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Poster: Diseases of Plants: Disease Detection & Diagnosis


Loop-mediated isothermal amplification for the detection of soft rot causing Dickeya spp.
G. MARRERO (1), J. Yasuhara-Bell (2), M. Melzer (2), A. Alvarez (2) (1) University of Hawaii at Manoa, U.S.A.; (2) University of Hawaii at Manoa, U.S.A.

Dickeya spp. cause soft rot, wilt and blackleg diseases in a wide range of plants and crops of agricultural importance. The emerging pathogen D. solani may be a contributing factor to the increased incidence of blackleg and soft rot diseases on potato in Europe, whereas D. dianthicola, a close relative, is currently listed on the European and Mediterranean Plant Protection Organization’s list of pests recommended for regulation as quarantine pests. Presently, the North American Plant Protection Organization has placed D. solani on the U.S. list for emerging pest alerts. Symptoms caused by Dickeya spp. can be confused with those produced by Pectobacterium spp. in the field; differentiation of these two soft rot causing groups is time-consuming and requires multiple assays for confirmation. Therefore a robust rapid diagnostic test for the differentiation and detection of Dickeya spp. was developed using loop-mediated isothermal amplification (LAMP). In this study, a genus-specific LAMP assay was developed using whole genome data. The specificity of the assay was evaluated on six of the seven recognized Dickeya species and Pectobacterium spp. associated with potato; the LAMP assay only showed positive reactions with Dickeya spp. Direct detection of Dickeya from infected plant tissue was assessed and provided a result in less than 30 minutes. This LAMP assay offers a rapid and sensitive way for testing of Dickeya spp. from plant samples.