DESC:Synergistic Herbicidal Combination of Bispyribac Sodium and Pretilachlor
FIELD OF THE INVENTION
The present invention relates to a synergistic herbicidal composition comprising the combination of bispyribac sodium and chloroacetamide herbicide in EC / WDG / SC / SL / OD / OS / Solid Granules and other formulations in different percentages. More precisely, the subject of the present invention is a synergistic herbicidal composition based on a combination of bispyribac sodium and pretilachlor optionally with at least one agriculturally acceptable excipient which will facilitate in the preparation of desired formulations. The present invention also relates to the process for the preparation of synergistic herbicidal composition thereof and use of this combination for contending weeds and protecting the crop from being affected with such weeds during its growth.
BACKGROUND OF THE INVENTION
Crop protection is the practice of protecting the crop yields from pests, weeds, plant diseases, and other organisms that damage agricultural crops, which is critical from early stages of crop development. Preventing weed growth in the entire crop cycle, i.e., from root development to maturing crop, leads to increased crop quality and yield. The control of weeds is extremely important in achieving high crop efficiency. Unwanted vegetation causes significant damage to vegetables, fields, cereal, fruit and other crops that compete with crops for nutrients, water, and sunlight leading to reduction in productivity, yield and quality of the crops. Herbicides help to minimize this damage by controlling the growth of weeds. The use of two or more appropriate active ingredient combinations in specific dose ratios leads to synergism in crop protection. In addition to this, often highly destructive weeds can be difficult to control and may develop resistance to commercial herbicides. Many products are commercially available for these purposes, but there is still a continues need to develop new herbicidal combinations which are more effective, less costly, less toxic, environmentally safer and have different sites of action.
The biggest challenge in field of crop protection is to reduce the dosage rate of active ingredients to diminish or circumvent environmental or toxicological effects without compromising on effective crop protection against weeds, in addition to long lasting and broad-spectrum of weed control. Another challenge is to reduce the excessive application of solo chemical compounds or herbicides which invariably helps in rapid selection of weeds and aid in developing natural or adapted resistance against the active compound in question.
Therefore, it is indeed necessary to use the herbicide combinations in lower doses, fast acting with the different mode of action that can provide long lasting control against broad spectrum weed control and check the resistance development in weeds. The composition should have high synergistic action, no cross resistance to existing herbicides, avoid excess loading of the toxicant to the environment and negligible impact to environmental safety. A need also exists for synergistic herbicidal compositions which could be physico-compatible formulations in the form of storage stable, safely packed, ready to use formulation.
OBJECT OF THE INVENTION
The principal object of the present invention is to provide an herbicide mixture or combination which solves at least one of the major problems discussed above like reducing the dosage rate, broadening the spectrum of activity, or combining activity with prolonged weed control and resistance management with improved environmental safety by reducing toxicity and residue deposit in soil and in crops.
The details of one or more embodiments of this disclosure are set forth in the accompanying description below and other features, objects, and advantages will be apparent from the description and the claims.
DESCRIPTION OF THE INVENTION
The present disclosure / specification refers to a synergistic herbicidal composition and the process for the preparation for crop protection.
The term “combination” can be replaced with the words “mixture” or “composition” defined or refers to as combining two or more active ingredients formulated in desired formulations.
The term “pesticide” as used in this specification refers to a substance or mixture of substances intended for preventing, destroying, repelling, or mitigating any pest or weeds which causes damage to the crop. Herbicides, insecticides, and fungicides are mainly used as pesticides which control weeds and insect pests and disease-causing pathogens respectively that eventually leads to high yield of crops.
The term “Herbicides” as used in this specification refers to a substance or mixture of substances used to kill, control or eliminate unwanted plants or vegetation, commonly known as weeds that cause economic damage to crops and ornamental plants.
The term “synergism” as used in this specification refers to the interaction between two or more active compounds or other factors to produce a combined effect greater than the sum of their separate effects. The present invention involves the mixture of two active ingredients which has increased efficacy when compared to individual use and admixture of those components.
Conventional herbicides have typical spectrums and effects, are limited to certain weeds only and their controlling activities are sometimes poor and not satisfactorily maintained for prolonged period, and those satisfactory herbicidal effects cannot be practically achieved. Even though some herbicides may bear satisfactory herbicidal effects, they require improvements in respect of environment & health safety and are also demanded to achieve a high herbicidal effect at a smaller dosage and lack of resistance management.
We found that this objective in part or complete can be achieved by the combination of active compounds defined at the outset. Thus, the present inventors have intensively studied to solve these problems and have found that by combining herbicide composition having bispyribac sodium and pretilachlor in different formulation and percentages have astonishing effects of controlling weeds and by reducing amount of dosage than in a case of using an active compound alone and admixture of those compounds.
Therefore, the present invention provides a novel synergistic herbicide composition having bispyribac sodium and pretilachlor and purpose thereof. The synergy of herbicidal composition has the main effective components of bispyribac sodium and pretilachlor. This herbicidal composition acts by interference / inhibition of acetolactate synthase, ALS (acetohydroxyacid synthase AHAS) and cell division inhibitor, respectively and can generate efficient synergism as a pre-emergent or early-post or post-emergent herbicide and can enable broad spectrum satisfactory weed control and protect the rice crop from sedges, grasses, and broad leaf weeds for prolonged period at lower dose with no phytotoxic effect. It also prevents the weeds from rejuvenation and further regeneration.
