Major pests of Cotton crop and Resistance strategy against them

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Resistance Strategies against
Sucking Insect pests of Cotton
Muhammad Daniyal Junaid
2011-Ag-3758
Supervisor : Dr. Tariq Manzoor Khan

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Resistance Strategies against
Sucking Insect pests of Cotton

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Introduction:
Genus Gossypium
Common name Kapas
Family Malvaceae
Chromosome number (2n) 26, 52
Cultivated species 4
Wild species 46
Diploid (2n=26)
Gossypium herbaceum
Gossypium arboreum
Tetraploid (2n=52)
Gossypium hirsutum
Gossypium barbadense

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Spider Mites
PESTS OF COTTON

5. Sucking Pests
Whitefly
Bemisia tabaci
Symptom of damage:
Chlorotic spots on the leaves which
later coalesce forming irregular
yellowing of leaf tissue which extends
from veins to the outer edges of the
leaves.
Severe infestation results in
premature defoliation
Development of sooty mould
Shedding of buds and bolls and
poor boll opening
Also transmits leaf curl virus
diseases of cotton. ( Schoonhoven et al.,
2005)

6. Dusky cotton bug
Oxycarenus hyalinipennis
Nature of damage:
Adults and nymphs feed on the
sap of immature and partially
matured seeds gregariously and
impart a yellow tinge to the lint.
Symptom of damage:
• Sucks the sap from developing seeds in open bolls and stains
the lint black.
• Seeds discolored and shrunken. (Schoonhoven et al., 2005)

7. Mealy bugs
Phenacoccus sp., Ferrisa sp. and
Maconellicoccus sp.
Nature of Damage:
It feeds on the sap of the plant and
releases toxic substances causing
injury, curling and drying of leaves
which damages fruiting and
drastically decrease the yield.
Mealy bug also attacks the roots
just below the level of the soil,
especially where the root and the
stem meet.

8. Symptom of damage:
Heavy clustering of mealy bugs usually seen under surface of
leaves as a thick mat with waxy secretion.
Excrete honey dew on which the fungus sooty mould grow.
Affected plants appear sick and black, resulting reduced
fruiting capacity.
White fluffy mass on buds, stems, fruit and roots.
Presence of honeydew, black sooty mold, and ants.
Unopened flowers which often shrivel and die.
Small deformed fruits.

9. Nature of Damage:
Cotton Jassids starts infesting the
crop when it is about one and half
month old. The peak infestation is
reached in July and August.
Continuous light rains are most
favorable to increase jassids
population and its infestations.
( Patel, 2014)
JASSID or Leaf hopper (Amrasca (biguttula)
devastans)

10. Symptoms of damage:
• Tender leaves become yellow.
• The margin of the leaves start
curling downwards and reddening
sets in.
• “Hopper burn”
• The margin of the leaves get
broken and crumble into pieces
when crushed.
• The leaves dried up and are shed
and the growth of the crop is
retarded. (Patel, 2014)
Cont…

11. Nature of damage:
• Both nymphs and adults lacerate the
underside of leaf tissues and imbibe the
oozing sap.
• These lacerate the epidermal cells and suck
the sap.
(Whalen et al.,2015)
THRIPS (Thrips tabaci)

12. Damage symptoms:
• Leaf curl up.
• Silvery undersurface of
leaves
• Leaves loose the natural
luster
• Leaf loses its succulence
and at the lower surface,
bronzing is seen.
• Leaves appear sickly and
may show uneven surface.
( Whalen et al., 2015)

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Cotton leafworm/Tobacco caterpillar
(Spodoptera litura):
Polyphagous and is
occasionally a serious pest of
cotton.
Eggs are covered with scales
and hairs. The young larvae
are gregarious and are
solitary in nature. Black and
green body color.

14. Breeding strategies and Important
characters:
 Wide Hybridization
Nectariless cottons
Hairiness
B.t cotton
Gossypol glands
Low greeniness
Hard boll rind
Earliness

15. Control via Breeding techniques
Synthetic Allotetraploid (A1A1G2G2)
between Gossypium herbaceum and G.
australe
(2n = 2x = 26, A1A1)
excellent drought tolerance and resistance to sucking
insects and leaf curl virus.
(2n = 2x = 26, G2G2)
economically valuable characteristics i.e delayed
pigment gland morphogenesis and resistance to
insects, wilt diseases and abiotic
Stress (Liu et al., 2015)
Bridging

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Chrysopa and Chrysoperla.
Coccinellids.
Syrphid.
Spiders.
Geocoris.
Canthocorid sp.
Natural enemies of cotton pests
Biological Control of Pests

17. Natural enemies of pests
 Chrysopa and
Chrysoperla
 Coccinellids

18. Enemies of pests
 Geocoris  Canthocorid sp.

19. 1. Bottrell, D.G. and P.L. Adkisson. 1977. Cotton insect pest
management. Annual Review of Entomology. 22:451-481.
2. Liu, Q., Y. Chen, Y. Wang, J. Chen, T. Zhang and B. Zhou. 2015. A New
Synthetic Allotetraploid (A 1 A 1 G 2 G 2) between Gossypium
herbaceum and G. australe: Bridging for Simultaneously Transferring
Favorable Genes from These Two Diploid Species into Upland Cotton.
PloS one. 10:e0123209.
3. Maxwell-Lefroy, H. 1906. The Insect Pests of Cotton in India, Thacker,
Spink & Company.
4. Patel, Y. 2014. Reaction of Cotton genotypes to Amrasca devastans
(Distant) vis-a-vis crop age. Annals of Plant Protection Sciences. 22:49-
51.
5. Schoonhoven, L.M., J.J. Van Loon and M. Dicke 2005. Insect-plant
biology, Oxford University Press on Demand.
6. Whalen, R., D. Herbert and S. Malone. 2015. Evaluation of Selected
Seed, In-Furrow Liquid At-Planting, and Foliar Insecticides for Control
of Thrips in Cotton, 2014. Arthropod Management Tests. 40:F47.
References: