Tobacco stem borer
Larva small, whitish caterpillar, adult very small active brown moth. In bidi tobacco the female moth lays cylindrical eggs singly more on the upper surface than on lower and prefers laying towards the distal half of the upper surface and basal half of the lower surface. A female, on an average, lays 50- 80 eggs. Egg period 4 days, larval period 15-22 days. The full grown larva is pale white in colour, with head and thorax dark brown. The adults after emergence survive for 2-14 days. The total life-cycle extends over 4-5 weeks.
Tiny caterpillars mine along the leaf stalk into the stem and feed on the internal tissues. Due to larval feeding seedlings and young plants have stem galls and sprouted side branches; plants stunted, distorted and withered.