This combination can be developed in the form of Emulsifiable Concentrates (EC), Dispersible Concentrates (DC), Oil Dispersions (OD), Suspension Concentrates (SC), Soluble Liquids (SL), Suspoemulsion (SE), Emulsion Concentrates (EW), Microemulsions, Wettable Powders (WP), Water-Dispersible Granules (WG), Soluble Powders (SP), Granules (GR), Oil Solutions (OS), Aqueous Suspensions (AS), Aqueous Solutions (AS), Microencapsulated Suspensions (ME), and Microencapsulated Emulsions (MEC), mixed formulation of Suspension Concentrate and Capsule Suspension (ZC) and other conventional formulation and with different percentages and can be used for foliar applications or soil applications. This herbicidal combination can also effectively check the weeds and resistance development of weeds in various crops.
The present invention comprises the mixture of two active ingredients which are bispyribac sodium and chloroacetamide herbicide are described herein thereof.
Bispyribac sodium is a selective, systemic, and broad spectrum post-emergent herbicide that absorbed by foliage and roots and moves throughout the plant tissue and works by interfering with production of a plant enzyme necessary for growth i.e., acetolactate synthase (ALS). It is used to control grasses, sedges, and broad-leaved vulnerable weeds. Bispyribac sodium is also practically non-toxic and does not bioaccumulate in the soil.
The chloroacetamides are one of the most widely used groups of herbicides, which are characterized by an excellent efficacy against many annual grass weeds and mainly used in pre-emergent and early post-emergent treatment. The herbicidal activity of the chloroacetamides is due to their capability to inhibit the biosynthesis of nonsphingolipid very-long-chain fatty acids (VLCFAs), resulting in a lack of lipids, proteins, and lignin for the weeds.
Pretilachlor (IUPAC name: 2-chloro-N-(2,6-diethylphenyl)-N-(2-propoxyethyl) acetamide; molecular formula: C17H26ClNO2; molecular weight: 311.8 g/mol) is chloroacetamide herbicide having broad-spectrum of systemic activity recommended for the control of annual grasses, sedges, and broad leaf weeds. The mode of action of pretilachlor involves inhibiting the biosynthesis of fatty acids in the target weeds. Specifically, it interferes with the acetyl-CoA carboxylase enzyme, which plays a crucial role in fatty acid synthesis. By inhibiting acetyl -CoA carboxylase enzyme, pretilachlor controls the growth and development of weeds.
Pretilachlor has both foliar and soil application and it controls both newly emerged weeds and weeds emerging from seeds. It effectively protects the rice and paddy crop from early phase for longer period and promotes the development of the crops.
The first embodiment of the present invention provides a synergistic herbicidal composition comprising:
bispyribac; and
chloroacetamide herbicide.
First aspect of the first embodiment, the chloroacetamide herbicide is selected from the group comprising acetochlor, alachlor, allidochlor, amidochlor, butachlor, butenachlor, delachlor, diethatyl, dimethachlor, dimethenamid, ethachlor, ethaprochlor, metazachlor, metolachlor, pethoxamid, pretilachlor, propachlor, propisochlor, prynachlor, terbuchlor, thenylchlor, and xylachlor.
Second aspect of the first embodiment, synergistic herbicidal composition comprising a combination of bispyribac sodium and chloroacetamide herbicide; wherein bispyribac sodium and chloroacetamide herbicide are present in the weight ratio of (1-80): (1-80); preferably in the ratio of (1-40): (1-40).
The second embodiment of the present invention provides a synergistic herbicidal composition comprising:
bispyribac;
chloroacetamide herbicide; and
at least one agriculturally acceptable excipient.
First aspect of the second embodiment, the chloroacetamide herbicide is selected from the group comprising acetochlor, alachlor, allidochlor, amidochlor, butachlor, butenachlor, delachlor, diethatyl, dimethachlor, dimethenamid, ethachlor, ethaprochlor, metazachlor, metolachlor, pethoxamid, pretilachlor, propachlor, propisochlor, prynachlor, terbuchlor, thenylchlor, and xylachlor; preferably pretilachlor.
Second aspect of the second embodiment, synergistic herbicidal composition comprising a combination of bispyribac sodium and pretilachlor; wherein bispyribac sodium and pretilachlor are present in the weight ratio of (1-80): (1-80); preferably in the ratio of (1-40): (1-40).
The third aspect of the second embodiment, agriculturally acceptable excipient selected from but not limited to the group comprising liquid medium, surfactant, stabilizer, anti-freezing agent, antifoaming agent, anticaking agent, dispersing agent, adjuvant, and antibacterial agent. These are selected according to the respective types of formulation requirements, and which will facilitate in the preparation different formulations.
Further aspect of the second embodiment, liquid medium acts as a carrier for the active ingredients and provides a stable environment for suspension selected form but not limited to water and organic solvents.
Further aspect of the second embodiment, surfactant includes wetting agent and emulsifier.
Further aspect of the second embodiment, emulsifier includes anionic emulsifiers, cationic emulsifiers, non-ionic emulsifiers, amphoteric emulsifiers, phospholipids, and glyceryl esters.
Further aspect of the second embodiment, anionic emulsifiers selected from but not limited to sodium lauryl sulfate (SLS), sodium dodecyl benzenesulfonate (SDBS), alkyl sulfates, and calcium alkyl benzene sulfonate.
Further aspect of the second embodiment, cationic emulsifiers selected from but not limited to cetyl trimethyl ammonium bromide (CTAB), and stearalkonium chloride.
Further aspect of the second embodiment, non-ionic emulsifiers selected from but not limited to polysorbate, sorbitan monolaurate, ethoxylates, sorbitan monooleate, and polyaryl sulfate esters.
