DESC:FORM 2

THE PATENTS ACT 1970
(SECTION 39 OF 1970)
&
THE PATENT RULES, 2003

COMPLETE SPECIFICATION
(Section 10 and Rule 13)

SYNERGISTIC HERBICIDAL COMPOSITION OF SULFENTRAZONE AND PENDIMETHALIN

We, COROMANDEL INTERNATIONAL LIMITED,
an Indian company incorporated under the Companies Act, 1956, and validly existing under the Companies Act, 2013. Having its registered office at Coromandel House, Sardar Patel Road, Secunderabad – 500 003, Telangana, India

The following specification particularly describes the invention and the manner in which it is to be performed.

FIELD OF THE INVENTION
The present invention relates to a synergistic herbicidal composition comprising of sulfentrazone and pendimethalin. Particularly, the present invention relates to a suspo emulsion (SE) composition of sulfentrazone and pendimethalin along with suitable agrochemical adjuvants, and its preparation thereof.

BACKGROUND OF THE INVENTION
Herbicides are the most used method in our country and worldwide for the control of weed due to easy application, getting the results in a short time, having long lasting and powerful effect. They have nowadays increasingly become the most important and indispensable control method in agricultural production. They are used for a long time to increase the production of agricultural activities.

But the continued use of herbicides created many problems like weed resistance, shift weed in shift flora, and environment hazards. From this all-problems herbicide resistance is very serious problem in present time all over the world. The main reasons for resistance are lack of rotation of the herbicide and use of herbicides with long residue period. Herbicide resistance is a worldwide phenomenon and the number of resistant biotypes of weeds is increasing at an alarming rate. Currently there are 480 cases of herbicide resistance in 252 plant species. Herbicide resistance in weeds should be minimized because it is a major limiting factor of food security.

A proper knowledge of development and mechanism of resistance would help us with its management. Herbicide resistance problems are controlled with integrated weed management practices, including crop and herbicide rotations, herbicide combinations, and cultural, mechanical, and biological methods of weed control.

Hence, there is always a need for new active ingredients or new combinations of existing active ingredients to overcome the existing problems faced in the agricultural industry.

Active compounds having different mechanisms of action are combined to delay the generation of resistance and reduce the amount of application and prevention and treatment costs. Consequently, research is being conducted to produce herbicides and combinations of herbicides that are safer, that have better performance, that require lower dosages, that are easier to use, and that cost less.

Sulfentrazone is a broad-spectrum herbicide and is chemically known as N-{2,4-Dichloro-5-[4-(difluoromethyl)-3-methyl-5-oxo-4,5-dihydro-1H-1,2,4-triazol-1-yl] phenyl} methane sulfonamide. It acts by inhibiting the enzyme protoporphyrinogen oxidase in plants. PPO inhibitors at the herbicide site-of-action interfere with an enzyme involved in chlorophyll biosynthesis and lead to an accumulation of intermediates that are highly reactive when exposed to light resulting in membrane disruption.

It can be used both as pre-emergence and as a post emergence herbicide in the control of annual broadleaf weeds and yellow nutsedge in a variety of crops including soybeans, sunflowers, dry beans, and dry peas.

Pendimethalin is an herbicide of the dinitroaniline class used in preemergence and postemergence applications to control annual grasses and certain broadleaf weeds. It inhibits cell division and cell elongation for different crops including cereals (wheat, barley, rye, triticale), corn, soybeans, rice, potato, legumes, fruits, vegetables, nuts as well as lawns and ornamental plants and wheat, corn, soybeans, potatoes, cabbage, peas, carrots, and asparagus. It is used to control annual grasses and certain broadleaf weeds which interfere with growth, development, yield, and quality of agricultural and horticultural crops by competing on nutrients, water, and light.

Weed Technology, 19(4), 959-965, 2005 discloses weed controle efficacy of sulfentrazone alone or in combination with dimethenamid-P, pendimethalin, or imazethapyr for irrigated and dryland chickpea production. However, the said article does not mention the premix formulations and their use.

The present inventors developed a synergistic suspo emulsion (SE) composition of sulfentrazone and pendimethalin that possesses enhanced efficacy, and season-long weed control in soybean crop.

