Lipid utilization for ovarian development in an autogenous mosquito, Culexpipiens molestus (Diptera : Culicidae)

Citation
K. Sawabe et A. Moribayashi, Lipid utilization for ovarian development in an autogenous mosquito, Culexpipiens molestus (Diptera : Culicidae), J MED ENT, 37(5), 2000, pp. 726-731
Citations number
32
Categorie Soggetti
Entomology/Pest Control
Journal title
JOURNAL OF MEDICAL ENTOMOLOGY
ISSN journal
00222585 → ACNP
Volume
37
Issue
5
Year of publication
2000
Pages
726 - 731
Database
ISI
SICI code
0022-2585(200009)37:5<726:LUFODI>2.0.ZU;2-G
Abstract
During the first ovarian cycle, autogenous female mosquitoes develop their ovaries in the absence of blood feeding. In autogenous Culex pipiens molest us (Forskal), complete yolk deposition was observed 2 d after emergence, ev en when no feeding was allowed (starved). Neutral lipids in Cx. p. molestus increased during the pupal stage, abruptly declined after emergence, and a gain increased on day 3. In contrast, neutral lipids decreased in anautogen ous Anopheles stephensi (Liston) and Cx. p. pallens (Coquillett) and starve d females died within 2-3 d after emergence, nigh ratios of two major neutr al lipids, free fatty acid and triglyceride, were isolated by thin-la)er ch romatography (TLC) from the lipid contents of both Cx. p. molestus and An. stephensi fourth-instars and newly emerged females. Fatty acid analyses usi ng gas liquid chromatography (GLC) and GLC-mass spectrometry (GLC-MS) showe d higher proportions of unsaturated than saturated fatty acids in Cx;. p, m olestus at both stages and two major neutral lipids: free fatty acids and t riglycerides. The percentage composition of linoleic acid (C18:2), which is a precursor of arachidonic acid, was higher in Cx, p. molestus than in An. stephensi. Our results indicated that elevated lipid content before emerge nce may play a role of inducing ovarian development in autogenous mosquitoe s.