Further aspect of the second embodiment, amphoteric emulsifiers selected from but not limited to cocamidopropyl betaine, lauramidopropyl betaine, ethoxylated nonylphenol (nonylphenol ethoxylate), ethoxylated sorbitan esters, and ethoxylated fatty alcohols.
Further aspect of the second embodiment, wetting agent selected from but not limited to alkyl aryl sulfonates, alkyl phenol ethoxylates, alkyl polyglucosides, polyethylene glycol esters, polysorbate, polyethylene oxide (PEO), ethoxylated fatty alcohols, ethoxylated vegetable oils, propylene glycol esters, sodium lauryl sulfate, and block copolymers selected from the but not limited to styrene-butadiene block copolymer (SBS), butyl based block copolymer, poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) (PEO-PPO-PEO), polystyrene-poly(ethylene oxide) (PS-PEO), poly(butadiene)-poly(styrene) (PB-PS), poly(methyl methacrylate)-poly(butadiene)-poly(methyl methacrylate) (PMMA-PB-PMMA), poly(caprolactone)-poly(ethylene glycol)(PCL-PEG), and poly(ethylene glycol)-poly(propylene glycol)-poly(ethylene glycol) (PEG-PPG-PEG).
Further aspect of the second embodiment, stabilizer includes antioxidant, chelating agent, pH adjusters, UV absorber, stabilizing polymers, and inert.
Further aspect of the second embodiment, stabilizer selected from group vegetable and seed oils selected from but not limited to soybean oil, sunflower seed oil, coconut oil, peanut oil, corn oil, castor oil, palm oil, rapeseed oil, safflower oil, olive oil, corn oil, cottonseed oil, linseed oil, tung oil and sesame oil, and oxidized forms of the above oils.
Further aspect of the second embodiment, anti-freezing agent selected from but not limited to ethylene glycol, propylene glycol, glycerol, calcium chloride, sodium acetate, potassium acetate and urea.
Further aspect of the second embodiment, antifoaming agents selected from but not limited to silicone-based antifoams, polyethylene glycol-based antifoams, mineral oil-based antifoams, ethylene glycol-based antifoams, polysorbate-based antifoams, dimethicone-based antifoams, polypropylene glycol-based antifoams, vegetable oil-based antifoams, alkyl siloxane-based antifoams, and fatty acid-based antifoams.
Further aspect of second embodiment, anticaking agent selected from silica-based compounds includes silicon dioxide (silica), precipitated silica (amorphous form of silicon dioxide), calcium silicate, magnesium stearate, sodium aluminosilicate, potassium aluminium silicate, tricalcium phosphate, sodium ferrocyanide, calcium carbonate, diatomaceous earth, and sodium bicarbonate.
Further aspect of the second embodiment, dispersing agents selected from but not limited to polyethylene glycol, polysorbate, poly acrylate, poly(methyl methacrylate), polyvinyl alcohol, poly ethoxylated alcohol, poly ethoxylated fatty acids, polyacrylic acid, polyvinylpyrrolidone, alkyl sulfonates, aryl sulfonates, sodium tripolyphosphate, sodium dodecyl sulfate, sodium lignosulfonate, sodium carboxymethyl cellulose, hydroxypropyl methylcellulose, sorbitan esters (e.g., sorbitan monolaurate, sorbitan monooleate), gum arabic and carbomer and/or their comb polymers.
Further aspect of the second embodiment, adjuvant includes but not limited to spreader, colorant, modifier, sticker, penetrant, drift control agent, buffering agent, thickener, compatibility agent, binders, and safener.
Further aspect of second embodiment, inert filler selected from but not limited to kaolin clay, attapulgite clay, bentonite, montmorillonite, acid white clay, pyrophyllite, talc, diatomaceous earth and calcite, china clay, corn rachis powder, walnut husk powder, urea, calcium carbonate, ammonium sulfate, and silicon oxides.
Further aspect of the second embodiment, thickener selected from but not limited to polysaccharides / carboxymethyl cellulose / bentonite clay, hydroxy propyl cellulose montmorillonite, bentonite, magnesium aluminium silicate, and attapulgite.
Further aspect of the second embodiment, binder or sticking agent selected from but not limited to methyl cellulose, ethyl cellulose, hydroxy propyl methyl cellulose, hydroxy propyl cellulose, sodium carboxy methyl cellulose, polyvinyl pyrrolidone, polyethylene glycol, polyvinyl alcohol, and polymethacrylates.
Further aspect of the second embodiment, colorant is water soluble anionic blue dye.
Further aspect of the second embodiment, antibacterial agent selected from but not limited to triclosan, triclocarban, clotrimazole, miconazole, copper-based compounds, chlorothalonil, benzisothiazolin-3-one (BIT), 5-chloro-2-methyl-4-isothiazolin-3-one, 2-methyl-4-isothiazolin-3-one (MIT), octylisothiazolinone (OIT), and dodecylbenzenesulfonic acid and sodium salt (DBSA).
The third embodiment of the present invention provides a synergistic herbicidal composition comprising:
bispyribac sodium;
pretilachlor;
liquid medium;
stabilizer;
anti-caking agent;
inert;
colorant; and
binder / sticking agent.
The first aspect of the third embodiment, synergistic herbicidal composition comprising a combination of bispyribac sodium and pretilachlor; wherein bispyribac sodium and pretilachlor are present in the weight ratio of (1-80): (1-80); preferably in the ratio of (1-40): (1-40).
