OA21165A - A method for controlling insect pests in cotton. - Google Patents

Abstract

The present disclosure relates to a method for the control of phytopathogenic insects. More particularly, the present disclosure relates to a method of using insecticides for the control of one or more insects in cotton plant.

Description

TITLE: A METHOD FOR CONTROLLINGINSECT PESTS IN COTTON

Ί

Field of the Invention

The présent disciosure relates to a method for the control of 5 phytopathogenic insects. More particularly, the présent disciosure relates to a method of using insecticides for the control of one or more insects in cotton plants.

Background *

Cotton is one of the most important cash crops in India and is the most 10 widely used fiber throughout the world. The United States of America, Uzbekistan, China, India, Brazil, Pakistan, and Turkey are leading countries in the production of cotton. Different parts of the cotton plant, i.e., fiber, linters, and seeds are useful. Fiber is used to make clothes, cellulose from linters is used in plastics, explosives, and other products, and the seeds provide oil, meal and hulls. Like any other plant, 15 cotton is also susceptible to pest infestation. Aphids, Thrips, Jassids, whiteflies, mealy bugs and bollworms infest cotton crop. I

Bollworms are the moth larvae that attack the fruiting bodies of certain crops including cotton. Diparopsis castanea, Earias perhuegeli, Earias fabia, Earias insulana, Earias vittella, Helicoverpa armigera, Helicoverpa gelotopoeon, 20 Helicoverpa punctigera, Helicoverpa zea, Heliothis virescens, Pectinophora gossypiella, and Pectinophora scutigera are some of the common bollworms. Damage done by Pectinophora gossypiella (pink bollworm) includes rosetted flowers, damaged seed kernels, formation of double seeds, dropping of immature bolls, discoloured lint and burrowed seeds, whereas damage done by Earias vittella 25 (spotted bollworms) includes drying and drooping of terminal shoots before flowering, shedding of squares and young bolls, flared squares, holed and rotten bolls.

Whiteflies are sucking pests that attack certain crops including cotton. They excrete a sticky sugary liquid called honeydew and cause yellowing or death of

leaves. Honeydew attracts ants that interfère with functioning of natural enemies that may control whiteflies and other pests.

Natural enemies of insect pests, also called as biological control agents, are

X the living organisms that are extremely important for reducing the number of pests. 5 Parasitoids such as parasitic wasps, tachinid flies, and rove beetles, pathogens such as Bacillus thuringiensis, and predators such as ladybugs, predatory beetles, predatory mites, and spiders are ail examples of natural enemies.

Fipronil, also known as 5-amino-l-[2,6-dichloro-4(trifluoromethyl)phenyl]-4-[(RS)-(trifluoromethyl)sulfinyl]-lH-pyrazole-3- carbonitrile, is a phenylpyrazole insecticide.

Flonicamid, also known as 5-amino-l-[2,6-dichloro-4(trifluoromethyl)phenyl]-4-[(RS)-(trifluoromethyl)sulfinyl]-lH-pyrazoIe-3carbonitrile, is a pyridine insecticide. A

Ail the aforementioned options for controlling whiteflies and spotted 15 bollworms hâve one or more drawbacks such as less bio-efficacy, high phytotoxicity, and unfavourable effects on natural enemies.

Methods of controlling pests in cotton plants hâve been developed and are in practice. However, methods that show better bio-efficacy along with other benefits such as less or no phytotoxicity, less or no effect on natural enemies, and 20 improved yield and cost benefit ratio are still being sought and are extremely difficult to find.

There is therefore a need in the art for an insecticide that can be used to control one or more of spotted bollworms, pink bollworms, whiteflies, jassids, and thrips, wherein the insecticide shows excellent bio-effïcacy, reduced or no phytotoxicity, reduced or no effect on natural enemies of cotton pests, and which provides improved yield and an improved cost benefit ratio.

Objectives of The Disclosure

The présent disclosure, described hereinafter, achieves at least one of the following objectives.

It is an objective of the présent disclosure to provide a method of controlling 5 insect pests, particularly one or more of spotted bollworms, pink bollworms, whiteflies, jassids and thrips in plants. ¹ ;

It is an objective of the présent disclosure to provide a method of controlling insect pests, particularly one or more of spotted bollworms, pink bollworms, whiteflies, jassids and thrips in cotton plants.

It is an objective of the présent disclosure to provide a method of controlling insect pests, particularly one or more of spotted bollworms, pink bollworms, whiteflies, jassids and thrips in cotton plants that also exhibits a favourable effect on natural enemies of cotton pests such as spiders, chrysopids and coccinellids.

It is an objective of the présent disclosure to provide a method of controlling 15 insect pests, particularly one or more of spotted bollworms, pink bollworms, whiteflies, jassids and thrips in cotton plants that also shows no or less phytotoxic effect.

It is an objective of the présent disclosure to provide a method of controlling insect pests, particularly one or more of spotted bollworms, pink bollworms, 20 whiteflies, jassids and thrips in cotton plants that also results in improved cotton yield.

It is an objective of the présent disclosure to provide a method of controlling insect pests, particularly one or more of spotted bollworms, pink bollworms, whiteflies, jassids and thrips in cotton plants and provides improved cost benefit 25 ratio.

