Cotton: Pest, Symptoms of damage, Seasonal occurrence, Natural enemies & Pesticides recommended

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Plant protection strategy and activities have significant importance in the overall crop production programmes for sustainable agriculture. Variation of Bt gene expression in different cultivars over time and efficacy to bollworms are the main concern now a days, studies undertaken on Earias spp proved the concerned. Similarly the efficacy of Bt cotton in the field is losing efficacy against the pink bollworm, survey conducted revealed high infestations in green bolls. Monitoring of lepidopterous pest population viz sex pheromone and light traps was carried out and forecast the increasing trend in all bollworms population.

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Studies on red and dusky cotton bugs continued and efforts are made to find bio agents for long term solutions. Seed treatment effect and development of natural on early and normal planting studies revealed that the population of jassid was more on early sown field than normal sowing also the natural fauna was recorded higher in the early sown. The distinct efforts of researchers of the section have proved meaningful in devising pest management strategies against common and new emerging insect pests through application of IPM. Studies are continued on host plant tolerance of CCRI, Multan and National Coordinated Bt. & non-Bt. Strains. The section also studied effect of different IPM strategies on insect pest for transgenic cotton. Screening of new insecticides was also conducted against major insect pests of cotton.

Important pests of cotton:

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Name of pest Scientific Name Family Order
Thrips Thrips tabaci Thripidae Thysanoptera
Jassid Amrascadevastans Jassidae Hemiptera
Whitefly Bemisia tabaci Aleyrodidae Homoptera
Mealybug Phenacoccus solenopsis Psuedococcidae Hemiptera
Red Cotton Bug Dysdercus cingulatus Pyrrhocoridae Hemiptera
Dusky Cotton Bug Oxycarenus hyalipennis Lygaeidae Hemiptera
Mites Tetranychustelarius Tetranychidae Acarina
Pink bollworm Pectinophoragossypiella Gelechiidae Lepidoptera
Spotted Bollworm Eariasvittella Noctuidae Lepidoptera
spiny bollworm Eariasinsulana Noctuidae Lepidoptera
American Bollworm Helicoverpa armigera Noctuidae Lepidoptera
Armyworm Spodopteralitura Noctuidae Lepidoptera

Symptoms of damage:

Name of pest Symptoms of damage
Thrips Leaves of seedlings become wrinkled and distorted with white shiny patches, older crop presents rusty appearance from a distance.
Jassid Affected leaves curl downwards, turn yellowish, then to brownish before drying and shedding, “hopper burn” stunts young plants.
Whitefly Upward curling of leaves, reduced plant vigour, lint contamination with honey dew and associated fungi, transmission of leaf curl virus disease.
Mealybug The extraction of sap by the mealybug results in the leaves of the plant turning yellow and becoming crinkled or malformed, which leads to loss of plant vigour, foliage and fruit-drop, and potential death of the plant.
Red Cotton Bug Feed on developing and mature seeds, stain the lint to typical yellow colour, reddish nymphs seen in aggregations around developing and open bolls.
Dusky Cotton Bug Associated with ripe seeds, all stages characterized by a powerful smell, discolour the lint if crushed.
Mites The first sign of damage is bronzing of the upper leaf surface near the petiole or leaf fold. As numbers increase, the leaves turn red and become covered in fine webbing, and affected leaves may dry and fall off.
Pink bollworm “Rosetted” bloom pink larvae inside developing bolls with interloculi movement .
Spotted Bollworm Bore mark in main shoot, dried and withered away shoot, twining of main stem due to auxillary monopodia, feeding holes in flower buds and bolls blocked by excrement.
spiny bollworm Bore mark in main shoot, dried and withered away shoot, twining of main stem due to auxillary monopodia, feeding holes in flower buds and bolls blocked by excrement.
American Bollworm Small amount of webbing on small squares injured by young larvae, squares have around hole near the base,larval frass and flaring of bracts on larger squares, clean feeding of internal contents of bolls, excessive shedding of buds and bolls.
Armyworm Young larvae in groups skeletinise leaves and older larvae voraciously defoliate leaves .

Seasonal occurrence of cotton pest in Pakistan:

Name of pest Month of attack
Thrips June and July
Jassid July
Whitefly July-September
Mealybug October-November
Red Cotton Bug October-November
Dusky Cotton Bug Though our crop
Pink bollworm August-November
Spotted Bollworm July-September
American Bollworm August-October
Armyworm

List of natural enemies of cotton pest:

Predator/Parasitoid Host Attack Stage
Green lace wings, pirate bugs Lady bird
beetle: Coccinella
septempunctataMenochilus
sexmaculatus, Brumodies sp. , Scymnus
Thrips Nymph and adult
Green lace wings Jassid All stages
Lady bird beetle: Coccinella
septempunctataMenochilus 
sexmaculatus, Brumodies sp. , Scymnus 
Eretnocerus serius
Whitefly Egg and Numph
Lady bird beetle: Coccinella
septempunctataMenochilus 
sexmaculatus, Brumodies sp. , Scymnus , 
aenasius bamby wali.
Mealybug Adult and larvae, adult
Lady bird beetle: Coccinella
septempunctataMenochilus 
sexmaculatus, Brumodies sp. , Scymnus

Shield bug Eucantheconidea furcellata 
Apanteles angaleti 
Elasmus johnstoni
Pink bollworm Larvae
Lady bird beetle: Coccinella 
septempunctataMenochilus 
sexmaculatus, Brumodies sp. , Scymnus
 
Shield bug Eucantheconidea furcellata 
Mirid bug Nesidiocoris tenius
Spider: Oxyopes sp., Clubionia sp., Thomisus sp.
Brachymeria nephantidis
Spotted Bollworm Larvae
Lady bird beetle: Coccinella
septempunctataMenochilus 
sexmaculatus, Brumodies sp. , Scymnus

