Biology of Tobacco beetle, Lasioderma serricorne (Fab.) on Turmeric

The female deposited eggs loosely on the surface of turmeric rhizomes. Eggs were pearl white in colour, oval with slight swelling in the mid region. There were small papillae like structures projecting at one end of the egg. When freshly laid, the eggs were translucent, smooth and shining. The average incubation period was 5.47 days. The larvae were creamy white in colour and thickly covered with fine hairs that appeared as light brown on fully grown individuals. The insect completed four larval instars before pupation. The larval duration ranged from 21 to 46 days with an average of 30.02 days. The larvae pupated within a cell made from food and waste material. The adults were small, oval, stout and reddish-brown beetles. The head was deflexed down, nearly at a right angle to the body, giving a humpback appearance. The studies on the biology of tobacco beetle through different seasons indicated that the mean developmental period for egg, larva and pupa of L. serricorne during the summer were 5.4, 26.26 and 5.67 days, respectively on turmeric, while they were extended (6.5 days for egg, 40.7 days for larva & 6.45 days for pupa) during the winter.