VITELLOGENIN LEVELS IN ALLATECTOMIZED FEMALE CRICKETS, GRYLLUS-BIMACULATUS DE GEER (ENSIFERA, GRYLLIDAE)

Allatectomy of cricket nymphs up to 24 h after the moult to the last i nstar resulted in moulting to normal adults which laid a low number of eggs. No juvenile hormone III and no vitellogenin were detected in th e haemolymph of allatectomized females by means of CC-mass spectrometr y (MS) and rocket immunoelectrophoresis, respectively, whereas the egg s contained the normal pattern of vitellins as judged by SDS-PACE. Ova riectomy of previously allatectomized females led to a moderate accumu lation of vitellogenin in the haemolymph. Administration of the juveni le hormone analogues hydroprene, methoprene, and fenoxycarb to allatec tomized females restored egg production to a variable extent. Injectio ns of 20-hydroxyecdysone increased haemolymph vitellogenin titer of al latectomized females, but did not affect the number of produced eggs. Treatment with hydroprene and 20-hydroxyecdysone showed a synergistic effect. It is suggested that juvenile hormone does not have an all-emb racing control on vitellogenesis, though it does exert a marked quanti tative effect on vitellogenin synthesis and the rate of egg production . (C) 1996 Wiley-Liss, Inc.