thrice under laboratory conditions at 27±2oC and 65±5%
RH using CRD. As soon as possible the dead larvae were
removed from the beaker to prevent the rapid death of
further larvae, after 8, 16, 24 and 48 h. From the average of
three replicates, percentage mortality was counted by using
the following formula (Sumroiphon et al., 2006).