Castor: Insect Pests Management

Red headed hairy caterpillar

• Egg: The female moth lays its eggs in clusters on the under-sides of leaves and covers them with pale brown hairs. The incubation period lasts from 5 to 10 days.
• Larva: The newly hatched larvae feed gregariously and after a few days feed on the leaves independently. Larva has red head, body covered with long dense, reddish brown hairs. Both anterior and posterior ends have black broad bands (hairs) with a reddish area in the middle.
• Pupa: The pupa resembles is mostly darker in color, although it sometimes is yellowish in color. The pupa bears spiny hairs on the posterior end. Pupa undergoes diapause during winter. The larval period varies from 15 to 85 days and the pupal period 7 to 20 days.
• Adult: The pest is active throughout the year and has several generations. Adult moths have dirty white forewings and milky white hind wings with black spots. Forewings have a reddish brown band along coaster margin. The peak period of activity is August-September

• Scrap under surface of leaves when they are in neonate stage. The scrapped patches of the leaves becomes thin and papery
• Full grown larvae devours entire foliage and flowers causing defoliation and affecting fruit setting and often migrate from one field to another devastating whatever crops come their way.
• After about 30-40 days of feeding the larvae burrow into soil, usually in the undisturbed soil of field or non-cropped areas and pupate.

• Parasitoids: Trichogramma spp., Enicospilus sp
• Predators: Chrysoperla zastrowi sillemi, ladybird beetle, reduviid bug, spider, red ant, robber fl y, black drongo (King crow), common mynah, big-eyed bug (Geocoris sp), earwig, ground beetle, pentatomid bug (Eocanthecona furcellata), preying mantis etc.

Castor semilooper

This is a serious pest of the oilseed crop and is distributed throughout the Indian Union, wherever castor is grown. It occurs during July to September

• Egg: The female moth lays around 450 blue green rounded eggs singly on the leaves of the castor plant at night. The eggs are laid singly on both sides of the leaves. Four to six eggs have been observed on each leaf. The egg when freshly laid is round, pale green in colour and measures about 0.9 mm in diameter. The chorion is full of ridges and furrows. The egg is convex on the upper surface and concave below. The incubation period of the egg varies from 2 to 5 days from July to September.
• Larva: The newly hatched caterpillar is yellowish green in colour with light brown head and thorax and measures 3.5 mm long. The full grown larva is dull greyish brown and measures 60 to 70 mm long. Five distinct larval instars are present. The larval period lasts from 12 to 13 days in July, August and September.
• Pupa: Pupation takes place either in the soil amidst the fallen leaves or sometimes amidst the folded leaves on the plant. The pupal period lasts from 10 to 27 days.
• Adult: Adults are grayish-brown in colour. Forewings have pale reddish brown patch. Black hind wings have white stripes in the middle and 3 large white spots on outer margin.

A generation is completed in about 28 to 45 days

• Freshly hatched larvae feed gregariously, scraping the chlorophyll, soon disperse.
• Sometimes the feeding is so heavy that only petioles and branches are left behind.
• Caterpillars feed on the leaves and cause sometimes complete devastation of the crop.
• Damage to defoliation.

• Parasitoids: Trichogramma achaea, T. minutum, T. evanescens, Microplitis spp.
• Predators: Chrysoperla zastrowi sillemi, ladybird beetle, reduviid bug, spider, red ant, robber fly, black drongo (King crow), common mynah, big-eyed bug (Geocoris sp), earwig, ground beetle, pentatomid bug (Eocanthecona furcellata), preying mantis etc.

Tobacco caterpillar

The pest has a wide distribution throughout the Indian Union and occurs as a sporadic pest. Active during August to October

It is found throughout the tropical and subtropical parts of the world, wide spread in India. Besides tobacco, it feeds on cotton, castor, groundnut, tomato, cabbage and various other cruciferous crops.

