Abstract:
A laboratory experiment was conducted to study the efficacy of nuclear polyhedrosis
virus (NPV) with nine concentrations on larval mortality, incubation period, rate of pupation,
pupal mortality and emergence of malformed and normal adults of all instars of Plutella xylostella
L. The incubation period of the virus increased and mortality decreased with advancement in age
of the caterpillars. Pupation rate and mortality decreased with increase in polyhedral inclusion
bodies in all instars. Higher percentage of malformed adult emergence was observed with lower
concentration of virus infection in early instars. Normal adult emergence was higher in lower
concentrations of virus fed to the early instars.
