5. Stem borer: Enarmonia tricentra (Eucosmidae: Lepidóptera)

Damage symptoms

Larvae bore the stems, branches and inflorescence. The top shoot leaves becoming shrivelled and the bored stem swollen into a sort of gall.

Bionomics

The full-grown larva is about 9 mm long and 1-5 mm broad, cylindrical, moderately stout, pale yellow. When full-fed and about to pupate, the larva becomes bright pink in colour. Pupation takes place in a white cocoon formed inside a rolled leaf. The pupa is about 4-5 mm long and 1-5 mm broad, rather stout, shiny yellow-brown. The pupal period is about a week