Pheromone Chemicals

(Pink boll worm) – is a major pest of cotton. Adults are small, grayish brown, inconspicuous moths. When their wings are folded, they have an elongated slender appearance. The wing tips are conspicuously fringed. Young larvae are tiny, white caterpillars with dark brown heads. When mature, they are about 0.5 inch (12 mm) long and have wide transverse pink bands on the back. Eggs are very small, slightly elongated, and laid under the calyx of green bolls.

Identification of the pest:

Larva : Shows colour variation. Young larva are white and late instar becomes almost black, brown or green to pale or pink Several dark and light alternating bands running the entire length.
Adult Small moth : Forewings are brown or dull yellow olive grey with dark spots Hind wings margins are deeply fringed

Host plants :

Cotton

Damage :

Symptoms of damage : 1. Rosetted flowers. 2. Excreta observed at the point of bore holes by larval feeding. When bolls are opened, damaged seed kernel would be observed. 3. They cut window holes (interlocular burrowing) in the two adjoining seeds thereby forming "double seeds". 4. The attacked buds and immature bolls drop off. 5. Discolored lint and burrowed seeds.
Pink bollworms damage squares and bolls, the damage to bolls being the most serious. Larvae burrow into bolls, through the lint, to feed on seeds. As the larva burrows within a boll, lint is cut and stained, resulting in severe quality loss. Under dry conditions, yield and quality losses are directly related to the percentage of bolls infested and the numbers of larvae/boll. With high humidity, it only takes one or two larvae to destroy an entire boll because damaged bolls are vulnerable to infection by boll rot fungi.