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:
| 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.
