1. Identification of Insect pests
of sorghum and their symptoms
of damage
Dr. M. Thippaiah
professor
Dept. of Entomology
College of Agriculture
GKVK, UAS
Bangalore- 65

2. Sorghum is a major crop in Maharastra, TN, AP, UP, Rajasthan,
Haryana, Gujarat, Karnataka
In Karnataka – Major crop in Northern Karnataka i.e. Dharwad ,
Bijapur , Raichur, Bellary
and in South grown in Chitradurga, Mysore ,Shivmoga
More than 150 species of Insects have been reported to damage
Sorghum. However, over a dozen species are very serious and
constitute a major constraint in sorghum production
These insect pests are classified as
Borer pests
Ear head feeders
Sap feeders
Defoliators
Non insect pests

3. Borer pests of Sorghum

4. Sorghum shoot fly: Atherigona soccata
(Muscidae : Diptera)
Adult fly
Maggot
inside the
shoot
Fully grown maggot
Adults resembles house fly, little smaller and grayish brown in
colour with 6 black spots on the abdomen
Eggs: are laid on 2 to 5 youngest leaves of sorghum seedlings
Among this it prefers the basal half portion of ventral
surface of leaves I.P: 1 to 2 days
Larvae : there are 4 larval instars
Maggots are apodous and yellowish in colour and tapering to wards
anteriorly
L.P : 6 to 12 days
Pupa : pupation at base of the stem. PP – 6 to 8 days
Life stages of the pest
It is a major pest in all traditional sorghum growing areas like
Maharashtra, TN, and Karnataka
Alternate hosts – Maize, Ragi, Wheat, Bajra
More incidence observed in late kharif and early rabi crop
While Insects cause 12 % loss in Sorghum Production
Shoot fly alone is responsible for 5 %

5. 6 black spots on the abdomen

6. Nature and symptoms of damage
 Maggots on hatching crawls on upper surface of the leaf and later, penetrate /
enter between leaf sheath and stem and further maggot reaches ground
level and feed on growing point between leaf sheath and leaf whorl as a result
in wilting and drying of central shoot know as ‘dead heart ‘ symptoms.
 Growing point soft, succulent protected by leaf sheath and starts decaying
which is fed by maggots, the central shoot dies and more tillers will come out the
maggots will affect these side shoots and when dead hearts are pulled out they
come up easily and produce bad smell
Dead heart ‘ symptom
Incidence - The 1-6 weeks old seedlings are more
susceptible
In Karnataka – June – Sept. incidence will be more
The pest will complete its life cycle quickly at conditions like
 Temp – 25-300 c
 RH - more than 60%
 Continuous rain fall decrease pest incidence

7. Sorghum stem borer: Chilo partellus
( pyralidae : Lepidoptera)
 Adult is a medium sized, straw coloured moth or light brown coloured
moth, 2cm across the wing
 Fore wings are light brownish / yellowish with row of black dots
on the apical margin or outer margin
 Hind wings are whitish in colour in females and straw coloured in males

8. Eggs are laid
in clusters on
the ventral
surface of the
leaves near
the mid rib
Each females
lays – 225 eggs
I.P- 2-5 days
Larva passes 5-6 instars, the larva
yellowish brown with reddish brown head
and prothoracic shield and measures
25mmlong with series of black dots
L.P-28-35 days
It pupate
inside the
stem in a
small
chamber
P.P- 8-15 days
TLC- 30-40
days

9. Nature and symptoms of damage
Larva is damaging stage
 The larvae bores into mid rib
and the shoot and feeds on
the internal tissues and causes
typical ‘dead heart’ formation,
thus killing young plants
 In the early stage – hatching larvae feed
on the surface of leaf sheath and leaf
whorls causing pin holes / shot holes on
the whorls of newly opened leaves
 As the severity of leaf damage increases ,
blend of feeding punctures and scratches
appears on leaves
 The infestation starts 20 days
after seedling emergence and
continued till maturity

11.  After the inter node elongation the growing point moved up wards , the
larvae make tunnel in to the stem and also presence of red patches on the
inter nodal region
 Later infestation occurs on the top portion of the stem
Both stem and peduncle are damaged by the larva leads to production of
complete chaffy ear head or partial chaffy ear heads
The infested peduncle may also break down
Bored hole on
the stem
Presence of red patches
on the inter nodal region

12. Larvae in side the stem
Symptoms
Mid rib tunneling by early instar larva
A series of pin holes on emerging leaves
In young plants the pest causes a typical dead hearts
In older plants the upper part of the stem usually dies due to
boring of the caterpillars in the stem pith