• Egg: Female lays about 300 eggs in clusters. The eggs are covered over by brown hairs and they hatch in about 3-5 days.
• Larva: Caterpillar measures 35-40 mm in length, when full grown. It is velvety, black with yellowish – green dorsal stripes and lateral white bands with incomplete ring – like dark band on anterior and posterior end of the body. It passes through 6 instars. Larval stage lasts 15-30 days
• Pupa: Pupation takes place inside the soil. Pupal stage lasts 7-15 days.
• Adult: Moth is medium sized and stout bodied with forewings pale grey to dark brown in colour having wavy white crisscross markings. Hind wings are whitish with brown patches along the margin of wing. Pest breeds throughout the year. Moths are active at night. Adults live for 7-10 days. Total life cycle takes 32-60 days. There are eight generations in a year.

• The early instar larvae feed gregariously on the under surface of the leaf by scrapping off the chlorophyll leading to appearance of papery membranes
• Later they disperse, become solitary and nocturnal and cause complete defoliation
• They also feed on the flower buds, flowers.

• Parasitoids: Trichogramma spp., Tetrastichus spp., Telenomus spp., Chelonus spp., Bracon spp., Ichneumon spp., Carcelia spp., Campoletis spp.
• Predators: Chrysoperla zastrowi sillemi, ladybird beetle, reduviid bug, spider, red ant, robber fly, black drongo (King crow), common mynah, big-eyed bug (Geocoris sp), earwig, ground beetle, pentatomid bug (Eocanthecona furcellata), preying mantis etc

Shoot and capsule borer

The pest is distributed throughout the plains and the hills of the Indian Union. Infestation starts from flowering stage. Usually active during Nov-March

• Egg: The female moths lay eggs on the tender parts of the plant.
• Larva: Pale greenish with pinkish tinge and fi ne hairs with dark head and prothoracic shield. The caterpillar that hatches out bores into the shoot if the plant is young and knit the seed capsules if the plant is old. The full-grown caterpillar is stout, reddish brown in colour and measures 15 to 25 mm. long. It pupates in a silken cocoon.
• Adult: Adults have yellow wings with black dots

• The caterpillars bore into shoot and seed capsules and cause extensive damage to the crop and characteristic webbing of capsules along with excreta is seen.
• Capsules with bore holes
• Damaged capsules webbed together
• Peduncle and capsules having galleries made of silk and frass.

• Parastioids: Bracon brevicornis, Brachymeria euploeae
• Predators: Chrysoperla zastrowi sillemi, ladybird beetle, reduviid bug, spider, red ant, robber fly, black drongo (King crow), common mynah, big-eyed bug (Geocoris sp), earwig, ground beetle, pentatomid bug (Eocanthecona furcellata), preying mantis etc.

Bihar hairy caterpillar

This pest occurs during October to December and of late it is also occurring from July. In recent years, it has become an important pest on groundnut also.

• Egg: Female lays eggs in masses on lower surface of leaves.
• Larva: The larvae are pale yellow coloured with yellow hair over the body. They are polyphagous, feed on leaves and cause loss by way of defoliation. In severe cases only stems are left behind. In defoliated crops it also feeds on capsules.
• Pupa: Pupates in leaf litter close to the plants. There are several generation per year.
• Adult: Adult moth is reddish brown with black spots. Both the wings are pinkish and possess black spots

• Young larvae feed gregariously mostly on the under surface of the leaves.
• Feed on leaves and cause loss by way of defoliation.
• In severe cases only stems are left behind.
• In defoliated crop it also feed on capsules.

• Predators: Chrysoperla zastrowi sillemi, ladybird beetle, reduviid bug, spider, red ant, robber fly, black drongo (King crow), common mynah, big-eyed bug (Geocoris sp), earwig, ground beetle, pentatomid bug (Eocanthecona furcellata), preying mantis etc.