Summary of the Disclosure

In an aspect, the présent disclosure provides a method of controlling pests, particularly one or more of spotted bollworms, pink bollworms, whiteflies, jassids and thrips in plants, said method comprising treating a crop with a combination 5 comprising fipronil and flonicamid.

In an aspect, the présent disclosure provides a method of controlling insect pests, particularly one or more of spotted bollworms, pink bollworms, whiteflies, jassids and thrips in plants, said method comprising treating a cotton crop with a combination comprising fipronil and flonicamid.

In an aspect, the présent disclosure provides a method of controlling insect pests, particularly one or more of spotted bollworms, pink bollworms, whiteflies, jassids and thrips, said method comprising treating a cotton crop with a combination comprising fipronil and flonicamid, wherein fipronil is applied at a dose of 75 g/ha of fipronil.

In an aspect, the présent disclosure provides a method of controlling insect pests, particularly one or more of spotted bollworms, pink bollworms, whiteflies, jassids and thrips, said method comprising treating a cotton crop with a combination comprising fipronil and flonicamid, wherein flonicamid is applied at a dose of 75 g/ha of flonicamid.

In an aspect, the présent disclosure provides a method for controlling insect pests, particularly one or more of spotted bollworms, pink bollworms, whiteflies, jassids and thrips, said method comprising treating a cotton crop with a combination of 75 g/ha of fipronil and 75 g/ha of flonicamid.

In an aspect, the présent disclosure provides a method for controlling insect 25 pests, particularly one or more of spotted bollworms, pink bollworms, whiteflies, jassids and thrips in cotton plants that also exhibits a favourable effect on natural enemies of cotton pests such as spiders, chrysopids and coccinellids, said method comprising treating a crop with a combination comprising fipronil and flonicamid.

In an aspect, the présent disclosure provides a method for controlling insect pests, particularly one or more of spotted bollworms, pink bollworms, whiteflies, jassids and thrips, said method comprising treating a crop with a wettable granular formulation comprising fipronil and flonicamid.

In an aspect, the présent disclosure provides a method for controlling one or more of spotted bollworms, pink bollworms, whiteflies, jassids, and thrips, said method comprising treating a cotton crop with a wettable granular formulation comprising fipronil and flonicamid at the rate of 500 g/ha.

In an aspect, the présent disclosure provides a method for controlling one or 10 more of spotted bollworms, pink bollworms, whiteflies, jassids and thrips, said method comprising treating a cotton crop with a wettable granular formulation * comprising 15 wt% fipronil and 15 wt% flonicamid.

Detailed description of disclosure

As used herein, the term “pest” refers to an organism, and in particular an insect, which is detrimental to the growth, reproduction, and/or viability of a plant, a portion of the plant or a plant seed. In an aspect, the pest is an insect pest such as a spotted bollworm, a pink bollworm, a whitefly, a jassid, and/or a thrip. In an aspect, the plant is a cotton plant.

As used herein, the term control as it relates to a pest, includes the killing of the pest, as well as protecting a plant, a portion of the plant, or a plant seed from attack or invasion by said pest.

It has surprisingly been found by the inventors that the combination of fipronil with flonicamid effectively Controls the whitefly and spotted bollworm 25 population in cotton plants while being economical, and showing reduced phytotoxicity and improved yield. This effective control which is synergistic in nature was not seen when either the fipronil suspension concentrate (SC) or flonicamid wettable granular formulation (WG) were individually used in isolation (on their own), but was observed when the two insecticides were used in

combination in a wettable granular formulation. This synergistic complémentation between the fipronil and flonicamid was unexpected and surprising.

In an embodiment, fipronil and flonicamid are applied as a wettable granular formulation.

In an embodiment, the wettable granular formulation comprises fipronil in an amount of 10 weight percent (wt%) to 20 wt%, or 12 wt% to 18 wt%, or 13 wt% to 17 wt%, or 14 wt% to 16 wt%, based on the total weight of the wettable granular formulation. In an embodiment, the wettable granular formulation comprises flonicamid in an amount of 10 wt% to 20 wt%, or 12 wt% to 18 wt%, or 13 wt% to 10 17 wt%, or 14 wt% to 16 wt%, based on the total weight of the wettable granular formulation. As used herein, the weight percentage is based on the total weight of the wettable granular formulation.

In another embodiment of the disclosure, the wettable granular formulation comprises 15 wt% fipronil and 15 wt% flonicamid, based on the total weight of the 15 wettable granular formulation.

In still another embodiment of the disclosure, the wettable granular formulation comprising fipronil and flonicamid is applied at an application rate in the range of 300 to 1000 grams per hectare (g/ha), or 400 to 600 g/ha, or 400 to 500 g/ha. In an embodiment, the wettable granular formulation is applied to locules of the cotton 20 crop at rate of 500 g/ha.

In still another embodiment of the disclosure, the wettable granular formulation comprises 15 wt% fipronil and 15 wt% flonicamid, based on the total weight ofthe wettable granular formulation, wherein fipronil is applied at a dose of 45 to 100 g/ha, or 60 to 80 g/ha, or 70 to 80 g/ha. In an embodiment the fipronil is 25 applied at a dose of 75 g/ha.