13. Ear head feeders

14. Jowar ear head bug : Calocoris angustatus
(Miridae : Hemiptera)
 It is a key pest of Sorghum in Southern states
 It attack the crop from ear head emergence to
head dough stage,
Yield loss- 54-89%
 Adult is an active, slender yellowish
green bug, measuring 5-8mm in length
 The bugs hover over the ear heads at
the time of ear head formation
Site of ovipositon: Eggs are laid in spikelet's on ear head
or under glumes or middle of the florets
Each female lays - 100-200 eggs I.P – 5-7 days
Nymphs: The nymphs pass 5 instars
Early instars light orange coloured and
later changes to green colour or yellowish
green in colour N.P – 15- 17 days, Two generations are noticed
It inflict severe damage to irrigated Sorghum
during April – May and to less extent to rainfed
Sorghum during Aug - Jan

15. Older grain shows distinct feeding punctures
that reduce grain quality
Both nymphs and adults suck the milky juice from tender ear heads or
developing grains, such grains shrink and turn black colour, thus make
them turn chaffy or crinkled grains.
Older grain shows distinct feeding punctures that reduce grain quality
This bug has been recorded feeding on a number of Cereals, Millets and
grasses, buts breeding is mainly restricted to sorghum
Symptoms of damage

16. Sorghum ear head midge : Contarinia sorghicola
(Cecidomyiidae : Diptera)
Site of ovipostion:
Eggs are laid in side the glumes of
closed and open flowers
Each female lays – 30 – 100 eggs
I.P – 1-2 days
Maggots: are minute, pink, fleshy apodous
L.P – 9-10 days
Pupa : In side the damaged flowers or pupal
cases are usually present at the tip
of the glumes
P.P – 5-6 days
Adults are fragile soft bodied
reddish mosquito like fly with
long legs and monili form antennae
and a pair of transparent wings and they have
long Telescopic ovipositor
Long telescopic
ovipositor

17. Nature and Symptoms of damage
 Maggots on hatching feed on developing grains such infested ear
heads become chaffy i.e.
 The larvae starts feeding on the ovaries and destroy developing grains
results chaffy ear heads or partial filling of grains
partial filling
of grains
chaffy ear heads
 The affected spikelet's shrivel and
fail to develop in to grains
Symptoms
Red ooze from the spikelet when squeezed indicating the presence of Maggots
Chaffy grains with round holes indicating fly emergence
Empty pupal cases protruding from glumes

18.  They have whitish pupal cases protruding out of the of the damaged spikelets
July sown crop – Severely affected
Temp. - 25 – 300 C
RH – 60% these factors encourage the pest population and also
cloudy weather and intermittent rain fall increases the incidence

19. Ear head caterpillar: Helicoverpa armigera
(Noctuidae :Lepidoptera)
 The adult is a medium sized, light brown coloured moth
 Two prominent black spots on the fore wings
 Dull black border on the hind wings
When crop is at flowering stage we can find the adult moth activity

20. Symptoms of damage
Larva remains concealed in the inner branches of the ear and
feed on the grains and damaged ears could be easily spotted
in the field by their chalky appearance due to partially
eaten grains
chaffy ear heads
Female moth lay eggs on inflorensce, the hatching
caterpillar starts feeding on flowers till grain hardening stage

21. Caterpillar feed on the developing grains

22. Grass hopper feeds on the grains

23. Castor shoot and capsule borer: Conogethes punctiferalis
( Pyralidae : Lepidoptera)
Adult is a medium sized moth with
small black dots on pale yellow
wings

24. It attacks the plant at flowering stage and lays eggs on
inflorensce and young caterpillar make webbings and
feed on flowers and grains and they pupate with in
the webbings

25. Chafer beetle : Oxycetonia spp.
(Scarabaeidae : Coleoptera)
A light brown coloured beetle with white spots on the elytra
Adults feeds on ear heads of sorghum and maize

26. Sap feeders

27. Shoot bug : Peregrinus maidis
(Delphacidae : Hemiptera)
Adults are small, active ,light brown or dark brown in colour
with transparent wings and movable spur on the hind legs
The brachypterous female is yellowish while macropterous female
is yellowish brown and male dark brown in colour

28. Eggs are laid in groups
of 1-4 inside the leaf
tissue on midrib and
covered with white
Waxy substance
Maximum 97 eggs are
laid by a female in life
span of 7-10 daysThere are
5 nymphal
instars
4-10 days16-18 days
7-10 days
TLC – 18-31 days

29. Damage
 Both nymphs and adults suck the sap from young leaves and leaf sheath resulting
attacked plants become unhealthy, stunted growth and yellow patches
 The leaves wither from top down wards and later turn reddish and finally
attacked plants die in severe case.
 honey dew secreted by the bug causes growth of sooty mould on the leaves
 Vectors of viral diseases : 1. Sorghum stripe
2. Sorghum mosaic
Nymphs and Adults Attack plants reddish and finally
such plants die in severe case

