Recent climate change enhanced the northward expansion of animal distribution. In insect, flight ability brought them the highly dispersal potential. However, female’s flight ability is sometimes restricted as increasing their age. It was considered that this phenomenon was due to the existence of the trade-off between flight ability and reproduction (oogenesis-flight syndrome). A. fics (Lepidoptera, Noctuidae) is a critical pest for Fics, and invader from south country. Previous study observed that this species had high flight ability and indicated the oogenesis-flight syndrome.
Therefore, we studied this species to obtain the physiological mechanism of oogenesis-flight syndrome. We hypothesized the reduction of flight activity previously observed in females were due to the restriction of energy substance represented as lipids. We first measured the expression of the vitellogenin , the major yolk protein, as the indicator of ovarian maturation using a SDS-PAGE. Then we calculated the amount of TAG, the storage form of lipids, as a indicator of the flight ability using an Iatroscan.
In this study, we consider the trade-off between flight ability and reproduction dealing with the vitellogenin expression and the amount of TAG. However, these two indicators may be results from the primary regulation mechanism such as endocrine system or epigenetics, …etc. Thus, uncovering these mechanisms are essential for further understanding this trade-off. However, mechanisms underlying in this trade-off seems too complicated. Therefore, the simplified theoretical model is required to understand this problem.
Locusts have distinct two phenotypes which called solitarious and gregarious. It is considered this phenomenon reflects the trade-off between the reproduction and dispersal. In addition, this species is well-studied model insect. Thus, for further theoretical approach, we introduce the knowledge of previous locust endocrinology or epigenetics.