Suspo emulsions (SE) formulations are dust free, non-flammable, and have low phytotoxicity. In suspo emulsion (SE) formulations we can combine two active ingredients with different physical properties into one formulation. This can help in releasing the actives slowly into the soil, which improves the residual controle against the weeds.

Suspo emulsions (SE) formulations are stable for at least two years and have good storage stability at both low and high temperatures. They also have good dispersibility and suspensibility before and after storage at low and high temperatures.

The synergistic herbicidal composition of the present invention can control a wide range of undesired plants emerging in agricultural fields. It has a remarkable herbicidal activity when applied as sulfentrazone and pendimethalin in combination.

OBJECT OF THE INVENTION
One object of the present invention is to provide an herbicidal composition comprising of sulfentrazone and pendimethalin.

In another object of the present invention is to provide a synergistic suspo emulsion (SE) composition comprising sulfentrazone and pendimethalin in effective amounts, along with suitable agrochemical adjuvants.

In another object of the present invention is to provide synergistic, crop-selective herbicidal combination with broad-spectrum weed control.

In yet another object of the present invention is to provide a method for controlling undesired plants or inhibiting their growth, which comprises applying a herbicidally effective amount of the said composition to the undesired plants or to a place where they grow.

In yet another object of the present invention is to provide a suspo emulsions (SE) composition of sulfentrazone and pendimethalin for a pre-emergence herbicide in the control of seasonal broadleaf and grassy weeds in soybeans.

SUMMARY OF THE INVENTION
The present invention is to provide a synergistic herbicidal composition comprising sulfentrazone and pendimethalin.

One aspect of the present invention is to provide a synergistic suspo emulsion (SE) composition comprising as its active ingredients sulfentrazone present in a range from 5% to 15% (w/w), pendimethalin present in a range from 20% to 40% (w/w), and suitable agrochemical adjuvants.

In an aspect of the present invention, the suitable agrochemical adjuvants are selected from an anionic and non-ionic emulsifier, a wetting agent, a dispersing agent, an anti-freezing agent, a bactericide, a defoamer, a rheology modifier, a solvent, and a filler.

In another aspect of the present invention is to provide a process for the preparation of a synergistic suspo emulsion (SE) composition comprising of sulfentrazone, and pendimethalin.

In yet another aspect of the present invention is to provide an effective control against broad spectrum weed flora in soybean, at the lower dose rates of actives than their recommended dose rates.

In yet another aspect of the present invention is to provide a synergistic herbicidal composition, which can improve biological performance in single application and minimize occupational exposure and hazards.

In yet another aspect of the present invention is to provide a synergistic herbicidal composition, which demonstrates a high controlling effect with reduced environmental load and reduced cost of crop production as well as crop protection.

In yet another aspect of the present invention is to provide a synergistic herbicidal composition which provides single shot solution to farmers which can decrease the cost of application, save labor cost and therefore very economical.

DESCRIPTION OF THE INVENTION
The following detailed description is presented to enable any person skilled in the art to make and use the invention. For purposes of explanation, specific nomenclature is set forth to provide a thorough understanding of the present application. However, it will be apparent to one skilled in the art that these specific details are not required to practice the invention. Descriptions of specific applications are provided only as representative examples. The present application is not intended to be limited to the embodiments shown but is to be accorded the widest possible scope consistent with the principles and features disclosed herein.

It is to be noted that, as used in the specification, the singular forms "a", "an" and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to a composition containing “a compound” includes a mixture of two or more compounds. It should also be noted that the term “or” is generally employed in its sense including “and/or” unless the content clearly dictates otherwise.

As used herein, the terms "crops" and "vegetation" can include, for instance, dormant seeds, germinant seeds, emerging seedlings, plants emerging from vegetative propagules, immature vegetation, and established vegetation.

As used herein, the terms “herbicide” may be understood as a substance that is toxic to plants, used to destroy unwanted vegetation.

As used herein, the term “synergistic composition” may be understood to include effective combination of more than one agrochemical that allows the application of the said agrochemical in a much lower dosage, which results in a less dosage treatment for the crops.