In still another embodiment of the disclosure, the wettable granular formulation comprises 15 wt% fipronil and 15 wt% flonicamid, based on the total weight of the wettable granular formulation, wherein flonicamid is applied at a dose of 45 to 100 g/ha, or 60 to 80 g/ha, or 70 to 80 g/ha. In an embodiment the flonicamid is applied at a dose of 75 g/ha.

In still another embodiment of the disclosure, the wettable granular formulation comprises 15 wt% fipronil and 15 wt% flonicamid, wherein fipronil and flonicamid are both are applied at a dose of 75 g/ha each.

In still another embodiment of the disclosure, the wettable granular formulation comprising 15 wt% fipronil and 15 wt% flonicamid is applied to control spotted bollworm.

In still another embodiment of the disclosure, the wettable granular formulation comprising 15 wt% fipronil and 15 wt% flonicamid is applied to control whiteflies.

In still another embodiment of the disclosure, the wettable granular formulation comprising 15 wt% fipronil and 15 wt% flonicamid is applied to control jassids. ï

In still another embodiment of the disclosure, the wettable granular formulation comprising 15 wt% fipronil and 15 wt% flonicamid is applied to control thrips.

In still another embodiment of the disclosure, the wettable granular formulation comprising 15 wt% fipronil and 15 wt% flonicamid is applied to control pink bollworms.

In still another embodiment of the disclosure, the wettable granular formulation comprising 15 wt% fipronil and 15 wt% flonicamid is applied to control spotted bollworms, pink bollworms, whiteflies, jassids and thrips in cotton plants, and exhibits a favourable effect on natural enemies of cotton pests such as L spiders, chrysopids and coccinellids. I.

In an embodiment, the disclosed wettable granular formulations are synergistic in controlling insect pests as compared to contacting the insect pests

with a wettable granular flonicamid formulation or a suspension concentrate j fipronil formulation.

In an embodiment, the disclosed wettable granular formulations exhibit synergistic control of whitefly and/or spotted bollworm in cotton plants, and non5 synergistic control of jassids or thrips. In an embodiment, the disclosed wettable granular formulations exhibit synergistic control of whitefly and/or spotted bollworm in cotton plants.

“Synergistic control” is présent when the observed efficacy of the wettable granular formulation comprising the combination of finopril and flonicamid is 10 greater than the expected efficacy. The expected efficacy (E) is calculated using the

H following équation also called as Colby’s formula:

E = (X + Y)-XY/100

In the above équation, X is the efficacy of a formulation including only finopril and Y is the efficacy of a formulation including only flonicamid.

In an embodiment, yield of seed cotton (cottonseed) from a cotton crop treated with the disclosed wettable granular formulation is at least 10% greater, preferably 15 % greater, still more preferably 20% greater than yield of seed cotton from an untreated cotton crop.

The pesticidal composition of the présent disclosure can protect cotton 20 plants from damage caused by the pests, for example, harmful arthropods such as harmful insects and harmful mites, which cause damage by feeding and/or sucking to plants.

As will be demonstrated in the examples, the combination of fipronil and flonicamid, greatly improved the whitefly and spotted bollworm control as well as 25 improved the yield of the cotton plants (cotton crop). The combination did not show any phytotoxicity. The method of the présent disclosure also yielded favourable results against natural enemies of the pests. For example, there is no significant

-I différence in the number of natural enemies présent in cotton plants treated with the disclosed wet granular formulations as compared to untreated cotton plants.

The method of the présent disclosure improves the existing disease control to an unexpectedly high degree and surprisingly improves the yield obtained in an 5 economical way.

According to the présent disclosure, a composition for controlling pests having excellent control efficacy for pests and a method effective for controlling pests can be provided.

These and other advantages of the disclosure may become more apparent 10 from the examples set forth herein below. These examples are provided merely as illustrations of the disclosure and are not intended to be construed as a limitation thereof. Y

EX AMPLE S

Experiments were carried out to evaluate the bio-efficacy of combination of fipronil and flonicamid against the spotted bollworms, pink bollworms, whiteflies, jassids and thrips on cotton plant, h

Total four applications of prescribed treatments were made at an average of 15 days interval using a hand operated, high volume Knapsack sprayer. The first 20 three serial applications were done to control sucking pests and the last three sprays were done to control bollworm complex.

Pre- and post- treatment observations on the sucking pest population, i.e. jassids, whiteflies, aphids and thrips, were recorded on 3 leaves selected randomly from the top, middle, and bottom of 5 randomly selected plants in each plot before 25 spray and at 3, 7, and 12 days after spray (DAS). Observations recorded before spray were transformed to square root, however, data presented in percent population réduction were transformed to arcsin for statistical analysis. The spotted bollworm population was counted on 5 randomly selected plants in each plot at 10 days after each spray, while 20 green bolls were picked at 10 days after each spray

ίο from 5 randomly selected plants and dissectedfor recording of the pink bollworm population. Percent green boll and open boll damage, as well as locule damage, f were also recorded. Observations were transformed to arcsin for statistical analysis.

Phytotoxicity symptoms such as leaf injury on tips/surface, necrosis, 5 wilting, epinasty, and hyponasty were recorded at 3, 5, and 7 days after spray.

