FS), water-dispersible granules (WDG), wettable granules (WG) water-soluble granules (SG), wettable powders (WP), water soluble powders (SP), granules (GR), encapsulated granules (CG), fine granules (FG), macro granules (GG), dry flowable (DF), aqueous Suspo-emulsions (SE), capsule suspensions (CS) and microgranules (MG).

9. The herbicidal composition as claimed in claim 8, wherein said herbicidal composition is in the form of an oil-dispersion (OD).

10. A process for the preparing an herbicidal oil dispersion, said process comprising
a. solubilizing dispersing agent, emulsifier, solvent and vegetable oil with a high shear mixer to obtain a homogeneous mixture;
b. adding Imazethapyr technical, Flumioxazin technical to the homogenous mixture, followed by adding Diclosulam technical to obtain a homogenous mass;
c. grinding the homogenous mass in a sand mill to obtain a particle size less than 15 microns; and
d. mixing the material obtained in step (c) in a post mixer, followed by adding an anti-caking agent and mixed well to obtain an oil dispersion formulation.

11. The process as claimed in claim 10, wherein a) Diclosulam is present in an amount ranging from 1-10% w/w; b) Flumioxazin is present in an amount ranging from 5-25% w/w; c) Imazethapyr is present in an amount ranging from 5-15% w/w and d) vegetable oil is present in an amount ranging from 0.05-2% w/w.

12. A method for controlling undesirable vegetation in soybean crop, said method comprising treating the locus at which the crop is growing or intended to be grown with a herbicidal composition comprising a) a herbicidally effective amount of Diclosulam, b) a herbicidally effective amount of Flumioxazin, c) a herbicidally effective amount of Imazethapyr and at least one agriculturally acceptable excipient.

13. A method for controlling undesirable vegetation in soybean crop, said method comprising treating the locus at which the crop is growing or intended to be grown with a herbicidal composition comprising a) a herbicidally effective amount of Diclosulam, b) a herbicidally effective amount of Flumioxazin, c) a herbicidally effective amount of Imazethapyr d) vegetable oil and at least one agriculturally acceptable excipient.

14. The method as claimed in claim 13, wherein a) herbicidally effective amount of Diclosulam is present ranging from 1-10% w/w, b) herbicidally effective amount of Flumioxazin is present ranging from 5-25% w/w, c) a herbicidally effective amount of Imazethapyr is present ranging from 5-15% w/w and d) vegetable oil is present ranging from 0.05-2% w/w.