The second aspect of the third embodiment, agriculturally acceptable excipient selected from but not limited to the group comprising liquid medium, stabilizer, anti-caking agent, inert filler, adjuvant, colorant and binders or sticking agent. These are selected according to the respective types of formulation requirements, and which will facilitate in the preparation different formulations.
Further aspect of the third embodiment, liquid medium acts as a carrier for the active ingredients and provides a stable environment for suspension selected form but not limited to water and organic solvents; preferably water.
Further aspect of the third embodiment, stabilizers selected from group vegetable and seed oils selected from but not limited to soybean oil, sunflower seed oil, coconut oil, peanut oil, corn oil, castor oil, palm oil, rapeseed oil, safflower oil, olive oil, corn oil, cottonseed oil, linseed oil, tung oil and sesame oil and oxidized forms of the above oils; preferably epoxidized soyabean oil.
Further aspect of third embodiment, anticaking agent selected from silica-based compounds includes silicon dioxide (silica), precipitated silica (amorphous form of silicon dioxide), calcium silicate, magnesium stearate, sodium aluminosilicate, potassium aluminium silicate, tricalcium phosphate, sodium ferrocyanide, calcium carbonate, diatomaceous earth, and sodium bicarbonate; preferably precipitated silica.
Further aspect of third embodiment, inert filler selected from but not limited to kaolin clay, attapulgite clay, bentonite, montmorillonite, acid white clay, pyrophyllite, talc, diatomaceous earth and calcite, china clay, corn rachis powder, walnut husk powder, urea, calcium carbonate, ammonium sulfate, and silicon oxides; preferably silicon oxides.
Further aspect of the third embodiment, adjuvant includes but not limited to spreader, colorant, modifier, sticker, penetrant, drift control agent, buffering agent, thickener, compatibility agent, binder, and safener.
Further aspect of the third embodiment, colorant is water soluble anionic blue dye.
Further aspect of the third embodiment, binder / sticking agent selected from but not limited to methyl cellulose, ethyl cellulose, hydroxy propyl methyl cellulose, hydroxy propyl cellulose, sodium carboxy methyl cellulose, polyvinyl pyrrolidone, polyethylene glycol, polyvinyl alcohol, and polymethacrylates; preferably polyvinyl alcohol.
The fourth embodiment of the present invention provides a synergistic herbicidal composition comprising:
bispyribac sodium; and
pretilachlor.
First aspect of the fourth embodiment, synergistic herbicidal composition comprising a combination of bispyribac sodium and pretilachlor; wherein bispyribac sodium and pretilachlor are present in the at a weight ratio of (1-80): (1-80); preferably in the ratio of (1-40): (1-40).
Second aspect of the fourth embodiment, the composition of the fourth embodiment comprising at least one agriculturally acceptable excipient thereof which is / are used in preparation desired formulation.
Further aspect of the fourth embodiment, the composition of the fourth embodiment is formulated as granules (GR).
Further aspect of the fourth embodiment, the composition of the fourth embodiment is formulated as emulsions in water (EW).
Further aspect of the fourth embodiment, the composition of the fourth embodiment is formulated as micro-emulsion (ME)
Further aspect of the fourth embodiment, the composition of the fourth embodiment is formulated as oil dispersion (OD).
Further aspect of the fourth embodiment, the composition of the fourth embodiment is formulated as oil-miscible liquids (OL).
The fifth embodiment of the present invention provides a synergistic herbicidal composition comprising:
bispyribac sodium;
pretilachlor;
water;
epoxidized soyabean oil;
precipitated silica;
silicon oxides;
blue dye; and
polyvinyl alcohol.
First aspect of the fifth embodiment, synergistic herbicidal composition comprising a combination of bispyribac sodium and pretilachlor; wherein bispyribac sodium and pretilachlor are present in the weight ratio of (1-80): (1-80); preferably in the ratio of (1-20): (1-20); more preferably in the ratio of (1-10): (1-10).
Further aspect of the fifth embodiment, the composition of fifth embodiment is formulated as granules (GR).
Another embodiment of the present invention provides a process for the preparation of an herbicidal formulation comprising:
add water, bispyribac and pretilachlor to the above mixture and stir for 30-60 minutes to get homogenous mixture.
add stabilizer, colorant, sticking / binding agent to the above vessel under continuous stirring.
spray the above solution on silicon oxides slowly with continuous stirring along with the addition of anticaking agent up to get homogenous granules.
pack the formulation and seal it.
Another embodiment of the present invention, the synergistic herbicidal composition of present invention used in defined dose rations shows effective weed control in broad spectrum of weeds and increases the crop yield, quality, lesser dose rations and shows no phytotoxicity compared to single components, admixture of those two component and other available market standards. By this the herbicidal composition of present invention archives synergistic effect along with economical value product and improved environmental safety by reducing toxicity and residue deposit in soil and in crops.
Another embodiment of the present invention, a method of controlling annual grasses, sedges and broad leaf weeds comprising synergistic herbicidal composition applying to the location of weed in effective amount.
Another embodiment of the present invention, the herbicidal composition obtained from the present used to control broadleaf weeds, sedges, and annual grasses in paddy, wheat, pineapple, sugarcane, maize, and bananas crops. It is also used in multiple crops, including cereal and grains, grasses, IVM and grape orchards and thereof.
Another embodiment of the present invention, the herbicidal composition obtained from the present shows synergistic effects of better weed control with minimum herbicidal resistance and improved crop yield and quality.
Another embodiment of the present invention, the synergistic herbicidal composition can be applied to pre-emergence, early post-emergence, or post-emergence stages by conventional spraying methods, such as foliar application etc., over the target areas of weeds or vegetation at same time avoiding excessive drift or runoff of the composition securing thorough coverage.
