FLIGHT ACTIVITY OF PLUSIA GAMMA IN THE LABORATORY

Abstract

Aktograph experiments showed lowered light thresholds for flight during the first three days after emergence of adult moths. Maximum flight duration was also reached at the third day. These three days probably represent the time when migration would occur in wild insects.Migration of insects usually begins post tenerally so it should be possible to direct migratory behaviour (i.e. the tendency for continued flight) in young adults of each generation of a species that migrates. The flight behaviour of Plusia gamma L. was studied in the laboratory to test this possibility.RésuméACTIVITÉ DE VOL DE PLUSIA GAMMA AU LABORATOIREDes expériences utilisant un actographe ont montré une inhibition moins forte de la lumière sur le vol pendant les trois premiers jours suivant leur émergence. La durée maximum de vol est atteinte au 3ème jour. Il est suggéré que ces premiers trois jours de la vie imaginale pendant lesquels le papillon a tendance à voler de facon continue, correspondent à la période d'activiTÉ migratoire.