Volume 89, Issue 6
  • ISSN: 0002-9637
  • E-ISSN: 1476-1645



The vector competence and bionomics of form pipiens L. and f. molestus Forskäl were evaluated for populations from the Sacramento Valley. Both f. pipiens and f. molestus females became infected, produced disseminated infections, and were able to transmit West Nile virus. Form molestus females also transmitted West Nile virus vertically to egg rafts and F progeny, whereas f. pipiens females only transmitted to egg rafts. complex from urban Sacramento blood-fed on seven different avian species and two mammalian species. Structure analysis of blood-fed mosquitoes identified K = 4 genetic clusters: f. molestus, f. pipiens, a group of genetically similar hybrids (Cluster X), and admixed individuals. When females were exposed as larvae to midwinter conditions in bioenvironmental chambers, 85% ( = 79) of aboveground complex females and 100% ( = 34) of underground f. molestus females did not enter reproductive diapause.


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  • Received : 24 Apr 2013
  • Accepted : 10 Aug 2013

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