Figure 2.

Life cycle of the tobacco stem weevil (T. mucorea Champion, G.C.). T. mucorea weevils undergo complete metamorphosis. During March and April, adult T. mucorea females lay eggs on stems of N. attenuata plants from which larvae hatch and burrow into the stem, where they feed on the pith during their entire larval development which lasts for 4 to 5 instars. In the beginning of July, last instar larvae, excavate a partial exit hole through the vascular and epidermal layers of the stem and pupate. The next generations of adult weevils emerge from pupae in August and September and overwinter in the dried and senescent N. attenuata stems or in other protected cavities.