2012 Annual Report
1a.Objectives (from AD-416):
The objective of this research is to perform genome-wide analysis of several members of the Oriental fruit fly species complex with focus on:
• Identification of gene regions for use in species-level diagnosis based on these genomes
• Identification of gene regions that demonstrate poor performance for diagnostics (and should not be included in screening studies)
• Identification of population-level markers for pathway analysis and population structure studies (these markers should be useful across species boundaries and provide markers for various bactrocera and fruit fly species)
• Comparative phylogenomics analysis of the included species to direct future studies and test species boundaries
1b.Approach (from AD-416):
Comparative genomic analysis within the dorsalis complex will be performed by using pyrosequencing technology to generate several “shallow” (low coverage) genomes from Bactrocera species and analyze them using bioinformatic tools. Using five-ten fruit fly specimens representing Bactrocera species in the dorsalis complex our team will generate genomic databases for each specimen using a 454 pyrosequencer operated at the University of Hawaii. This genomic work will be designed and supervised by a PBARC research entomologist who is currently in charge of annotating the completed Bactrocera dorsalis genome. The species included for genomic analysis will be selected based on similarity to B. dorsalis, economic significance, and value to SIT programs. The data generated using 454 technology will be edited, annotated and analyzed by CPHST and ARS staff.
The goal of this research is to perform genome-wide analysis of several members of the Oriental fruit fly species complex which contributes to Objective 5 of the in-house project.
High throughput sequencing of approximately 48 populations of Bactrocera dorsalis have been completed. This includes samples from throughout South East Asia, as well as collections from the four major Hawaiian Islands through additional collecting that was completed this fiscal year. DNA extractions, library preparation, barcoding and sequencing was completed. Initial analysis of the data reveals about 20,000 loci that appear to be informative to identify populations of B. dorsalis, but more detailed analysis still needs to be completed. All of the data is loaded on a mysql database to facilitate data sharing and interactions.
Throughout the year, communication between USDA-ARS, USDA-APHIS, and collaborators providing samples for sequencing have been ongoing through email communication and teleconferencing to manage progress and funding availability. This includes the arrangement of samples being sent from IAEA to USDA-ARS through the organization of USDA-APHIS. In addition, this project was discussed in detail at a workshop held at USDA-APHIS-CPHST, Edinburg, Texas, in January 2012.