U.S. Pacific Basin Agricultural Research Center
64 Nowelo St.
Hilo, Hawaii 96720
Ph: (808) 959-4335
Fax: (808) 959-5470
via ARIS System
via Google Scholar
My research focuses on utilizing genomic and molecular techniques to conduct research that supports the development and implementation of environmentally acceptable and sustainable strategies for management of tropical insect pests in support of Hawaii, the Pacific Basin, and U.S. agriculture. In particular, I perform fundamental research on the genomics of fruit flies, with focus on the oriental fruit fly (Bactrocera dorsalis) and related species. The goals of my research are to develop a foundation of information on the genomics structure of Bactroceraflies and utilize this information to develop new and novel sustainable means of managing tephritid fruit fly species. Development of techniques to improve survey, detection, and mass rearing (for sterile insect technique (SIT) implementation), as well as identifying target genes for novel control strategies are of particular interest.
Next generation sequencing technologies are being used to analyze the genome of the oriental fruit fly. Whole genome shotgun approaches are being used to create a high coverage assembly of this species using the 454-Titanium pyrosequencing technology. In addition, high coverage transcriptome/RNA-seq analysis is being performed and a BAC library has been established for use in establishing various aspects of functional genomics of this species. The goal of this project is to identify unique and specific gene-level targets that could be used to develop novel control methods for the oriental fruit fly in the field, as well as allow for improvement to mass rearing and SIT.
Bactrocera is an economically important genus of fruit flies in the family Tephritidae. It includes many species that are of agricultural significance. Accurate identification of tephritid species is important for maintaining interception records that are useful for pathway analysis and resolving trade disputes. Unfortunately, fruit fly identification of intercepted larvae (detected in fruit at ports of entry) is problematic because larvae lack suitable characters for diagnosis. Although molecular DNA techniques based on mitochondrial markers (e.g., DNA barcodes) are useful for the diagnosis of many fruit flies, this technology does not diagnose many important pests within Bactrocera that belong to species complexes such as the B. dorsalis species complex. Recent taxonomic work on this complex suggests that it includes over 50 species of which eight are considered of high economic significance. Most of these species have restricted geographic ranges within the Indonesian Archipelago but some pest species such as B. dorsalis, B. carambolae, B. papayae and B. invadens have broader distributions. Discrimination of B. dorslais, B. papayae, and B. philippinensis has been especially problematic for many previous molecular diagnostic studies using DNA barcodes and other methodologies.
Diagnostic marker development has traditionally relied on a laborious screening process in which putative regions of the genome are targeted and analyzed sequentially. This process is usually efficient for distantly related species but can become complicated for closely related species that share genetic types. One alternative approach to marker development that has emerged recently is the use of second generation sequencing (e.g., genomics) and bioinformatics to identify putative genetic markers. This technology generates many potential diagnostic characters simultaneously and relies on computational tools to search large databases for useful markers. The data generated from this approach can be used to develop species-level markers useful for pest identification and population-level markers useful for studying population geneticsof the species. It can also generate systematic information useful for evaluating species limits of cryptic species.