Advantages of the Present Invention:
The synergistic herbicidal composition of present invention can be used in pre-emergence, early post-emergence, or post-emergence stages for effective weed control to increase the yield of crops compare to single component of composition and market standards. This will help the farmers in controlling weeds in the entire crop cycle.
The novel, innovative and synergistic herbicidal composition of present invention provides better weed management in agricultural and non-agricultural fields.
The synergistic herbicidal composition of present invention is effective against broader spectrum of unwanted weeds compared to single component and market standards without any environmental pollution.
The synergistic herbicidal composition of the present invention avoids or reduces the damage of crops and shows no phytotoxicity.
The best mode of carrying present invention is described in the below given examples. These examples are merely for illustrative purposes only, not to determine the scope of the invention and in no way limit the scope or spirit of the present invention.

EXAMPLES:
EXAMPLE 1: GRANULES (GR) FORMULATION OF SYNERGISTIC HERBICIDAL COMPOSITION OF THE PRESENT INVENTION:
TABLE 1:
S. No Ingredient Weight/ Weight %
1 Bispyribac sodium 0.2
2 Pretilachlor 4.8
3 Water 0.5
4 Epoxidized soyabean oil 0.5
5 Precipitated silica 4
6 Blue dye 0.05
7 Polyvinyl alcohol 0.6
8 Silicon oxides QS
Total 100
EXAMPLE 2: PROCESS FOR PREPARATION OF GRANULE (GR) FORMULATION OF SYNERGISTIC HERBICIDAL COMPOSITION OF THE PRESENT INVENTION
Add water, bispyribac sodium and pretilachlor into the blender in the above-mentioned ratios and mix well until a homogenous mixture is obtained. Add stabilizer, colorant and sticking agent into the above mixture and mix well. Spray the above solution on the sand slowly with continuous stirring and at the same time add batch quantity of anticaking agent slowly with continuous stirring up to get homogenous granules.
EXAMPLE 3: BIO EFFICACY AND PHYTOTOXICITY TESTS OF THE PRESENT INVENTION
Presently to evaluate the efficacy of bispyribac sodium 0.2% + pretilachlor 4.8% formulation against grasses, sedges, and broad-leaved weeds as post emergent herbicide in paddy and to test phytotoxicity of the molecule on the crop have been conducted. Bispyribac sodium 0.2% + pretilachlor 4.8% is tested at three dose levels viz., low, medium, and high along with the sole molecule as individual treatments and their efficiency comparison is done with the current competitive market standards. To justify the results, the overall effect and other parameters are calculated over untreated check. The paddy crop is first divided into plots for each treatment and replicated three times following randomized block design. The spraying method followed was foliar application with the help of a knapsack sprayer and the sprays are done in paddy as post emergent herbicide.
Method of Observations:
No. of weed /1 sq meter area: Take 4 sticks/pipes of 1 meter each and tie their ends/joints so that they make a square shape. Before taking the weed counts, the square should be placed in the treated plot randomly and the number of weed species in the 1metre area is counted.
Take the observation of individual weed species to understand or draw conclusions on the efficacy of the herbicide against individual weeds. The observations were taken at 15, 30 and 45 days after application (DAA).
Take the observation on the crop safety of the herbicide i.e., phytotoxicity / softener observation of herbicide after application at 5 and 10 days after application.
Parameters of Observations:
The weeds controlled in each treatment are calculated as percent weed controlled over untreated or controlled plot. The percent weed control is calculated by the following formula: –
% weed control = (No.of weeds in control plot-No.of weeds in treated plot )/(No.of weeds in control plot)× 100
The effect of these herbicides when applied on paddy is assessed based on the yield (tons per hectare).

Results:
The different types and species of weeds found in this experiment in paddy field were enlisted below:
Grasses: Echinocloa crusgalli and Cyanodon dactylon
Broad Leaved Weeds: Ludwigia parviflora, Alternanthera sessilis and Marselia quadrifolia
Sedges: Cyprus iria and Fimbristylis miliaceae
Table 1. Efficacy of bispyribac sodium 0.2%+ pretilachlor 4.8% GR formulation against grassy weeds:
Treatments Dose /
ha
(gm / L) 15 DAA 30 DAA 45 DAA Average Percent
Weed
Control
E.c C.d E.c C.d E.c C.d E.c C.d E.c C.d
Pretilachlor 4.8% + bispyribac sodium 0.2% GR 8,000 25 14 0 0 5 3 10.00 5.67 85.29 85.47
Pretilachlor 4.8% + bispyribac sodium 0.2% GR 10000 23 12 0 0 0 0 7.67 4.00 88.73 89.74
Pretilachlor 4.8% + bispyribac sodium 0.2% GR 12000 18 8 0 0 0 0 6.00 2.67 91.18 93.16
Pretilachlor 50% EC 1000 38 12 23 8 27 10 29.33 10.00 56.86 74.36
bispyribac sodium 10% EC 250 36 23 12 6 10 5 19.33 11.33 71.57 70.94
Bensulfuron methyl 0.6% + Pretilachlor 6% GR 10000 44 23 13 2 11 8 22.67 11.00 66.67 71.79
Pretilachlor 6% + Pyrazosulfuron ethyl 0.15% GR 10000 48 18 12 2 9 9 23.00 9.67 66.18 75.21
Untreated control -- 61 32 65 38 78 47 68.00 39.00 0.00 0.00
DAA – Days after application; E. c – Echinochloa colonum; C.d – Cyanodon dactylon
