insects pests of cotton and their ipm methods

1. Topic: Insects pests of
cotton and their IPM
Presented By:
Ammad Ahmad
Department of
Entomology
UCA&ES
The Islamia
University of Bahawalpur

2. Cotton importance
 Pakistan is 5th largest producer of cotton
 3rd largest exporter of cotton
 Cotton has the major share of 7 per cent in the
GDP of Pakistan
 Cotton production supports Pakistan’s largest
industrial sector, comprising 400 textile mills
 It is cultivated primarily for lint
 Raw cotton is also used for medical and surgical
purposes
 Seed is crushed for edible oil

3. Insects Pests of cotton
Pest ETL Damage symptoms
1. Aphid (Aphis gossypi) 15/ leaf Leaf crumpling and downward
curling of leaves, sticky cotton
due to deposits of honey dew
on open bolls.
2. Thrips (Thrips tabaci) 8-10 insects/leaf Leaves of seedlings become
wrinkled and distorted with
white shiny patches, older
crop presents rusty
appearance from a distance.
3. White fly (Bimisia tabaci) Adults/nymph or both 5/leaf Upward curling of leaves,
reduced plant vigour, lint
contamination with honey dew
and associated fungi,
transmission of leaf curl virus
disease
4. Jassid (Amrasca devastans) 2 adult or nymph per leaf Affected leaves curl
downwards, turn yellowish,
then to brownish before drying
and shedding, “hopper burn”
stunts young plants

4. Pest ETL Damage Symptoms
5. Mealy bug (Phenococus
solenopsis)
On appearance 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.
6. Red cotton bug ( Dysdercus
singulatus)
Feed on developing and
mature seeds, stain the lint to
typical yellow colour, reddish
nymphs seen in aggregations
around developing and open
bolls.
7. Dusky cotton bug (Oxycarenus
hyalipennis)
Associated with ripe seeds, all
stages characterized by a powerful smell,
discolour the lint if crushed.
8. American bollworm (Helicoverpa
armigera)
5 Brown eggs or 3 small larvae or
Both 5 / 25 plants
Small amount of webbing on small squares
injured by young larvae, squares have a
round 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.

5. Pest ETL Damage Symptoms
9. Pink bollworm (Pectinophora
gossypiella)
5 Larvae/ 100 Bolls “Rosetted” bloom pink larvae
inside developing bolls with
interloculi movement
10. Spotted bollworm (Earias
vittella)
3 Larvae/ 25 plants Boremark 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.
11. Army worm (Spodoptera
litura)
On appearance Young larvae in groups
skeletinise leaves and older
larvae voraciously defoliate
leaves

6. Pests Scouting methods
In cotton crop there are two types of insect pests viz. sucking insects and
the chewing insect-pests.
 For the sucking insects 20 leaves of 20 different plants, one from each
from upper, middle and lower portions is selected for observing pest
insect activity randomly.
 For bollworms or chewing insect pests, 25 plants, 5 plants contiguous
at each place randomly are selected and observed for insect pest
activity.
Pest scouting: Pest survey is to asses pest population and
their losses over large area i.e. District, province or country.
Pest scouting is to determine no. of insect pests and their crop
loss in a specific crop field.

7. Integrated pest management
Integrated Pest Management (IPM) is a sustainable
approach to managing pests by combining
biological, cultural, physical and chemical tools in a
way that minimizes economic, health and
environmental risks.

8. Control methods
Cultural control:
 Timely removal and destruction of cotton stubbles
 Deep ploughing to expose the carry-over population of bollworms
 Crop rotation with cereals or pulses
 Growing some resistant varieties i.e. Short duration varieties
 Adopt proper spacing, irrigation and fertilizer management . Avoid
application of high nitrogenous fertilizer

9. Mechanical control:
 Using Yellow sticky traps @ 7-10 traps / ha to monitoring the pest
population ( sucking pests ).
 Hand picking and destruction of various insect stages, affected plant
parts and rosetted flowers.
 Removal of weed hosts – Abutilon indicum and other Malvaceous weed
hosts, Sida sp. Grown in cultivated area.
 Setting of light traps – for monitoing pest population.
 Setting of pheromone trap @ 7-10 traps / ha.

10. Biological control:
BIOLOGICAL CONTROL AGENTS
 PARASITOIDS: Parasitoids are usually equal or smaller in size than the
prey. They live in or on the prey, derive their nutrition from the prey
and usually complete one stage of the life in or on the prey and kill the
prey in the process
 PREDATORS : Predators are organism usually larger and stronger than
prey. They catch and kill a large number of other organisms for food.
 PATHOGENS: Disease causing organisms like
 Bacteria
 Virus
 Fungi
 Protozoa: Nosema, Vairimorpha
 Nematodes: Steinernema , Rhabditis

11. TECHNIQUE OF BIOLOGICAL CONTROL
 Conservation : Conservation is defined the actions to preserve and
increase the natural enemies by environmental manipulation
 Augmentation : It is a tactic of biological control where, the efforts is
made to increase the natural enemy population either by propagation
and release or by environmental manipulation . It includes all the
activities designed to increase the number or effect of existing natural
enemies
 - Inoculation or periodic release
 - Inundative release
 Introduction/Importation : Importing foreign natural enemies to
combat the introduced pests

12. Major parasitoids in Cotton Ecosystem

13. Major predators in cotton ecosystem

14. Chemical control
Pest Insecticide Dose /ha
Jassids, Aphids, Thrips Methyl demeton 25EC
Dimethoate 30EC
Phosphamidon 100EC
500-750 ml
500-750 ml
100-250 ml
Whiteflies Methyl demeton 25EC
Phosalone 35EC
500-750 ml
2.5-3.0 litres
Spotted, Pink and
American bollworms
Endosulfan 35EC
Chlorpyriphos 20EC
Quinalphos 25EC
Monocrotophos 40EC
Carbaryl 50WP
Fenvalerate 20EC
Cypermethrin 10EC
Decamethrin 2.8EC
1.5-2.0 litre
1.5-2.0 litre
1.5-2.5 kg
400-500 ml
800-1000 ml
600-700 ml
Army worm Chlorpyriphos 20EC
Fenvalerate 20EC
Cypermethrin 10EC
Decamethrin 2.8EC
1.5-2.0 litres
400-500 ml
800-1000 ml
600-700 ml

15. Thank you