As used herein, the term “agrochemical additives” may be understood to include a range of surfactants, dispersing agents, organic or inorganic pigments, solvents, de-solvents, defoamers, and emulsions, crystallization inhibitors, viscosity modifiers, suspending agents, dyes, antioxidants, foaming agents, light absorbers, mixing aids, neutralizers or pH adjusting substances and buffers, corrosion inhibitors, fragrances, wetting agents, absorption enhancers, micronutrients, plasticizers, lubricants, thickeners, anti-freezing agents, sterilization agents among others.

The expression of various quantities in terms of “% w/w” or “%” means the percentage by weight, relative to the weight of the total solution or composition unless otherwise specified

The herbicidal composition of the present invention may be formulated as capsule suspension (CS), dispersible concentrate (DC), dustable powder (DP), powder for dry seed treatment (DS), emulsifiable concentrate (EC), emulsifiable granule (EG), emulsion water in-oil (EO), emulsifiable powder (EP), emulsion for seed treatment (ES), emulsion oil-in-water (EW), flowable concentrate for seed treatment (FS), granules (GR), micro-emulsion (ME), oil-dispersion (OD), oil miscible flowable concentrate (OF), oil miscible liquid (OL), oil dispersible powder (OP), suspension concentrate (SC), suspension concentrate for direct application (SD), suspo-emulsion (SE), water soluble granule (SG), soluble concentrate (SL), spreading oil (SO), water soluble powder (SP), water soluble tablet (ST), ultra-low volume (ULV) suspension, tablet (TB), ultra-low volume (ULV) liquid, water dispersible granules (WG or WDG), wettable powder (WP), water dispersible powder for slurry seed treatment (WS), water dispersible tablet (WT), a mixed formulation of CS and SC (ZC), a mixed formulation of CS and SE (ZE), and a mixed formulation of CS and EW (ZW).

In an embodiment of the present invention provides a synergistic herbicidal composition comprising sulfentrazone and pendimethalin.

In an embodiment of the present invention provides a synergistic suspo emulsion (SE) composition comprising as its active ingredients sulfentrazone present in a range from 5% to 15% (w/w), pendimethalin present in a range from 20% to 40% (w/w), and suitable agrochemical adjuvants.

According to the present invention, the suitable agrochemical adjuvants are selected from an anionic and non-ionic emulsifier, a wetting agent, a dispersing agent, an anti-freezing agent, a bactericide, a defoamer, a rheology modifier, a solvent, and a filler.

According to the present invention, an anionic emulsifier is selected form the group comprising of calcium dodecylbenzene sulfonate, calcium salt of benzene sulphonic acid linear alkyl derivative, calcium salt of linear dodecyl benzene sulphonic acid and isobutyl alcohol, and non-ionic emulsifier is selected form the group comprising of tristyrylphenol ethoxylates, castor oil ethoxylates (36 & 40 moles), and combination thereof, present in a range from 1% to 10% (w/w).

According to the present invention, the wetting agent is selected from the group comprising of alcohol ethoxylates, sodium lauryl sulphate, and sodium alkyl naphthalene sulphonate blend, present in a range from 1% to 5% (w/w).

According to the present invention, the dispersing agent is selected from the group comprising of acrylic copolymer, sodium lignosulphonates, and modified styrene acrylic polymer, present in a range from 1% to 5% (w/w).

According to the present invention, the anti-freezing agent is propylene glycol present in a range from 1% to 5% (w/w).

According to the present invention, the bactericide is 1,2-benzisothiazalin-3-one, present in an amount of 0.01% to 0.2% (w/w).

According to the present invention, the defoamer is silicone emulsion, present in a range from 0.1% to 1% (w/w).

According to the present invention, the rheology modifier is xanthan gum, present in an amount of 5% to 15% (w/w).

According to the present invention, the solvent is selected from solvent C9 (aromatic solvent naphtha), and N, N-Dimethyl decylamine, present in a range from 30% to 40% (w/w).

According to the present invention, the filler is distilled water, present in Q.S.

In another embodiment of the present invention provides a process for the preparation of a suspo emulsion (SE) composition comprising of sulfentrazone, and pendimethalin.