The grassy weed population is taken post application as this is a post emergent herbicide evaluation experiment. After the application of different herbicide treatments, the herbicide combination treatments bispyribac sodium 0.2% + pretilachlor 4.8% GR when applied at 12000 g/ha and 10000 g/ha showed maximum reduction in weed population. At 15 days after application (DAA) the weed population recorded was 18 weeds/m2 (E. colonum), 8 weeds/m2 (C. dactylon) followed by 0 weeds/m2 in case of both the species viz., E. colonum, C. dactylon at both 30 DAA, 45 DAA respectively. The average weeds population after the entire experiment was recorded lowest in bispyribac sodium 0.2% + pretilachlor 4.8% GR @ 12000 g/ha with 6 weeds/m2 (E. colonum), 2.67 weeds/m2 (C. dactylon) followed by bispyribac sodium 0.2% + pretilachlor 4.8% GR @ 10000 g/ha with 7.67 weeds/m2 (E. colonum), 4 weeds/m2 (C. dactylon). The percentage of weed control recorded in all the treatments proved that bispyribac sodium 0.2% + pretilachlor 4.8% GR when applied at 12000 g/ha were showing maximum weed control 91.18% (E. colonum), 93.16% (C. dactylon) and bispyribac sodium 0.2% + pretilachlor 4.8% GR @ 10000 g/ha showed 88.73% (E. colonum), 89.74% (C. dactylon) of weed control. There by proving that these molecules when applied in combination at the doses of 12000, 10000 gm/ha showed synergistic activity and weeds control superior to market standard. Even the treatment bispyribac sodium 0.2%+ pretilachlor 4.8% GR when applied at 8000 g/ha (lowest dose of the herbicide combination) also showed greater percentage of weed control of 85.29% (E. colonum) and 85.47% (C. dactylon) which is also superior to the market standard. While, the market standards recorded an average weed population of 22.67 weeds/m2 with 66.67% weed control (E. colonum), 11 weeds/m2 with 71.79% weed control (C. dactylon) in case of bensulfuron methyl 0.6% + pretilachlor 6% GR @ 10000 g/ha followed by pretilachlor 6% + pyrazosulfuron ethyl 0.15% GR @ 10000 g/ha recorded an average weed population of 23 weeds/m2 with 66.18% weed control (E. colonum), 9.67 weeds/m2 with 75.21% weed control (C. dactylon).
Table 2. Efficacy of Bispyribac sodium 0.2% + Pretilachlor 4.8% GR formulation against broad leaved weeds:
Treatments Dose / ha
(gm / L) 15 DAA 30 DAA 45 DAA Average Percent Weed Control
L.p A.s M.q L.p A.s M.q L.p A.s M.q L.p A.s M.q L.p A.s M.q
Bispyribac sodium 0.2% + pretilachlor 4.8% GR 750 71 28 31 0 0 0 0 0 0 23.67 9.33 8.00 84.01 86.14 88.29
Bispyribac sodium 0.2% + pretilachlor 4.8% GR 1000 54 24 28 0 0 0 0 0 0 18.00 8.00 9.33 87.84 88.12 86.34
Bispyribac sodium 0.2% + pretilachlor 4.8% GR 1250 39 15 24 0 0 0 0 0 0 13.00 5.00 10.33 91.22 92.57 84.88
Pretilachlor 50% EC 1000 113 34 29 51 10 12 22 9 14 62.00 17.67 18.33 58.11 73.76 73.17
Bispyribac sodium 10% EC 250 112 35 27 60 14 9 23 8 15 65.00 19.00 17.00 56.08 71.78 75.12
Bensulfuron methyl 0.6% + pretilachlor 6% GR 10000 114 39 26 82 19 19 24 14 22 73.33 24.00 22.33 50.45 64.36 67.32
Pretilachlor 6% + pyrazosulfuron ethyl 0.15% GR 10000 117 42 29 102 24 24 25 16 29 81.33 27.33 27.33 45.05 59.41 60.00
Untreated control - 129 46 44 149 67 70 166 89 91 148.00 67.33 68.33
L. p - Ludwigia parviflora; A.s - Alternanthera sessilis; M.q – Marselia quadrifolia
The broad-leaved weeds species identified in the paddy field were Ludwigia parviflora, Alternanthera sessilis and Marselia quadrifolia. After the application of different herbicide treatments, the herbicide combination bispyribac sodium 0.2% + pretilachlor 4.8% GR when applied at 12000 g/ha and 10000 g/ha showed maximum reduction in weed population. At 15 days after application (DAA) the weed population recorded was 39 weeds/m2 (L. parviflora), 15 weeds/m2 (A. sessilis) and 24 weeds/m2 (M. quadrifolia) followed by 0 weeds/m2 in case of the three species viz., Ludwigia parviflora, Alternanthera sessilis and Marselia quadrifolia at both 30 DAA, 45 DAA respectively. The average weeds population after the entire experiment was recorded lowest in bispyribac sodium 0.2% + pretilachlor 4.8% GR@ 12000 g/ha with 13 weeds/m2 (L. parviflora), 5 weeds/m2 (A. sessilis) and 8 weeds/m2 (M. quadrifolia) followed by bispyribac sodium 0.2% + pretilachlor 4.8% GR@ 10000 g/ha with 18 weeds/m2 (L. parviflora), 8 weeds/m2 (A. sessilis) and 9.33 weeds/m2 (M. quadrifolia). The percentage of weed control recorded in all the treatments proved that bispyribac sodium 0.2% + pretilachlor 4.8% GR when applied at 12000 g/ha were showing maximum weed control 91.22% (L. parviflora), 92.57% (A. sessilis), 88.29% (M. quadrifolia) and bispyribac sodium 0.2% + pretilachlor 4.8% GR@ 10000 g/ha showed 87.84% (L. parviflora), 88.12% (A. sessilis), 86.34% (M. quadrifolia) of weed control there by proving that these molecules when applied in combination at the doses of 12000, 10000 gm/ha showed synergistic activity and weeds control superior to market standard. Even the treatment bispyribac sodium 0.2% + pretilachlor 4.8% GR when applied at 8000 g/ha (lowest dose of the herbicide combination) also showed greater percentage of weed control of 84.01% (L. parviflora), 86.14% (A. sessilis), 84.88% (M. quadrifolia) which is also superior to the market standard. While, the market standards recorded an average weed population of 73.33 weeds/m2 with 50.45% weed control (F. parviflora), 24 weeds/m2 with 64.36% weed control (A. sessilis) and 22.33 weeds/m2 with 67.32% weed control (M. quadrifolia) in case of bensulfuron methyl 0.6% + pretilachlor 6% GR @ 10000 g/ha followed by pretilachlor 6% + pyrazosulfuron ethyl 0.15% GR @ 10000 g/ha recorded an average weed population of 81.33 weeds/m2 with 45.05% weed control (F. parviflora), 27.33 weeds/m2 with 59.41% weed control (A. sessilis) and 27.33 weeds/m2 with 60% weed control (M. quadrifolia).
Table 3. Efficacy of bispyribac sodium 0.2% + pretilachlor 4.8% GR formulation against sedges:
Treatments Dose /
ha
(gm / L) 15 DAA 30 DAA 45 DAA Average Percent
Weed
Control
C.i F.m C.i F.m C.i F.m C.i F.m C.i F.m
Bispyribac sodium 0.2% + pretilachlor 4.8% GR 750 38 19 0 0 3 5 13.67 8.00 83.67 82.98
Bispyribac sodium 0.2% + pretilachlor 4.8% GR 1000 33 17 0 0 0 0 11.00 5.67 86.85 87.94
Bispyribac sodium 0.2% + pretilachlor 4.8% GR 1250 24 14 0 0 0 0 8.00 4.67 90.44 90.07
Pretilachlor 50% EC 1000 50 20 29 12 22 11 33.67 14.33 59.76 69.50
Bispyribac sodium 10% EC 250 51 23 13 7 9 4 24.33 11.33 70.92 75.89
Bensulfuron methyl 0.6% + pretilachlor 6% GR 10000 56 25 14 5 10 8 26.67 12.67 68.13 73.05
Pretilachlor 6% + pyrazosulfuron ethyl 0.15% GR 10000 60 27 12 5 8 7 26.67 13.00 68.13 72.34
Untreated control - 64 31 92 43 95 67 83.67 47.00 - -
C.i – Cyperus iria; F.m – Fimbristylis miliaceae
The sedges found in the paddy in this experiment belong to two species i.e., Cyperus iria, Fimbristylis miliaceae. After the application of different herbicide treatments, the herbicide combination treatments bispyribac sodium 0.2% + pretilachlor 4.8% GR when applied at 12000 g/ha and 10000 g/ha showed maximum reduction in weed population. At 15 days after application (DAA) the treatment bispyribac sodium 0.2% + pretilachlor 4.8% GR when applied at 12000 g/ha recorded 24 weeds/m2 (C. iria), 14 weeds/m2 (F. miliaceae) and there after 0 weeds/m2 were recorded at 30, 45 DAA respectively. When bispyribac sodium 0.2% + pretilachlor 4.8% GR applied at 10000 g/ha recorded 33 weeds/m2 (C.iria), 17 weeds/m2 (F. miliaceae) at 15 DAA, followed which 0 weeds/m2 were recorded at both 30 DAA, 45 DAA in both species. The average weeds population after the entire spraying was recorded the lowest in bispyribac sodium 0.2% + pretilachlor 4.8% GR@ 12000 g/ha with 8 weeds/m2 (C. iria), 4.67 weeds/m2 (F. miliaceae) and followed by bispyribac sodium 0.2% + pretilachlor 4.8% GR@ 10000 g/ha with 11 weeds/m2 (C. iria), 5.67 weeds/m2 (F. miliaceae) which were performing superior to market standards. The percentage of weed control recorded in all the treatments proved that bispyribac sodium 0.2% + pretilachlor 4.8% GR when applied at 12000 g/ha were showing maximum weed control 90.44% (C. iria), 90.07% (F. miliaceae) and at 10000 g/ha recorded 86.85% (C. iria), 87.94% (F. miliaceae) of weed control. The weeds when treated with market standards recorded low percent weed control viz.,68.13% (C. iria), 73.05% (F. miliaceae) in bensulfuron methyl 0.6% + pretilachlor 6% GR @ 10000 g/ha followed by pretilachlor 6% + pyrazosulfuron ethyl 0.15% GR @ 10000 g/ha recorded with 68.13% (C. iria), 72.34% (F. miliaceae) weed control. Thereby proving that these molecules are superior to market standard. Even the treatment bispyribac sodium 0.2% + pretilachlor 4.8% GR when applied at 8000 g/ha (lowest dose of the herbicide combination) also showed greater percentage of weed control of 83.67% (C. iria), 82.98% (F. miliaceae) which is also superior to the market standard.
