![]() The diapause duration is programmed by the brain and can readily be transferred to other pupae by brain transplantation. ![]() This mechanism apparently functions in synchronizing the initiation of adult development among individuals that pupate at different times. Observations with field-reared hornworms are consistent with the model: September hornworms receive more short-day cycles than August hornworms and thus have a shorter diapause. Such manipulations consistently support a model in which diapause duration is inversely related to the number of short-day cycles received. ![]() The number of short-day cycles the hornworms receive can be varied by partial starvation and the use of different rearing temperatures. Hornworms transferred from long-to short-day conditions at later stages of larval development enter diapause at a lower rate, but the resulting diapause is of greater duration. Short daylength throughout embryonic and larval development yields a high diapause incidence, but a diapause of short duration. Daylength monitored by the embryos and larvae of the tobacco hornworm, Manduca sexta, is used to program both the incidence and duration of pupal diapause.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |