Castor (Ricinus communis) is a valuable crop primarily grown for its oil-rich seeds, which are used in a variety of applications including lubricants, soaps, pharmaceuticals, and biodiesel. However, like all crops, castor plants can be susceptible to a range of pests that can affect their growth and productivity. Here are some common pests that affect castor plants: Castor Semilooper (Achaea janata) - This caterpillar is one of the most significant and widespread pests of castor. The larvae feed on the leaves of the plants, leading to severe defoliation if not controlled. Capsule Borer (Conogethes punctiferalis) - Also known as the castor shoot and capsule borer, this pest attacks the capsules of the castor plant, damaging the seeds inside. This can significantly reduce the yield and quality of the seeds. Spiny Castor Bug (Eurygaster integriceps) - This bug can cause significant damage by sucking the sap from the leaves, stems, and capsules of the castor plant. Their feeding can also lead to the development of sooty mold on the plants. Whitefly (Bemisia tabaci) - Whiteflies can cause damage by sucking the sap from the leaves and by transmitting various plant viruses. They excrete honeydew, which promotes the growth of sooty mold fungi, further harming the plant. Aphids - These small sap-sucking insects can attack castor plants, leading to leaf curling, stunted growth, and the secretion of honeydew, which encourages sooty mold growth. Mealybugs - Like aphids, mealybugs suck sap from the plants and excrete honeydew. They can cause yellowing of leaves and stunted plant growth. Red Spider Mite (Tetranychus urticae) - This mite can cause damage by piercing plant cells and sucking out their contents, leading to discolored leaves and reduced plant vigor. Management of these pests typically involves an integrated approach that includes cultural practices, biological control, and the judicious use of chemical pesticides. Cultural practices such as crop rotation, maintaining field hygiene, and removing infested plant parts can help reduce pest populations. Biological control involves introducing natural enemies of these pests, such as parasitoids and predators, to help keep their numbers in check. Chemical control should be used as a last resort and should be applied in a manner that minimizes environmental impact and promotes sustainability.

1. Pests of castor
By
Dr. U. Pirithiraj, P.hD.
Assistant Professor (Entomology)
JSACAT
Affiliated to Tamil Nadu Agricultural University

2. Borers

3. Shoot and capsule borer, Conogethes (=Dichocrocis)
punctiferalis, Crambidae (Pyraustidae), Lepidoptera
1
Dr. U. Pirithiraj, P.hD. (Entomology)
Nature of damage
Larvae feed on petiole and young leaves.
Also bore into capsule and peduncle
Symptom of damage
Capsules with bore holes, webbed together.
Peduncle and capsules show galleries made
of silk and frass
It is found from India and Pakistan through south-east
Asia to Australia

4. Eggs are laid on tender parts of plants
Pale greenish with
pinkish tinge, black
blotches and fine hairs
with dark head and
prothoracic shield
Pupation takes place in
cocoons of silk, inside the
stem or capsule
Yellowish with black spots on both pair of wings
Dr. U. Pirithiraj, P.hD. (Entomology)

5. Leaf feeders

6. Castor semilooper, Achaea janata, Dysgonia algira
(Parallelia algira), Noctuidae, Lepidoptera
2
Dr. U. Pirithiraj, P.hD. (Entomology)
Nature of damage
First instar larva nibbles on the leaves
Second instar makes holes
Late instars eating the leaves completely
Symptom of damage
Defoliation
Distribution: India, Pakistan, Sri Lanka, Thailand, Laos, Malaysia, southern
half of Europe and parts of North Africa

7. Eggs laid in batches of
six on both surfaces of
the leaves
Body colour velvety black. It
has a pair of reddish anal
processes
Pupates in loosely threaded
silken cocoon, on the ground
amongst wrapped up leaves
Dr. U. Pirithiraj, P.hD. (Entomology)

8. Forewings are pale-reddish brown.
Hindwings possess a medially white patch
and three large white patches on the outer
margin on a black background
Achaea janata
Dysgonia algira
Forewing with white band,
hindwing with a white median
band and grey outer margin.
Dr. U. Pirithiraj, P.hD. (Entomology)

9. Castor slug caterpillar, Latoia (=Parasa) lepida,
Cochlidiidae, Lepidoptera
3
Dr. U. Pirithiraj, P.hD. (Entomology)
Nature of damage
The slug-caterpillars feed on the leaves.
Young they remain in clusters and feed by
scrapping the green matter of the leaves on
the underside
Symptom of damage
Defoliation
It is a native minor pest found in the Indo-Malayan region, including India,
Sri Lanka, Vietnam, Malaysia and Indonesia