Observations were also taken to détermine the effect of treatment on the natural enemies of pests in the cotton crop, i.e., predators and parasites. 5 plants per plot were randomly selected and tagged for recording the population of crysopids, coccinellids, and spiders at 3, 7 and 12 days after spray. The results were 10 transformed to square root for statistical analysis.

Seed cotton yield was also recorded at picking time and presented in the form of quintal per hectare. Cost benefit ratio was also calculated for each I treatment. I i

Efficacy of different treatments in controlling the cotton insect pests was 15 analyzed by analysis of variance.

Treatments were designed to compare the performance of single active formulations (5% fipronil SC or flonicamid 50% WG), the commercially marketed product Thiamethoxam 25% WG (3-[(2-chloro-5-thiazolyl)methyl]tetrahydro-5methyl-N-nitro-4H-l,3,5-oxadiazin-4-imine), and the combination of fipronil and I flonicamid (15 wt% fipronil +15 wt% flonicamid, WG).

Below Table 1 provides a summary of the formulation treatments. For the WG formulations, the percentage of active ingrédient is a weight percent based on the total weight of the WG formulation. For the SC formulation, the percentage of 25 active ingrédient is the weight percent based on the total volume of the SC formulation.

Table 1: Formulations

Sr. No.	Treatment 1	Total Dose of active ingrédients (ml or g/ha)	Active ingrédient concentration (ml or g/ha)
1.	15% Fipronil + 15% Flonicamid, WG	300	90
2.	15% Fipronil + 15% Flonicamid, WG	400	120
3.	15% Fipronil + 15% Flonicamid, WG	500	150
4.	Flonicamid 50% WG	150	75
5.	Fipronil 5% SC	1500	75
6.	Thiamethoxam 25% WG	100	25
7.	Untreated Control		M

Evaluation of Bio-efficacy of Fipronil + Flonicamid WG:

Table 2: Bio-efficacy against jassids on cotton plant

Sr. No.	Treatment	Total Dose of actives ml or g/ha	Jassid population (Before spray)	Jassid population Percent Réduction	Mean
3DAS	7DAS	12 DAS
1.	15% Fipronil + 15% Flonicamid, WG	300	29.67	72.84	85.19	64.38	74.14
2.	15% Fipronil + 15% Flonicamid, WG	400	29.00	75.93	92.52	68.99	79.15
3.	15% Fipronil + 15% Flonicamid, WG	500	33.33	76.03	93.23	69.53	79.60
4.	Flonicamid 50% WG	150	30.67	67.69	74.24	61.71	67.88
5.	Fipronil 5% SC	1500	32.00 1	63.63	59.89	55.09	59.54
6.	Thiamethoxam 25% WG	100	31 .67	71.67	68.39	63.74	67.93

	Untreated Control		30.00	0.00	0.00	0.00	0.00
SEM±	^B	NS	(0.75)	(2.10)	(1.03)
CD at 5%	^B	NS	(2.00)	(6.40)	(3.10)

DAS: Days after spray, NS: Non-significant

Conclusion: It is concluded from the above results in Table 2 that the jassids 5 population was found to be uniform in the main field and ranged from between 29.00 to 33.33 jassids per 15 leaves before the application of the insecticide sprays. The jassids population was found to increase and was above économie threshold Level (ETL) throughout the trial period. The data presented in above Table 2 showed that the maximum mean jassids population réductions were 76.03, 93.23 and 69.53 percent, and were recorded for the treatment containing 15% Fipronil + 15% Flonicamid, WG applied at the rate of 500 g/ha at 3^rd, 7^th and 12^th days after each sprays, respectively. The next greatest réduction in jassid population was observed for the treatment of 15% Fipronil + 15% Flonicamid, WG applied at the rate of 400 g/ha with 75.93, 92.52 and 68.99 percent at 3^rd, 7^th and 12^th days after each sprays, respectively. Treatment with the lower dose of 15% Fipronil + 15% Flonicamid, WG at the rate of 300 g/ha, treatment with Thiamethoxam 25% WG at the rate of 100 g/ha, and treatment with Flonicamid 50% WG at the rate of 150 g/ha, were found next ïn order of effectiveness with 72.84, 85.19 and 64.38 per cent, h.

71.67. 68.39 and 63.74 percent, and 67.69, 74.24 and 61.71 percent population 20 réduction after each spray, respectively. Standard treatment with Fipronil 5% SC at the rate of 1500 ml/ha was found to be less effective compared to the other treatments, however, was superior to the untreated control. Ail three doses of 15% -d

Fipronil + 15% Flonicamid, WG were found to be effective compared to the solo formulations.

The effectiveness of ail treatments as measured by percent réduction in the jassid population, was also evaluated according to Colby’s équation. In Colby’s équation given below, E is the expected efficacy of combination of fipronil and ί

flonicamid, X is the observed efficacy of fipronil SC, and Y is the observed efficacy of flonicamid WG. Observed efficacy values (i.e. X and Y) are respective mean values of percent population réduction for fipronil SC and flonicamid WG. If observed efficacy of the combination of fipronil and flonicamid was greater than its expected efficacy, then the combination was determined to be synergistic. If observed efficacy was equal to or less than the expected efficacy, then combination was determined to non-synergistic.

