Bionomics of Teak Leaf Skeletonizer, Eutoctona Machaeralis Walker (Pyrallidae: Lepidoptera) Under Laboratory Conditions

The laboratory studies on the bionomics of teak leaf skeletonizer, Eutoctona machaeralis Walker was indicated that a female laid on an average 223.4 eggs singly or in batches near midrib of leaves or on undersurface of leaves. The preoviposition, oviposition and post-oviposition period lasted for 3.2, 4.4 and 2.4 days, respectively. Incubation period lasted for 4.0 days with 92.65 per cent egg hatching. The first instar larva was greenish white with head breadth 0.24 mm and body length 1.28 mm. The larval development completed within 12.9 days through five instars, duration of each instar observed to be 2.2, 2.4, 2.5, 2.3 and 3.6 days, respectively. The full grown larva measured 1.61 mm in head breadth and 21.9 mm in body length. Pre pupal and pupal period lasted for 1.5 and 6.1 days, respectively. Longevity of male and female moths was 5.8 and 7.1 days, respectively. Male moth measured 11.67 mm in length, 1.95 mm in width and 24.39 mm in wing expanse whereas female moth measured 9.71 mm in length, 2.91 mm in width and 19.58 mm in wing expanse. The sex ratio for male and female was 1: 1.77. The life cycle was completed within 23.01 days.