Project Number: 5442-22000-039-00
Project Type: Appropriated

Start Date: May 25, 2005
End Date: May 24, 2010

Objective:
Provide molecular genetic data defining biosystematics and population diversity (including Wolbachia dispersal) of pest and beneficial insects such as Diabrotica, Aphthona, Lygus et al. Determine the molecular mechanisms of diapause initiation and termination in insects especially leaf beetles and pollinators. Identify conserved sequence motifs associated with diapause specific genes, determine if products (e.g. noncoding RNAs) are produced, and examine the distribution and diversity of the sequences across insect species.

Approach:
Measure nuclear genetic diversity using microsatellite and AFLP markers. Use mtDNA PCR-RFLP and sequencing to quantitate additional diversity and identify species. Monitor the movement of Wolbachia strain boundaries over several seasons. Define the level of competition between insects infected with different Wolbachia strains and correlate Wolbachia infection, mtDNA genotype, and sex ratio. Identify and Characterize genes differentially expressed in diapause and non-diapause insects. Use interfering RNA (iRNA) experiments to determine the significance of key genes in diapause physiology. Measure respiration quotients at different temperatures and stages of diapause to determine the transition from a diapause respiration pattern to a nondiapause pattern. Conduct comparative study of diapausespecific genes and their regulatory elements in other insects based on primers derived from the original Colorado potato beetle diapause regulated genes.