Colby’s équation: E = (X + Y) - XY/100

Therefore, the expected efficacy of 15% Fipronil + 15% Flonicamid WG is calculated as below.

E= 59.54 + 67.88 - (59.54x67.88/100); i.e. ,87.01%

Observed and expected efficacies were then compared for each of the combination formulations.

Table 3: Comparison of observed and expected efficacy of 15% Fipronil + 15% Flonicamid WG against jassids in cotton plants

Sr. No.	1 Treatment	Observed efficacy in percentage	Expected efficacy in percentage	Différence between observed and actual efficacy in percentage
	15% Fipronil + 15% Flonicamid, WG at the rate of 300 ml or g/ha	1 74.14	1 87.01	-12.87
2.	15% Fipronil + 15% Flonicamid WG at the rate of 400 ml or g/ha	79.15	-7.86
3.	15% Fipronil + 15% Flonicamid WG at the rate of 500 ml or g/ha	79.60 ί	-7.41 L

l.

Based on the information in above Table 3, the combination of 15% fipronil and 15% flonicamid, WG was determined to be non-synergistic in the control of the jassids population in cotton plants.

Table 4. Bio-efficacy against whitefly on cotton plant

Sr. No.	l Treatment	Total Dose of active s ml or g/ha	Whitefly population (Before spray)	Whitefly population Percent réduction	Mean
3 DAS	7 DAS	12 DAS
1.	15% Fipronil+15% Flonicamid, WG	300	85.67	70.04	77.68	61.97	69.90
2.	15% Fipronil +15% Flonicamid, WG	400	79.33	73.34	81.10	66.65	73.70
3.	15% Fipronil + 15% Flonicamid, WG	500	83.33	74.64	82.31	67.87	74.94
4.	Flonicamid 50% WG	150	86.00	65.45	69.11	58.16	64.24
5.	Fipronil 5% SC	1500	“ 1* 82.67	20.18	23.01	14.64	19.27
6.	Thiamethoxam 25% WG	100	86.33	71.43	67.88	63.60	67.64
7.	Untreated Control		85.67	0.00	0.00	0.00	0.00
SEM±	»	NS	(0-95)	(1.05)	(1.00)
CD at 5%	M»	NS	(2 .90)	(3.30)	(3-45)	*

Values are mean of three spray and three réplications.

DAS: Days aller spray, NS: Non-significant.

Whitefly population was found uniform in the main fïeld and ranged * between 79.33 to 86.33 whiteflies per 15 leaves before application of the insecticide sprays. Whitefly population was found to increase and was above the économie threshold level (ETL) throughout the trial period. The data presented in above table 5 showed that the maximum mean whitefly population réductions were of 74.64, 82.31 and 67.87 per cent, and were recorded for the treatment containing 15% Fipronil + 15% Flonicamid, WG applied at the rate of 500 g/ha at 3^rd, 7^th and 12^th days after each sprays, respectively. The next greatest réduction in whitefly population was observed for the treatment having 15% Fipronil + 15% Flonicamid, 10 WG at the rate of 400 g/ha with 73.34, 81.10 and 66.65 percent réduction at 3^rd, 7^Λ and 12^th days after each sprays, respectively. Treatment with the lower dose of 15% Fipronil + 15% Flonicamid WG at the rate of 300 g/ha, treatment with Thiamethoxam 25% WG at the rate of 100 g/ha, and treatment with flonicamid 50% WG at the rate of 150 g/ha, were found next in order of effectiveness with 70.04, 15 77.68 and 61.97 percent, 71.43, 67.88 and 63 60 percent, and 65.45, 69.1 and 58.16 per cent population réduction at 3^rd, 7^Λ and 12^th days after each sprays, respectively. Standard treatment with Fipronil 5% SC applied at the rate of 1500 ml/ha was found to be less effective compared to the other treatments, however, was superior to the untreated control. Ail three doses of 15% Fipronil + 15% Flonicamid, WG were 20 found to be effective compared to the solo formulations.

This effectiveness of ail treatments as measured by percent réduction in the whitefly population, was also evaluated according to Colby’s équation as below.

E= 19.27 + 64.24 - (19.27x64.24)/100, i.e. 71.14

Efficacy values are respective values are percent population réduction. 25 Observed and expected efficacies were then compared for combination.

l.

Table 5: Observed and expected efficacy of 15% Fipronil + 15% Flonicamid WG against whitefly in cotton

Sr. No.	Treatment 1	Observed efficacy in percentage	Expected efficacy in percentage	Différence between observed and actual efficacy in percentage
1.	15% Fipronil + 15% Flonicamid WG at the rate of 300 ml or g/ha	69.90	71.14	-1.24
2.	15% Fipronil + 15% Flonicamid WG at the rate of 400 ml or g/ha	73.70	2.56
3.	15% Fipronil + 15% Flonicamid WG at the rate of 500 ml or g/ha	74.94	3.8 1

Based on the information in above Table 5, the combination of 15% fipronil and 15% flonicamid, WG, applied at 400 ml or g/ha or at 500 ml or g/ha, was determined to be synergistic in the control of the whitefly population in cotton plants.