Jassid

The castor jassid occurs on castor as a minor pest. It has been recorded from Bihar, Tamil Nadu and Assam. Outside India it has been recorded in Burma. Besides castor it infests tea. Peak infestation of jassid is during November to January. Mostly seen at seedling stage, sometimes found almost throughout the year

• Egg: Female inserts eggs into leaf veins on the underside. Eggs hatch in 6-10 days and nymphal period is 7-9 days.
• Nymph: Nymphs are pale greenish almost translucent and walk diagonally. Nymph stage lasts for 7-21 days.
• Adult: Adults are greenish yellow, wedge shaped with a pair of black spots on vertex and a black spot on each of the forewings. Adult stage lasts for 35-50 days. There are a total of 7-8 generations in a year.

• Nymphs and adults suck sap usually from the under surface of the leaves and inject toxin causing curling of leaf edges and leaves turn red or brown. The leaves dry up and shed.
• Leaf margins become yellow
• Curling of leaf edges and leaves turn red or brown
• Leaves dry up and shed.

• Predators: Dicyphus hesperus, Chrysoperla zastrowi sillemi, ladybird beetle, big-eyed bug (Geocoris spp.) etc.

Castor slug

It is most common in the southern regions of the country especially Madras and has been recorded from Ceylon also. This pest damages the castor plant sporadically.

• The female moth lays flat scaly eggs on the tender parts of the plant in small clusters.
• The full-grown caterpillar measures 15-25 mm in length.
• Thick short spiny hairs out of rows of warts on the body.
• It is bright green in colour and has interrupted blue stripes on the dorsum.
• It moves like a slug.
• Pupation takes place in a hard greyish cocoon on castor stem or the trunks of its other host plants.
• The pupal period lasts from three to five weeks or longer.

• The caterpillars are spiny and when touched, cause irritation to the skin.
• To begin with, they feed gregariously on the leaves of castor and later spread over to the entire plant.

• Predators: Chrysoperla zastrowi sillemi, ladybird beetle, reduviid bug, spider, red ant, robber fly, black drongo (King crow), common mynah, big-eyed bug (Geocoris sp), earwig, ground beetle, pentatomid bug (Eocanthecona furcellata), preying mantis, Dicyphus hesperus etc.

Whitefly

The castor whitefly is a pest of castor in some regions of our country. It is more commonly found in Bihar, Bombay, Andhra and Madras. Sometimes the damage caused by this pest to castor crop is serious. More serious in summer months (March to May) Temperature of 30 °C with high relative humidity favours multiplication of the pest

• Egg: The female lays shining white long eggs in small clusters or scattered about on the underside of tender leaves.
• Nymph: The eggs hatch into nymphs which settle on the leaves and along with the adults suck the sap from the leaves. Both the nymphs and the pupa are yellowish in colour.
• Adult: The adult fly has white wings, yellow body and pale white legs and antennae. It is a tiny insect a little less than a millimeter in length.

• Both nymphs and adults suck sap from leaves.
• This makes the leaves appear sickly and sooty mould is developed a whitefly infestation is severe.
• Water soaked spots on the leaves and become yellow and dry up
• Leaves appear sickly and get coated with sooty mold
• Stunted plant growth, shedding of fruit bodies

• Parasitoids: Encarsia formosa, Eretmocerus spp., Chrysocharis pentheus
• Predators: Chrysoperla zastrowi sillemi, ladybird beetle, reduviid bug, spider, red ant, robber fly, black drongo (King crow), common mynah, big-eyed bug (Geocoris sp), earwig, ground beetle, pentatomid bug (Eocanthecona furcellata), preying mantis etc

Thrips

• Adult and nymph: Very tiny pinkish nymphs and black adults with fringed wings

• Both adults and nymphs feed on the upper and lower surfaces of the leaves.
• The terminal leaves crinkle and appear silvery.
• If infestation is severe, stunted growth results.
• The injury results in development of dull yellowish green patches on the upper surface as brown necrotic areas of the lower surface
• Leaves get curl and plant gets stunted.

• Predators: Predatory mite, predatory thrips, Oligota spp., Orius spp. (pirate bug), hover fly, mirid bug etc.

IPM for Castor

To know the IPM practices for Castor, click here.

Source: NIPHM and Directorate of Plant Protection, Quarantine & Storage