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Poster: Diseases of Plants: Disease Detection & Diagnosis


Developing an innovative molecular toolbox for identification of Phytophthora species with emphasis on species of regulatory concern.
Z. Abad (1), J. Bienapfl (1), L. Knight (1), K. Jennings (1), M. Galvez (1), L. Schena (2) (1) USDA APHIS PPQ S&T, U.S.A.; (2) Mediterranean University of Reggio Calabria, Italy

The genus Phytophthora consists of 155 species, many of which cause significant economic impact to crops, ornamentals, and forest ecosystems worldwide. Many species are also exotic and of regulatory importance for the USA. Accurate species identification can be extremely challenging due to the need for extensive training and experience, as well as many misidentified DNA sequences deposited in public databases. In order to facilitate correct identification of Phytophthora species, we are pioneering work with international collaborators for the implementation of a “Molecular Toolbox” containing DNA sequences generated from the type specimens used for the original descriptions. Ten nuclear genes and five mitochondrial genes currently used for identification and phylogenic studies have been evaluated. Six nuclear genes, including the YPT1 gene that is amplified with new primers developed by Schena, and one mitochondrial gene have been selected for use in our “Molecular Toolbox” based on their utility in the robust identification and phylogenetic studies of Phytophthora species. However, many of the types lack sequences for these different genes (over 50%) and predominantly only have ITS sequences available. We will provide all files generated from the DNA sequencing, which will also demonstrate the high quality of data generated, to be used for identification purposes. Emphasis of this project is for species of high economic impact and regulatory concern for the USA.