Biology of Gesonia gemma (Swinhoe) on Soybean

A female laid eggs from 149 to 247 (Av. 182 ± 36.97) on the upper surface of the leaves. Most of the eggs were deposited near midrib and basal part of the leaves. There were 5 larval instars, differing in colouration. Fully grown larvae measured 18.0–22.0 mm in length and 2.0–2.5 mm in width. Prolegs were present on 4^th, 5 ^th, 6 ^th and last abdominal segment. The duration of the egg, larval and pupal periods was 2–3, 9–17 and 7–8 days, respectively. The total duration from egg to adult emergence was completed in 18–28 days. The size of the pupa was 8–9 mm in length and 1.9 to 2.1 mm in width. Female pupa was comparatively long in size than male. Medium sized moth measuring 6.0–8.0 mm body length 15.0–17.0 mm wing expand. The longevity of adult male and female was 3 to 6 and 2 to 8 days, respectively.