30. Aphids: Rhopalosiphum maidis
( Aphididae : Hemiptera )
Adults are dark bluish green and some what
ovate .
It is 2mm long with black colored legs with
cornicles on dorsal side of 5th and 6th
abdominal segments
Winged and wingless forms are common
Corn leaf aphid Aphid damage Sugarcane aphid
cornicle

31. Nature of damage
 Nymphs and adults suck the sap from the leaves as a results
yellowing of leaves, colonies of aphids in central leaf whorl,
stem or panicles
 The aphids produces an abundance of honey dew on which
sooty moulds are grown
 In panicles, honey dew may hinder harvesting
 Presence of ants is the indication of attacked by aphids
 The aphids also transmits Maize dwarf mosaic virus

32. Stink bug : Nezara viridula
( Pentatomidae : Hemiptera )
Adults are large
green coloured
bug with 5 segmented
filiform antennae
Nymphs and adults suck the sap from the softer part
of the plant but principally from the developing seeds
The Injury is very negligible
Adults congregate on
The bajra ear head
Nymph is brownish red or dark
brown with multicoloured spots

33. Defoliators

34. Colemania spheneroides (I. Bolivar) on sorghum
It is endemic / cyclic pest in Northern Karnataka
i.e in Haveri district and it appears once in 5 years
Deccan wingless grass hopper : Colemania sphenarioides
( Pyrgomorphidae : Orthoptra )

35. Adult is a medium sized,
wingless grass hopper,
measures 4-5 cm in length
Antennae short filiform
Body light green with pink and
yellow stripes on lateral sides
Eggs : are laid in batches in the forms
egg pod at 5 cm depth in soil in the
month of Octo - Nov. and hatch
in June - July

36. Symptom of damage
After monsoon showers the nymphs will come out and
first feed on grasses and later take over to sorghum
They feed on leaves and also feed on flowers, ripening
ear heads and all parts are eaten leaving only stalk

37. Army worm : Mythimna separata
(Noctuidae : Lepidoptera)
It is serious in heavy rainfall areas
 The adult is stout bodied, medium sized moth, greyish brown in colour
 On the fore wings we find 2 white spots and prominent veins in the wings

38. Caterpillars
Pupae
Pale Brown coloured moth
Caterpillar feeds on leaf margin and mid rib and
thus causing severe defoliation

39. Red headed hairy caterpillar: Amsacta alibistriga
( Arctiidae : Lepidoptera )
Caterpillars are
reddish-brown
in colour and hairy
Adults are medium sized moths
Fore wings : are white with brown streak all
over the wings and yellowish
streak along the anterior margin
Hind wings : are white with black spots
Caterpillars are the voracious feeders of the foliage
They move from field to field in large swarms in search of suitable
host plants thus causing large scale devastation of millet crops

40. Red hairy caterpillar
It is a polyphagous pest, often do considerable injury
to young sorghum seedlings and caterpillars are the
voracious feeders of the foliage

41. Sorghum leaf roller :Marasmia trapezalis
( Pyralidae : Lepidoptera)
Adult is a small, pale yellow brown coloured moth with black
wavy markings on the wings
Site of ovipostion : Eggs are laid singly on the upper leaf surface
I.P – 4-5 days

42. Larva : there are 5 larval instars, pale brown with reddish brown head
and brown prothorax
L.P – 15-20 days
Pupa : Pupation takes place with in leaf fold, P.P – 7-8 days
Symptoms of damage
 The larva folds or roll the leaves and feeds on the green matter
 Longitudinal patches on leaves with drying tips
 Broad leaf varieties are more susceptible for this pest

43. Jowar flea beetle : 1. Chaetocnema sp.
(Chrysomelidae : Coleoptera )
Black shinning beetle and very active, jump when slightly touched
with enlarged hind femora
It is often serious in seedlings of summer and rabi sown crop
Adults feeds on leaves and pin holes observed on leaves

44. 2. Monolepta signata
( Chrysomelidae : Coleoptera )
Adult is a black coloured beetle with
long antennae and four pale yellow
spots on the elytra

45. Adults feeds on the leaves make
holes on the leaves

46. Non insect pest

47. Jowar mite : Oligonychus indicus
( Tetranychidae : Acarina)
Both nymphs and adults suck the sap from the leaves as a results
infested areas become pale yellow but later turn to reddening
of tissues on dorsal side which coalesce and entire leaf red in
colour and dry up
The plant growth and grain development is affected
Webbing can be seen on the undersurface of the leaf
These are microscopic, greenish yellow oval shaped
mites and they found on ventral surface in colonies,
they forms webs
Nymphs are pale yellow in colour