Submitted to: National American Phytopathology Meetings
Publication Type: Abstract Only
Publication Acceptance Date: October 1, 2003
Publication Date: December 15, 2003
Citation: Larkin, R.P., Groves, C.L. 2003. Identification and characterization of isolates of phytophthora infestans using fatty acid methyl ester (fame) profiles. Plant Disease 87:1233-1243 Technical Abstract: The utility of fatty acid profiles for characterization and differentiation of isolates of P. infestans was investigated. A library of FAME profiles was established from at least 8 replicate sample runs of each of 25 different isolates of P. infestans, including representative isolates of US-1, US-6, US-7, US-8, US-11, US-14, and US-17 genotypes. This library wa then used to characterize additional unknown isolates. Fatty acids were extracted from cultures grown on pea broth agar using the MIDI system (MIDI, Inc., Newark, DE) protocols and identified using a gas chromatograph and MIDI peak naming software. FAME profiles from P. infestans were consistent over multiple extraction runs and distinctly different from profiles of other Phytophthora species, such as P. capsici and P. erythroseptica, as well as Pythium spp. and all fungal groups tested. Profiles from different isolates of the same genotype tended to group together, although there was overlap among some genotypes. Profiles were specific enough that individual isolates could be distinctly identified by their FAME profiles. In general, individual isolate characteristics were more determinant than genotype group characteristics, although genotype could be determined for most isolates tested. Results indicated that FAME profiles can be an additional tool useful for characterizing isolates and populations of P. infestans.