3. Bio-efficacy against Thrips on cotton plant.

Table 6

Sr. No.	Treatment	Dose ml or g/ha	Thrips population (Before spray)	Thrips population Percent réduction	Mean
3DAS	7DAS	12 DAS
1.	15% Fipronil + 15% Flonicamid, WG	300	125.00	74.81	80.20	68.21	74.41
2.	15% Fipronil + 15% Flonicamid, WG	400	125.67	78.92	86.88	73.12	79.64
3.	15% Fipronil + 15% Flonicamid, WG	500	137.67	80.25	87.10	73.83	80.39

4.	Flonicamid 50% WG	150	138.00	37.31	32.44	27.11	80.39
5.	Fipronil 5% SC	1500	135.33	74.78	80.50	70.62	75.30
6.	Thiamethoxam 25% WG	100	133.00	68.71	68.90	67.12	68.24
7.	Untreated Control	«	137.67	0.00	0.00	0.00	0.00
SEM±		NS	(1.22)	(1.85)	(1-15)
CD at 5%	V·	NS	(3 .72)	(5.30)	(3.50)

Values are mean of three spray and three réplications.

DAS: Days after spray, NS: Non-significant * 1

Thrips population was found uniform in the main field and ranged from between 125.00 to 138.00 thrips per 15 leaves before application of the insecticide sprays. Thrips population was found increase and was above économie threshold level (ETL) throughout the trial period. Ali insecticidal treatments significantly reduced the Thrips population effectively, however, the maximum mean Thrips population réductions were 80.25, 87.10, and 73.83 percent, and were recorded for the treatment containing 15% Fipronil + 15% Flonicamid, WG applied at the rate of 500 g/ha at 3^rd, 7^th and 12^Λ days after each sprays, respectively. The next greatest réduction in thrips population was observed for the treatment of 15% Fipronil + 15% Flonicamid, WG at the rate of 400 g/ha with 78.92, 86.88 and 73.12 percent réduction at 3^rd, 7^th and 12^th days after each sprays, respectively. Treatment with the lower dose of 15% Fipronil + 15% Flonicamid, WG applied at the rate of 300 g/ha with 74.81, 80.20 and 68.21 percent réduction, treatment with standard check, Fipronil 5% SC applied at the rate of 1500 ml/ha with 74.78, 80.50 and 70.62 percent réduction, treatment with Thiamethoxam 25% WG at the rate of 100 g/ha with 68.71, 68.90 and 67.12 percent réduction, and treatment with Flonicamid 50% WG at the rate of 150 g/ha resulted in 72.61, 79.96 and 65.53 percent réduction.

i.

and were found to be on par with one another irrespective of the number of sprays and day interval of observations.

This effectiveness of ail treatments was also evaluated according to Colby’s équation as below.

E= 75.30 + 80.39- (75.30*80.39)/100; ï.e., 95.16%

Effïcacy values are respective values are percent population réduction.

Observed and expected effïcacies were then compared for combination.

Table 7: Observed and expected effïcacy of 15% Fipronil + 15% Flonicamid WG against thrips in cotton

Sr. No.	Treatment	Observed effïcacy in percentage	Expected effïcacy in percentage	Différence between observed and actual effïcacy in percentage
1.	15% Fipronil + 15% Flonicamid, WG at the rate of 300 ml or g/ha	74.41	! 95.16 i.	-20.75
2.	15% Fipronil + 15% Flonicamid, WG at the rate of 400 ml or g/ha	79.64	-15.52
3.	15% Fipronil + 15% Flonicamid, WG at the rate of 500 ml or g/ha	80.39	-14.77

Based on the information in above Table 7, the combination of 15% fipronil and 15% flonicamid, WG was determined to be non-synergistic in the control of thrips population in cotton plants.

Table 8: Bio-efficacy against spotted bollworm on cotton plants

Sr. No.	Treatment	Total Dose of actives ml or g/ha	Per cent population Réduction	Mean
10 DASS	10 DATS	10 DAFS
1.	15% Fipronil + 15% Flonicamid, WG	300	66.67	68.44	65.89	67.00
2.	15% Fipronil + 15% Flonicamid, WG	400	70.56	75.07	72.59	72.74
3.	15% Fipronil + 15% Flonicamid, WG	500	74.89 1	77.33	74.07	75.43
4.	Flonicamid 50% WG	150	8.33	10.48	8.59	9.13
5.	Fipronil 5% SC	1500	67:07	72.69	69:67	69.81
6.	Thiamethoxam 25% WG	100	5.00	6.84	4.22	5.35
7.	Untreated Control		0.00	0.00	0.00	0.00
SEM±	M	(1.74)	(1.88)	(1.69)	M
CD at 5%	M	(5.1 0)	(5.65)	(5.08)	M

Values are mean of three spray and three réplications.

DASS: Days after second spray, DATS: Days after third spray, DAFS: Days after first spray, NS: Non-significant

Spotted bollworm {Earias spp.)

