Insect Pests of Vegetable, Ornamental and Spice Crops (2+1)

Tobacco caterpillar

10. Tobacco caterpillar, Spodoptera litura (Noctuidae: Lepidoptera)

Distribution: Throughout the tropical and subtropical parts of the world.

Host plants: Polyphagous

Damage:

• Damage is caused by the caterpillars
• Feed on leaves and fresh growth.
• They are active at night and more serious on tobacco.
• Young caterpillars bite holes on leaves
• Older larvae defoliate entire foliage
• Fruits are also destroyed

Identification:

• Larvae: About 35-40 mm in length when fulfed .They are velvety black with yellowish green dorsal strips and lateral white bands.
• Adults: The moths are about 22 mm in length and about 40 mm across the wings. The fore wings have beautiful golden and grayish brown pattern

Life cycle:

• Each female may lay 300 eggs in clusters covered with brown hair.
• Eggs hatch in 3-5 days.
• Larvae become full fed in 15-30 days
• Pupal period is 7-15 days.
• Adult longevity is 7-10 days
• Total life cycle is completed in 32-60 days.
• 8 overlapping generations in a year.

Salient features:

• Breeds throughout the year, although development is retarded during winter.
• Each female may lay 300 eggs in clusters covered with brown hair.
• Young larvae feed gregariously initially
• Old larvae disperse to feed individually.
• Six larval instars.
• Pupation takes place in soil

Management:

• Clean cultivation to expose the larvae to natural enemies
• Pheromone traps to predict egg laying.
• Hand picking and destruction of egg masses and early gregarious instars.
• Spray of NSKE @ 4.0 per cent at early growth stage of the crop.
• Spray of SlNPV @ 250 LE per hectare
• Malathion (0.05%) in emergency.
• Natural enemies like Bracon sp, Telenomus sp , Bt and entomopathogenic fungi