The composition achieves improved biological activity by enhancing overall control of weeds over a shorter period. Additional benefits of using the herbicidal composition of the present invention includes reduced risk of occupational hazard, lower cost of application, better cost: benefit ratio to the end user, reduced fuel, and labor cost, saving in applicator’s time and loss caused by mechanical damage to the crop and soil.

The present compositions can be applied to weeds by using conventional ground or aerial dusters & sprayers, and by other conventional means known to those skilled in the art.

The following examples describe the nature of the invention which are given only for the purpose of illustrating the present invention in more detail and are not limitative and relate to solutions, which have been particularly effective on bench scale.

EXAMPLES:
The illustrative embodiments show the composition of sulfentrazone + pendimethalin in suspo emulsion (SE) formulations:

Example-1: Sulfentrazone 9.29% + Pendimethalin 28.57% SE
S. No. Ingredients Function Quantity (%w/w)
1. Sulfentrazone Active ingredient 9.29
2. Pendimethalin Active ingredient 28.57
3. Tristyrylphenol ethoxylates Emulsifier 1.5
4. Calcium dodecylbenzene sulfonate Emulsifier 1.5
5. Solvent C9
(Aromatic Solvent Naphtha) Solvent 35.0
6. Acrylic copolymer Dispersing Agent 3.0
7. Alcohol ethoxylates Wetting Agent 2.0
8. 1, 2-Benzisothiazol-3(2H)-one Bactericide 0.1
9. Silicone emulsion Defoamer 0.5
10. Xanthan gum Rheology Modifier 15.0
11. Propylene glycol Anti-freezing agent 5.0
12. Distilled water Filler Q.S.

Procedure of preparation of Sulfentrazone 9.29% + Pendimethalin 28.57% SE Composition:
Step 1: Preparation of EW (A)
• An EW was prepared by incorporating sulfentrazone technical in suitable solvent (solvent C9) followed by addition of anionic (calcium dodecylbenzene sulfonate) and non-anionic emulsifiers (tristyrylphenol ethoxylates).
• Required quantity of antifreezing agent (propylene glycol) and filler (water) were added to the resultant mixture and kept under stirring.
Step 2: Preparation of Aqueous Slurry (B)
• Required quantity of dispersing agent (acrylic copolymer) and wetting agents (Alcohol ethoxylates) were added to propylene glycol followed by addition of defoamer (Silicone emulsion) and bactericide (1,2-benzisothiazalin-3-one).
• Required quantity of pendimethalin technical was added to the above and mixed under stirring.
• post addition of water, stir the mixture for homogenization for about 1 hour (the mixture should be thoroughly homogenized).
Step 3:
• In this step, EW (A) portion was added to the Aqueous Slurry (B) and mixed under stirring.
Step 4: Wet Milling of Slurry
• Pass the wet slurry from Vessel No. 1 through Dyno-Mill at temperature less than 30 °C and collect material in Vessel No. 2 (Post-Mixer).
• Maintain continuous Stirring in both the vessels to avoid the sedimentation.
• Submitting the sample to Quality Control Department to check the Particle Size distribution (PSD). The PSD of the material should be d90 < 5 µ. If the d90 is higher than > 5 µ then grind the mixture further till the PSD value complies the specification.
Step 5: Preparation of 2.0% Gel (Gel Suspension)
• Add 2.0 parts by weight of rheology modifier (Xanthan gum) in 4.0 parts by weight of Propylene glycol then add this slurry into 94.0 parts by weight of distilled water and stir the mixture until it gets lumps free homogeneous mixture.
• Keep this gel as such for 4-5 hours to get a translucent homogeneous gel.
Step 6: Gelling of Wet Milled Slurry.
• Add required quantity of Gel (prepared above) to the wet slurry in Vessel No 2 and stir the mixture for ~2 h for homogenization.
• Submit the sample for total Quality Control for complete analysis.
Step 7: Packing the sample in COEX container.