The incidence of spotted bollworm was noticed at time of second spray onward during both seasons. The data presented in above Table 8 showed that the

maximum spotted bollworm population réduction was of 72.22, 76.72 and 74.76 percent recorded at 10 days after second, third and fourth sprays, respectively, for the treatment containing 15% Fipronil + 15% Flonicamid, WG at the rate of 500 g/ha. The treatment of 15% Fipronil + 15% Flonicamid, WG at the rate of 500 g/ha 5 was found to be on par with 15% Fipronil + 15% Flonicamid, WG at the rate of 400 g/ha with 70.57, 75.61 and 73.78 per cent réduction al 10 days after second, third and fourth sprays, respectively. Treatment having the lower dose of 15% Fipronil + 15% Flonicamid, WG at the rate of 300 g/ha and the treatment of Fipronil 5% SC at the rate of 1500 ml/ha were found to be at par with one another and recorded the next effective treatments to control spotted bollworm populations. Standard checks, Flonicamid 50% WG at the rate of 150 g/ha and Thiamethoxam 25% WG at the rate of 100 g/ha failed to control spotted bollworm populations. However, they were superior to untreated control.

This effectiveness of ail treatments was also evaluated according to Colby’s 15 équation. In the Colby’s équation given below, E is the expected efficacy of combination of fipronil and flonicamid, X is the observed efficacy of flonicamid SC and Y is the observed efficacy of fipronil WG. If observed efficacy of combination of fipronil and flonicamid was greater than expected efficacy, then combination was determined to be synergistic. If observed efficacy was equal to or 20 less than expected, then combination was determined to non-synergistic. h

Colby’s équation E = X + Y - XY/100

Therefore, expected efficacy of 15% Fipronil + 15% Flonicamid WG is calculated as below.

E= 69.81 +9.13- (69.81 *9.13)/100: i.e., 72.57%

Efficacy values are respective values are percent population réduction.

Table 9: Observed and expected efficacy of 15% Fipronil + 15% Flonicamid WG against spotted bollworm in cotton

Sr. No.

T reatment

Observed efficacy in percentage 1

Expected efficacy in percentage

Différence between observed and

				actual efïïcacy in percentage
1.	15% Fipronil + 15% Flonicamid, WG at the rate of 300 ml or g/ha	67.00	72.57 L h	-5.57
2.	15% Fipronil + 15% Flonicamid, WG at the rate of 400 ml or g/ha	72.74	0.17
3.	15% Fipronil + 15% Flonicamid, WG at the rate of 500 ml or g/ha	75.43	2.86

Based on the information in above Table 9, the combination of 15% fipronil and 15% flonicamid, WG when administered at the rate of 400 or 500 ml or g/ha or was determined to be synergistic in the control of spotted bollworm population in 5 cotton plants.

Table 10: Evaluation of boll and locule damage due to pink boll worms in cotton plants

Sr. No.	T reatment	Total Dose of actives ml or g/ha	Open boll damage (%)	Yield q/ha	CB Ratio
Boll basis	Locule Basis
Boll basis	Locule Basis
1.	15% Fipronil + 15% Flonicamid, WG	300	9.33	4.26	14.60	1:2.19
2.	15% Fipronil + 15% Flonicamid, WG	400	7.33	3.71	15.36	1:2.23
3.	15% Fipronil + 15% Flonicamid, WG	500	6.33	3.08	15.67	1:2.21
4.	Flonicamid 50% WG	150	19.67	9.15	13.71	1:1.97
5.	Fipronil 5% SC	1500	7.00	4.05	14.44	1:1.87

6.	Thiamethoxam 25% WG	100	23.33	μ 11.60	13.42	1:2.14
7.	Untreated Control		24.00	12.97	11.82	1:1.95
SEM±		(1.00)	(0.58)	(0.33)
CD at 5%		(3.20)	(1.75)	(1.05)

Values are mean of three réplications.

Bollworm Damage due to Pink bollworm (Pectinophora gossypiella)

Minimum open bolls and locule damage was recorded in the treatment containing 15% Fipronil + 15% Flonicamid, WG applied at the rate of 500 g/ha with 6.33 and 3.08 percent. The treatment 15% Fipronil + 15% Flonicamid, WG applied at the rate of 500 g/ha was at par with 15% Fipronil + 15% Flonicamid, WG applied at the rate of 400 g/ha with 7.33 open bolls damage and 3.71 percent locule 10 damage.

Standard check. Fipronil 5% SC applied at the rate of 1500 ml/ha was found to be the next effective treatment to reduce open boll and locule damage. Treatment with Flonicamid 50 % WG applied at the rate of 150 g/ha and treatment with Thiamethoxam 25 % WG applied at the rate of 100 were found to be less effective, 15 however, they were superior to the untreated control. Maximum open boll damage and locule damage, i.e., 24.00 and 12.97 percent, were observed in the untreated control, respectively.

Seed cotton yield:

Seed cotton yield was significantly greater in ail the insecticidal treated plots over untreated plots. Highest seed cotton yield was recorded in the plots treated with 15% Fipronil + 15% Flonicamid, WG at the rate of 500 g/ha (i.e. 15.67 q/ha), which was at par with the treatment of 15% Fipronil + 15% Flonicamid, WG at the rate of 400 g/ha (i.e., 15.36 q/ha). The treatment with 15% Fipronil + 15% 25 Flonicamid, WG at the rate of 300 g/ha was the next greatest yield retaining

treatment with 14.60 q/ha. Maximum cost benefit ratio was found in plots treated with 15% Fipronil + 15% Flonicamid, WG applied at the rate of 400 g/ha followed by 15% Fipronil + 15% Flonicamid, WG applied at the rate of 300 g/ha.

Table 11 : Effect of Fipronil + Flonicamid WG on natural enemies in cotton ecosystem

Sr. No.	Treatment	Total Dose of actives ml or g/ha	Spiders/ 5 Plants	Coccinellids/ 5 Plants
BS	3 DAS	7 DAS	12 BS	3 DAS	7 DAS	12 DAS
1.	15% Fipronil + 15% Flonicamid, WG	300	3.33	2.92	3.00	2.00	1.33	1.50	1.67
2.	15% Fipronil + 15% Flonicamid, WG	400	3.67	3.17	3 25	1.33	0.83	1.00	1.10
3.	15% Fipronil + 15% Flonicamid, WG	500	4.33	3.67	3.75	2.33	1.37	1.67	1.83
4.	Flonicamid 50% WG	150	4.67	4.00	4.17	2.67	2.00	2.17	2.33
5.	Fipronil 5% SC	1500	3.00	2.58	2.67	1.00	0.73	0.80	0.87
6.	Thiamethoxam 25% WG	100	4.00	3.33	3.67	2.67	1.50	1.83	2.00
7.	Untreated Control	M	5.00	4.67	5.33	1.67 t	2.00	2.17	2.33
CD at 5%		NS	NS	NS	NS	NS	NS	NS

BS- Before spray. DAS- Days after spray, NS- Non-significant

No long-term adverse effect of any treatments were observed on the natural enemies (spiders, chrysopids, and coccinellids) prevailing in the cotton crop ecosystem. One of the reasons for the decrease in population of natural enemies may be assigned to decrease in pest population after the spraying of treatments. The présent combination was found to be at par with the untreated control irrespective % of days of observations and number of sprays.

It was thus found that the combination of fipronil and flonicamid demonstrated synergistic control of the whitefly and spotted bollworm population in cotton plants. It was further found that said combination demonstrated nonsynergistic control of jassids and thrips. Said combination also resulted in improved yield while being economical. It also yielded favourable results on natural enemies of pests in cotton.

The use of the terms “a” and “an” and “the” and similar referents (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms first, second etc. as used herein are not meant to dénoté any particular ordering, but simply for convenience to dénoté a plurality of, for example, layers. The terms “comprising”, “having”, “including”, and “containing” are to be construed as open-ended terms (i.e., meaning “including, but not limited to”) unless otherwise noted. “About” or “approximately” as used herein is inclusive of the stated value and means within an acceptable range of déviation for the particular value as determined by one of ordinary skill in the art, considering the measurement in question and the error associated with measurement of the particular quantity (i.e., the limitations of the measurement System). For example, “about” can mean within one or more standard déviations, or within ± 10% or 5% of the stated value. Recitation of ranges of values are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the spécification as if it were individually recited herein. The endpoints of ail ranges are included within the range and independently combinable. Ail methods described herein can be performed in a suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and ail examples, or exemplary language (e.g., “such as”), is intended merely to better

I illustrate the invention and does not pose a limitation on the scope of the invention h unless otherwise claimed. No language in the spécification should be construed as indicating any non-claimed element as essential to the practice of the invention as used herein.

While the invention has been described with reference to an exemplary embodiment, it will be understood by those skilled in the art that various changes may be made and équivalents may be substituted for éléments thereof without departing from the scope of the invention. In addition, many modifications may be 5 made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include ail embodiments falling within the scope ofthe appended daims. Any combination of 10 the above-described éléments in ail possible variations thereof is encompassed by the invention unless otherwise indicated herein or otherwise clearly contradicted by context.

Claims (8)

1. A method for controlling whitefly and/or spotted bollworm insect pest in a cotton crop comprising contacting the insect pests with a wettable granular 5 formulation comprising fipronil and flonicamid.

2. The method as claimed in claim 1, wherein the wettable granular formulation is applied to the cotton crop at a rate of 150 g/ha.

3. The method as claimed in claim 1, wherein the wettable granular formulation is synergistic in controlling the insect pests as compared to contacting 10 the insect pests with a wettable granular flonicamid formulation or a suspension concentrate fipronil formulation.

4. The method as claimed in claim 1, wherein fipronil is applied at a dose of 45 to 100 g/ha and flonicamid is applied at a dose of 45 to 100 g/ha.

5. The method as claimed in claim 1, wherein the wettable granular

15 formulation comprises 10-20 wt% flonicamid and 10-20 wt% fipronil, based on the I total weight of the wettable granular formulation.

6. The method as claimed in claim 1, wherein the wettable granular formulation is applied to locules of the cotton crop at rate of 300-1000 g/ha.

7. The method as claimed in claim 1, wherein the contacting comprises 20 a spray treatment, and wherein the spray treatment is repeated within a period of I V from 2 to 8 months from the first spray treatment.

8. The method as claimed in claim 1, wherein the wettable granular formulation exhibits synergistic control of whitefly and/or spotted bollworm, and non-synergistic control of jassids or thrips. i

25 9. The method as claimed in claim 1, wherein the wettable granular formulation exhibits synergistic control of whitefly and/or spotted bollworm in the cotton crop.