10. Eggs laid in batches of 20-30 on
the lower surface of leaves
A caterpillar is fleshy with yellowish-green
body bearing a greenish blue stripe it is called
blue-striped nettle grub. There are six rows of
spiny scoli on the dorsal surface while the
ventral body surface is flat. The spines are
highly irritating to touch
Pupation takes place on the tree trunk in
a hard shell-like, elliptical
Wings are greenish in colour fringed with
brown patches along the margins
Dr. U. Pirithiraj, P.hD. (Entomology)

11. Hairy caterpillar, Euproctis fraterna, Eribidae
(Lymantriidae), Lepidoptera
4
Dr. U. Pirithiraj, P.hD. (Entomology)
It is found in the Maldives, India, Sri Lanka and the Seychelles
Symptom of damage
Defoliation
Nature of damage
Caterpillars feed on the leaves

12. Full grown larva has red head and dark reddish
brown body covered with white hairs
Pupation takes place
inside the plant in a
yellowish cocoon
Medium sized, yellowish colour with
pale transverse lines and three black
spots on the border of the forewings
Dr. U. Pirithiraj, P.hD. (Entomology)

13. Hairy caterpillar, Olene mendosa (Dasychira
mendosa), Eribidae (Lymantriidae), Lepidoptera
5
Dr. U. Pirithiraj, P.hD. (Entomology)
Symptom of damage
Defoliation.
Nature of damage
Caterpillars feed on
the leaves.
Larva is greyish brown in
colour with dark prothoracic
and pre-anal tuft of hairs.
Pupates in a yellowish
silken cocoon
Bigger, yellowish
brown moth with
bulged abdomen
Eggs are off-white
with brown tops
It is found in India, Bangladesh, Sri Lanka, Indonesia, Taiwan, Thailand and Australia.

14. Hairy caterpillar, Somena scintillans (Porthesia
scintillans), Eribidae (Lymantriidae), Lepidoptera
6
Dr. U. Pirithiraj, P.hD. (Entomology)
Symptom of damage
Defoliation.
Nature of damage
Caterpillars feed on the leaves
Larva has yellowish brown
head. There are tufts of
hairs on the segments
between the true legs and
prolegs
Pupates in a yellowish silken cocoon
Forewings are brownish
with yellow spots on the
border
It is found in northern India, Sri Lanka, Myanmar and the Andaman Islands

15. Castor butterfly, Spiny caterpillar, Ariadne merione
(Ergolis merione), Nymphalidae, Lepidoptera
7
Dr. U. Pirithiraj, P.hD. (Entomology)
Symptom of damage
Defoliation
Nature of damage
Caterpillars lie on the upper
surface of the leaf. It feeds from
margin and cause defoliation
Species is found in South and Southeast Asia.

16. Brown colour with black wavy lines on wings
Sculptured eggs laid singly on
the leaves
Green body covered with branched hairs
and yellow stripe on dorsal side
Brownish chrysalis pupa Dr. U. Pirithiraj, P.hD. (Entomology)

17. Wooly bear, Olepa ricini (Pericallia ricini), Arctiidae,
Lepidoptera
8
Dr. U. Pirithiraj, P.hD. (Entomology)
Symptom of damage
Defoliation
Hindwings are pink or red
colour with black spots
Blackish brown
larva with red
head
Round and light
yellow
It is found in Bangladesh, India, Nepal, and Sri Lanka.
Nature of damage
Caterpillar feeds on the leaves
Brownish pupa

18. Tussock caterpillar, Orygyia postica (Notolopus
postica) , Eribidae (Lymantriidae), Lepidoptera
9
Dr. U. Pirithiraj, P.hD. (Entomology)
Symptom of damage
Defoliation
Nature of damage
Caterpillars of the moth feed on the leaves
Eggs are laid in clusters

19. Small adult with brown wings
Full grown larva possess a brown head, a pair of
long pencil of hairs projecting forwardly from the
prothorax, yellowish tuft of hairs arising from the
lateral side of the first two abdominal segment
and long brownish hairs arising from 8th
abdominal segment.

20. Sap feeders

21. Leafhopper, Empoasca flavescens, Cicadellidae,
Hemiptera
10
Dr. U. Pirithiraj, P.hD. (Entomology)
Throughout the tropics, subtropics and temperate areas
Nymphs and adult suck phloem sap from leaves

22. Whitefly, Trialeurodes ricini, T. rara, Aleyrodidae,
Hemiptera
11
Dr. U. Pirithiraj, P.hD. (Entomology)
Africa, the Middle East and Asia
Symptoms: Water soaked spots on the leaves

23. Thrips, Retithrips syriacus, Thripidae, Thysanoptera
12
Dr. U. Pirithiraj, P.hD. (Entomology)
Nymphs carries fecal matters
Damages the leaves
Widespread in Africa and India

24. Gall fly, Asphondylia ricini, Cecidomyiidae, Diptera
13
Dr. U. Pirithiraj, P.hD. (Entomology)
Damage is caused by maggots
As a result of feeding by them,
the buds develop into galls and
produce no fruits and seeds