Example-2: Sulfentrazone 9.29% + Pendimethalin 28.57% SE
S. No. Ingredients Function Quantity (%w/w)
1. Sulfentrazone Active ingredient 9.29
2. Pendimethalin Active ingredient 28.57
3. Tristyrylphenol ethoxylates Emulsifier 1.5
4. Calcium salt of benzene sulphonic acid linear alkyl derivative Emulsifier 1.5
5. Solvent C9
(Aromatic Solvent Naphtha) Solvent 35.0
6. Acrylic copolymer Dispersing Agent 3.0
7. Alcohol ethoxylates Wetting Agent 2.0
8. 1, 2-Benzisothiazol-3(2H)-one Bactericide 0.1
9. Silicone emulsion Defoamer 0.5
10. Xanthan gum Rheology Modifier 15.0
11. Propylene glycol Anti-freezing agent 5.0
12. Distilled water Filler Q.S.

The process for manufacture of composition is similar to the procedure as described in example 1.

Example-3: Sulfentrazone 5.5 %+ Pendimethalin 21.5%SE
S. No. Ingredients Function Quantity (%w/w)
1. Sulfentrazone Active ingredient 5.5
2. Pendimethalin Active ingredient 21.5
3. Solvent C9
(Aromatic Solvent Naphtha) Solvent 40.0
4. Castor Oil Ethoxylates 40moles Emulsifier 2.5
5. Calcium dodecyl benzene sulphonate Emulsifier 2.5
6. Sodium ligno sulphonates Dispersing Agent 5.0
7. Sodium lauryl sulphate Wetting Agent 3.0
8. 1, 2-Benzisothiazol-3(2H)-one Bactericide 0.01
9. Silicone emulsion Defoamer 0.1
10. Xanthan Gum Rheology Modifier 5.0
11. Propylene Glycol Anti-freezing agent 1.0
12. Distilled water Filler Q.S.
The process for manufacture of composition is similar to the procedure as described in example 1.

Example-4: Sulfentrazone 13.8 %+ Pendimethalin 35.2%SE
S. No. Ingredients Function Quantity (%w/w)
1. Sulfentrazone Active ingredient 13.8
2. Pendimethalin Active ingredient 35.2
3. N, N-Dimethyl decylamine Solvent 30.0
4. Castor oil ethoxylates 36 moles Emulsifier 5.0
5. Calcium salt of linear dodecyl benzene sulphonic acid and isobutyl alcohol Emulsifier 5.0
6. Sodium ligno sulphonates Dispersing Agent 1.0
7. Sodium alkyl naphthalene sulphonate blend Wetting Agent 1.0
8. 1, 2-Benzisothiazol-3(2H)-one Bactericide 0.1
9. Silicone emulsion Defoamer 1.0
10. Xanthan Gum Rheology Modifier 5.0
11. Propylene Glycol Anti-freezing agent 1.0
12. Distilled water Filler Q.S.

The process for manufacture of composition is similar to the procedure as described in example 1.

Example 5: Efficacy study of Sulfentrazone 9.29% + Pendimethalin 28.57% in Suspo emulsion (SE) form:

SYNERGY STUDIES:
The synergistic pesticidal action of the inventive mixtures calculated by Colby’s formula as follows:

Appropriate analysis of plant response to herbicide combination is critical in determining the type of activity observed. The most widely used model is the one Gowing* derived and Colby** modified. Gowing described a mathematical formula for calculating the predicting response values for herbicide mixtures. He suggested the expected (E) percent inhibition of growth induced by herbicide A plus herbicide B is as follows, *(Jerry Flint et al, 1988) ***

AB
Expected (E) = A + B –
100

Where:
A = Percent weed control by herbicide A.
B = Percent weed control by herbicide B.

When the percentage of pesticidal control observed for the combination is greater than the expected percentage, there is a synergistic effect. (Ratio of O/E > 1, means synergism observed.)

Reference:
*Gowing, D. P. 1960. Comments on tests of herbicide mixtures. Weeds 8:379–391.
**Colby, S. R. 1967. Calculating synergistic and antagonistic responses of herbicide combinations. Weeds 15:20–22
*** Jerry Flint et al, 1988. Analyzing Herbicide Interactions: A Statistical Treatment of Colby's Method. Weed Technology 2: 304-309.

