Evaluation of different plant oils against Lasioderma serricorne Fab. on fennel

A laboratory experiment was conducted during 2007-2008 at SKN Agricultural University, Jobner on evaluation of different plant oils viz., neem, karanj, mustard, groundnut, lemongrass and citronella oils (0.1, 0.5 and 1.0 ml/100g seeds) and one chemical, malathion (0.025, 0.050 and 0.075 per cent) against Lasioderma serricorne on fennel seeds. The malathion at all concentrations was found to be most lethal, causing cent per cent mortality of adults. Neem oil was found to be most effective in increasing the developmental period (78.23 days) and reducing adult emergence (19.02 per cent), longevity of adult (male: 11.1 days and female: 12.0 days), seed damage (5.10 per cent), weight loss (2.60 per cent) followed by karanj and lemongrass oils at 1.0 ml/100g