1. Jute Mealy-bug: Phenacoccus hirsutus (Pseudococcidae: Hemiptera)
Distribution and status: Jute tracts of India. Major pest
Host range: Jute, roselle fibre crop (Hibiscus sabdariffa), an important fibre allied to jute.

Bionomics

The mated females lay pink cylindrical eggs on plants inside the ovisacs Egg period varies from 7 to 14 days. Nymphs emerge from the ovisacs in batches, corresponding with the sequence of egg-laying. The tiny nymphs crawl out on the host and select a suitable spot to settle down. They are light pinkish and secrete both a white mealy powder and honey-dew. The full-grown nymph secretes fine white mealy fibres with which it forms a cocoon and then pupates in it. The females remain wingless, and on maturity, they develop ovisacs in which eggs are laid. The female is a rotund, sac ­like, light pink creature and measures about 3 mm in length. The males are slender and have a pair of delicate wings.

Damage symptoms

The nymphs and females feed on the apical parts of a plant which becomes stunted and shows bushy-top symptoms. The petiole becomes shortened, the lamina crumples and the internodal length is reduced, resulting in fibre deterioration and yield reduction.

Management

• Conserve Scymnus pallidicollis (Coccinellidae) as it is the most efficient predator and feeds vigorously on the eggs, nymphs and adult females
• Spray 1.25 L dimethoate 30EC in 625 L of water per ha.