FIELD AND SYNERGY STUDIES:
Soybean is an important rainy season crop of India. In India, it is grown on an area of 108.83 lakh ha with an annual production of 104.36 lakh million tons. Successful weed control is the most important factor for fruitful soybean production because losses due to weeds have been one of the major limiting factors in soybean production. Weeds compete with crop for light moisture and nutrients. Being a rainy season crop soybean faces severe weed competition during crop growth, resulting in a loss of about 40-60% of the potential yield. Traditionally, weed control in India has been largely dependent on manual weeding. However, increased labour scarcity and costs are encouraging farmers to adopt herbicides.

Field studies were conducted to compare the weed controlling activity of the combination of sulfentrazone and pendimethalin. The active ingredient sulfentrazone in the combination, belongs to chemical family “N-phenylphthalimides” with mode of action Protoporphyrinogen oxidase (PPO) and Pendimethalin herbicide belongs to chemical class “Dinitroaniline” with microtubule Assembly inhibitor mode of action. Combination has the potential of controlling the cross-spectrum weeds (broad leaf weeds & grassy weeds) in soybean at the pre-emergence (0-3 DAS) application timing. Both the molecules are safe to soybean when applied at their recommended dose rate in pre-emergence (0-3 DAS) application timing.

The weed control activity of the individual herbicides of the invention and their combinations were evaluated on weeds such as Acalypha indica, Commelina benghalensis, Commelina communis, Digera arvensis, Echinochloa colona and Ischaemum rugosum. Trials were conducted with randomized block design with net plot size of 5m x 6 m. Each trial was replicated four times and conducted under GEP guidelines. Spraying was done with manual operated backpack knapsack sprayer with 300 L of water spray volume per hectare at pre-emergence (0-3 DAS) application timing. Such field trials were carried out at various locations to generate independent data, the locations were chosen randomly across India.

Visual observations were recorded on percent weed control for individual weeds on whole plot basis at 30 days after application. These observations are to be taken from the entire plot.

The herbicide combinations, application rates, plant species tested, and results are given in the following tables:

Table 1: Demonstrates synergy on weeds using the combination of sulfentrazone and pendimethalin. The field trials were carried out in India at various locations. The percentage efficacy was calculated after 30 days of application. The target weeds were Commelina benghalensis and Commelina communis and the results are recorded below.

Active Dose (GAH) % Weed Control of Commelina benghalensis % Weed Control of Commelina communis
Expected Observed Expected Observed
Sulfentrazone 39.6% SC 325 80 75
Pendimethalin 30% EC 999.9 10 10
Sulfentrazone 9.29% + Pendimethalin 28.57% SE 325 + 999.9 82 90 77.5 85
Ratio of O/E 1.09 1.09

The results in table 1 clearly demonstrate synergistic effect of sulfentrazone 9.29% + pendimethalin 28.57% SE against weeds like, Commelina benghalensis and Commelina communis. The higher ratio of the observed and the expected efficacy clearly demonstrates the synergistic effect of the combination.

Table 2: Demonstrates synergy on weeds using the combination of sulfentrazone and pendimethalin. The field trials were carried out in India at various locations. The percentage efficacy was calculated after 30 days of application. The target weeds were Echinochloa colonum and Ischaemum rugosum and the results are recorded below.

Active Dose (GAH) % Weed Control of Echinochloa colonum % Weed Control of Ischaemum rugosum
Expected Observed Expected Observed
Sulfentrazone 39.6% SC 325 20 10
Pendimethalin 30% EC 999.9 80 80
Sulfentrazone 9.29% + Pendimethalin 28.57% SE 325 + 999.9 84 90 82 85
Ratio of O/E 1.07 1.03

The results in table 2 clearly demonstrates synergistic efficacy of sulfentrazone 9.29% + pendimethalin 28.57% SE against weeds like Echinochloa colonum and Ischaemum rugosum. The higher ratio of the observed and the expected efficacy clearly demonstrates the synergistic effect of the combination.

Table 3: Demonstrates synergy on weeds using the combination of sulfentrazone and pendimethalin. The field trials were carried out in India at various locations. The percentage efficacy was calculated after 30 days of application. The target weeds were Dinebra retroflexa and Brachiaria erusiformis and the results are recorded below.

