Variations in fuel use in the flight muscles of wing-dimorphic Gryllus firmus and implications for morph-specific dispersal.
Although a considerable amount of information is available on tradeoffs in wing-polymorphic insects, only limited data are available on the relationship between flight and biochemical variation within species. In the current study, we compared the biochemical basis in the dorsolongitudinal  flight muscle of the wing-dimorphic sand cricket, Gryllus firmus Scudder, with respect to tradeoffs in energy resources related to morph-specific flight, including glycogen, trehalose, and triglycerides. Our results show that levels of glycogen and trehalose in long-winged adults (LW[f]) were  significantly higher before dispersal, on days 5 and 7. Considering that this is the period during which long-winged adults are flight-capable, these results suggest that both glycogen and trehalose are important to flight. However, levels of triglycerides in short-winged crickets (SW) were  higher than in long-winged crickets, suggesting that triglycerides are not directly related to initial flight. In SW adults, triglyceride content on days 5 and 7 was significantly higher just before lights off than at the same time on day 1 or at any other time after lights on all other days.  This suggests that triglycerides are probably related to reproductive behaviors, such as mating and oviposition, in the SW morph. In addition, flight muscle water content was significantly lower in the LW(f) morph than in the SW morph.
Department of Entomology, College of Agriculture and Biotechnology, China Agricultural University, Beijing, China.
Bao-Chang
BC
Zhang
Cheng-Ji
CJ
Jiang
Chun-Ju
CJ
An
Qing-Wen
QW
Zhang
Zhang-Wu
ZW
Zhao
D000818:Animals; D004734:Energy Metabolism; D005426:Flight, Animal; D006003:Glycogen / Q000378:metabolism; D006135:Gryllidae / Q000033:anatomy & histology / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D018482:Muscle, Skeletal / Q000033:anatomy & histology / Q000378:metabolism; D010641:Phenotype; D012098:Reproduction; D014199:Trehalose / Q000378:metabolism; D014280:Triglycerides / Q000378:metabolism; D014921:Wings, Animal / Q000033:anatomy & histology / Q000378:metabolism
D014280:Triglycerides; D006003:Glycogen; D014199:Trehalose