Shield bug Eucantheconidea furcellata 
Spider: Oxyopes sp., Clubionia sp.,
Thomisus sp.
Trichogramma chilonis
American Bollworm Larvae
Aphidius colemani, Lady bird beetle:
Coccinella septempunctataMenochilus
sexmaculatus, Brumodies sp. , Scymnus
Syrphid fly
Aphid Egg, nymph and adults
Anthocorid bug Orius minutus 
Wasp Eumenes petiolata and Delta sp
Mirid bug Nesidiocoris tenius 
Spider: Oxyopes sp., Clubionia sp.,
Thomisus sp.
Armyworm Larvae

Pesticides recommended for cotton pests control under different situations:

Sr.# Pest situation recommended insecticide Dose / acre (ml/gm)
1 Seed treatment to control sucking insect pests at an early stage. Imidacloprid 70 WS 
Thiamethoxam 70 WS*
10 gm/kg seed 
5 gm/kg seed
2 Thrips reached ETL, during early stage of crop and clear damage symptoms are visible. Chlorfenpyr 360SC
Spinetoram 120SC
Spinosad 240 SC
Imidacloprid 200SL
Acetamiprid 20 SP
Formathion 25 EC
Etofenprox 30 EC 
Or Any other suitable registered insecticide
100
50
50
80
50
500
200
3 Whitefly population reached ETL, during early stage of crop. Diafenthiuron 500 SC
Spirotetramate 240 SC
Acetamiprid 20SP
Imidacloprid 200 SL
Buprofezin 20SC
Pyriproxyfen 10.8EC
Any other suitable registered insecticide
200
125
150
250
600
400
4 Jassid population reached ETL, during early stage of crop. Dinotefuran 20SC
Dimethoate 40EC
Imidacloprid 200 SL
Nitenpyram 10 SL
Etofenprox 30 EC
Thiamethoxam 25 WG Or
Any other suitable registered insecticide
100
350
200
200
200
24
5 Whitefly & Jassid collectively reached ETL during early stage of crop. Dinotefuran 20SC
Dimethoate 40EC
Imidacloprid 200 SL
Nitenpyram 10 SL
Etofenprox 30 EC
Thiamethoxam 25 WG
Mix with IGR
Buprfoezin 20SC
Pyriproxyfen 10.8EC
100
350
200
200
200
24

600
400
6 Pink bollworm reached ETL. Spinosad 240 SC
Spinetoram 120 SC
Spinetoram 250 WG
Gamma Cyhalothrin
Triazophos 40 EC
Bifenthrin 10 EC
Cypermethrin 10 EC
Deltamethrin2.5 EC
Tralomethrin
Fenvalerate 20 EC 
Or
Any other suitable registered insecticide
50
100
40
100
1000
275
333 / 365
300
80
250 / 265

7 Spotted bollworm reached ETL Spinosad 240 SC
Spinetoram 120 SC
Cypermethrin 10 EC
Deltamethrin 2.5 EC
Beta-Cyfluthrin 25 EC
Cyhalothrin 2.5 EC
Fenvalerate 20 EC
Alpha cypermethrin 5 EC
Or
Any other suitable registered insecticide
40
40
300 / 325
333 / 365
250 / 275
333 / 370
400 / 450
440 / 490


8 American bollworm reached ETL at early stage. Spinosad 240 SC
Spinetoram 250 WG
Chlorfenapyr 360 SC
Emamectin Benzoate 1.9 EC
Chlorpyrifos 40 EC
Profenofos 500 EC
Indoxacarb 150 SC
Thiodicarb 80 DF
Or
Any other suitable registered insecticide
100
60
333
200
1000
1000
175
480

9 Aphids reached ETL in later part of the crop life. Carbosulfan20 EC
Diafenthiuron 500 SC
Chlorpyrifos 40 EC
Quinalphos 25 EC 
Or
Any other suitable registered insecticide
500
200
750
1250

10 Mites reached ETL. Spiromesifen 240 SC
Fenpyroxymate 5 SC
Azocyclotin 25 WP
Pyridaben 15 EC
Amitraz 20 EC
Diafenthiuron 500 SC
Ethion 46 EC
Triazophos 40 EC
Chlorfenapyr360 EC
Hexythiazox 10 WP 
Or
Any other suitable registered insecticide
100
200
150
500
1000
200
1000
600
333
220

11 Armyworm attack on cotton.** Methoxyfenozide 240 SC
Lufenuron 50 EC*
Flubendamide 480 SC
Emamectin Benzoate 1.9 EC
Tebufenazide 20
Acephate 75 SP
Indoxacarb 150 SC
Methomyl 42 SP***
Or
Any other suitable registered insecticide
200
200
50
250
350
750
175
500

12 Black headed cricket. Bait
Ingredients:
1. Rice husk (Bhossi) 10 kg/acre
2. Methamidophos½ litre
3. Gur (Molasses) 1 kg
4. Water As per requirement
The formulated material is for one acre.
13 Mealy bug infestation during early stage of crop. Acetamiprid 20 SP
Imidacloprid 200SL
150
250
14 Mealy bug infestation during late stage of crop. Profenofos 50 EC
Methidathion 40 EC
Chlorpyrifos 40 EC
800
400
1000
15 Dusky cotton bug. Fipronil
Clothianidin
Triazophos
Imidacloprid + Fipronil
480
150
660
60
16 Red cotton bug. Fipronil 5 SC
Triazophos 40 EC
Cypermethrin + Chlorpyrifos
Triazophos + Deltamethrin
Imidacloprid + Fipronil
480
660
500
600
60

Notes:Doses of the chemicals are based on the concentration given in the above table. If different formulation than given is used, dose may be adjusted accordingly.

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