Active Dose (GAH) % Weed Control of Dinebra retroflexa % Weed Control of Brachiaria erusiformis
Expected Observed Expected Observed
Sulfentrazone 39.6% SC 325 30 40
Pendimethalin 30% EC 999.9 85 85
Sulfentrazone 9.29% + Pendimethalin 28.57% SE 325 + 999.9 89.5 97 91 98
Ratio of O/E 1.08 1.07

The results in table 3 clearly demonstrate synergistic efficacy of sulfentrazone 9.29% + pendimethalin 28.57% SE against weeds like Dinebra retroflexa and Brachiaria erusiformis. The higher ratio of the observed and the expected efficacy clearly demonstrates the synergistic effect of the combination.

Table 4: Demonstrates synergy on weeds using the combination of sulfentrazone and pendimethalin. The field trials were carried out in India at various locations. The percentage efficacy was calculated after 30 days of application. The target weeds were Acalypha indica and Digera arvensis and the results are recorded below.

Active Dose (GAH) % Weed Control of Acalypha indica % Weed Control of Digera arvensis
Expected Observed Expected Observed
Sulfentrazone 39.6% SC 325 90 90
Pendimethalin 30% EC 999.9 0 20
Sulfentrazone 9.29% + Pendimethalin 28.57% SE 325 + 999.9 90 92 92 95
Ratio of O/E 1.02 1.03

The results in table 4 clearly demonstrate synergistic efficacy of sulfentrazone 9.29% + pendimethalin 28.57% SE against weeds like Acalypha indica and Digera arvensis. The higher ratio of the observed and the expected efficacy clearly demonstrates the synergistic effect of the combination. ,CLAIMS:We claim:
1. A synergistic suspo emulsion (SE) composition comprising sulfentrazone present in a range from 5% to 15% (w/w), pendimethalin present in a range from 20% to 40% (w/w), and suitable agrochemical adjuvants.

2. The composition as claimed in claim 1, wherein the suitable agrochemical adjuvants are selected from an anionic and non-ionic emulsifier, a wetting agent, a dispersing agent, an antifreezing agent, a bactericide, a defoamer, a rheology modifier, a solvent, and a filler.

3. The composition as claimed in claim 2, wherein the anionic emulsifier is selected form the group comprising of calcium dodecylbenzene sulfonate, calcium salt of benzene sulphonic acid linear alkyl derivative, calcium salt of linear dodecyl benzene sulphonic acid and isobutyl alcohol, and non-ionic emulsifier is selected form the group comprising of tristyrylphenol ethoxylates, Castor oil ethoxylates (36 & 40 moles), and combination thereof, present in a range from 1% to 10% (w/w).

4. The composition as claimed in claim 2, wherein the wetting agent is selected from the group comprising of alcohol ethoxylates, sodium lauryl sulphate, and sodium alkyl naphthalene sulphonate blend, present in a range from 1% to 5% (w/w).

5. The composition as claimed in claim 2, wherein the dispersing agent is selected from the group comprising of acrylic copolymer, sodium ligno sulphonates, and modified styrene acrylic polymer, present in a range from 1% to 5% (w/w).

6. The composition as claimed in claim 2, wherein the antifreezing agent is propylene glycol present in a range from 1% to 5% (w/w), wherein the bactericide is 1,2-benzisothiazalin-3-one, present in an amount of 0.01% to 0.2% (w/w).

7. The composition as claimed in claim 2, wherein the rheology modifier is xanthan gum, present in an amount of 5% to 15% (w/w).

8. The composition as claimed in claim 2, wherein the defoamer is Silicone emulsion, present in a range from 0.1% to 1% (w/w).

9. The composition as claimed in claim 2, wherein the solvent is selected from solvent C9 (aromatic solvent naphtha), and N, N-Dimethyl decylamine, present in a range from 30% to 40% (w/w).

10. The composition as claimed in claim 2, wherein the filler is distilled water, present in Q.S.

Date this Sixth (6th) day of August, 2024.

__________________________________
Dr. S. Padmaja
Agent for the Applicant
IN/PA/883