Table 4. Phytotoxicity of bispyribac sodium 0.2% + pretilachlor 4.8% GR formulation on paddy:
Treatments Days Visual Rating Scale
Yellowing Necrosis Wilting Vein
Clearing Leaf tip / Margin Dying Stunting / Dwarfing
Bispyribac sodium 0.2% + pretilachlor 4.8% GR @ 8000 g/ha 5 0 0 0 0 0 0
10 0 0 0 0 0 0
Bispyribac sodium 0.2% + pretilachlor 4.8% GR @10000 g/ha 5 0 0 0 0 0 0
10 0 0 0 0 0 0
Bispyribac sodium 0.2% + pretilachlor 4.8% GR @12000 g/ha 5 0 0 0 0 0 0
10 0 0 0 0 0 0
Pretilachlor 50% EC @1000 ml/ha 5 0 0 0 0 0 0
10 0 0 0 0 0 0
Bispyribac sodium 10% EC @250 ml/ha 5 0 0 0 0 0 0
10 0 0 0 0 0 0
Bensulfuron methyl 0.6% + pretilachlor 6% GR@10000 g/ha 5 0 0 0 0 0 0
10 0 0 0 0 0 0
Pretilachlor 6% + pyrazosulfuron ethyl 0.15% GR @10000 g/ha 5 0 0 0 0 0 0
10 0 0 0 0 0 0
Untreated Control 5 0 0 0 0 0 0
10 0 0 0 0 0 0
The phytotoxicity effect of the herbicide combination i.e., bispyribac sodium 0.2% + pretilachlor 4.8% GR on paddy was tested after 5 and 10 days after spraying. The crop was checked for symptoms like yellowing, necrosis, wilting, vein clearing, leaf tip or leaf margin dying and stunting or dwarfing of plants. After thorough observations, it could be concluded that the crop did not show any symptoms of phytotoxicity. Therefore, the present herbicide combination can be considered a safe combination.
Table 5. Effect of bispyribac sodium 0.2% + pretilachlor 4.8% GR formulation on paddy yield:
Treatments Dose / Ha
(gms / ml) Cane Yield
(T/Ha)

Bispyribac sodium 0.2%+ pretilachlor 4.8% GR 8000 47.5
Bispyribac sodium 0.2%+ pretilachlor 4.8% GR 10000 50.8
Bispyribac sodium 0.2%+ pretilachlor 4.8% GR 12000 52.6
Pretilachlor 50% EC 1000 43
Bispyribac sodium 10% EC 250 39.6
Bensulfuron methyl 0.6% + pretilachlor 6% GR 10000 35.2
Pretilachlor 6% + pyrazosulfuron ethyl 0.15% GR 10000 32
Untreated control - 27
The yield among different herbicide treatments showed that bispyribac sodium 0.2% + pretilachlor 4.8% GR when applied at 12000 g/ha, 10000 g/ha and 8000 g/ha recorded the highest yield of 52.60 t/ha, 50.80 t/ha and 47.50 t/ha which shows that the herbicidal combination when applied at three different doses viz., high, medium, and low have similar positive effect on the cane yield of paddy. While the same herbicides when applied alone i.e., pretilachlor 50% EC @ 1000 ml/ha gave 43 t/ha, bispyribac sodium 10% EC @ 250 ml/ha gave 39.60 t/ha. It is evident based on the results the herbicide combination has a synergistic effect when applied together especially improved the crop quality in the current case.
It is to be understood that this disclosure is not limited to a particular compositions or specific constituents, which can, of course, vary and that the terminology used herein is for the purpose of describing embodiments only and is not intended to be limiting the scope of the invention. As used in this specification and the appended claims, the singular forms "a," "an," and "the" include plural referents unless the content clearly dictates otherwise, and equivalents thereof known to those skilled in the art and so forth.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this disclosure pertains. Although any methods and materials similar or equivalent to those described herein can be used in the practice for testing of the disclosure(s), specific examples of appropriate materials and methods are described herein. The examples set forth above are provided to give those of ordinarily skilled in the art a complete description of how to make and use the embodiments of the compositions or specific constituents, methods of practice, and are not intended to limit the scope of what the inventors regard as their invention. Modifications of the above-described modes for carrying out the invention that is obvious to persons skilled in the art are intended to be within the scope of the following claims. All patents and publications mentioned in the specification are indicative of the levels of skill of those skilled in the art to which the disclosure pertains.
While specific embodiments of the present invention are explicitly disclosed herein, the above specification and examples herein are illustrative and not restrictive. It will be understood that various modifications may be made without departing from the spirit and scope of the invention. Many variations of the disclosure will become apparent to those skilled in the art upon review of this specification and the embodiments below. The full scope of the invention should be determined by reference to the embodiments, along with their full scope of equivalents and the specification, along with such variations. Accordingly, other embodiments are within the scope of the following claims. ,CLAIMS:CLAIMS:
We Claim:
A synergistic herbicidal composition comprising:
bispyribac sodium;
chloracetamide; and
at least one agriculturally acceptable excipient.
The composition as claimed in claim 1, the chloroacetamide herbicide is pretilachlor.
The composition as claimed in preceding claims, wherein herbicidal composition comprising bispyribac sodium and pretilachlor are present in the weight ratio of (1-20): (1-20).
The composition as claimed in claim 1, wherein the herbicidal composition is formulated as granules (GR).
The composition as claimed in preceding claims, wherein the herbicidal composition is used for to control annual grasses, sedges, and broadleaf weeds and in rice, wheat, fruits, roots, tubers, vegetables, maize, grains, sugarcane, cereals, field crops and various other crops for general weed control.
The composition as claimed in preceding claims, wherein the herbicidal composition is applied to pre-emergence, early-post, and post-emergence stages of crops by conventional methods over the target areas.