Authors
James H.
Lorenzen
,
PSES Department, University of Idaho, Moscow 83844
;
Lisa M.
Piche
and
Neil C.
Gudmestad
,
Department of Plant Pathology, North Dakota State University, Fargo 58105
; and
Teresa
Meacham
and
Pat
Shiel
,
PSES Department, University of Idaho, Moscow 83844
ABSTRACT
Potato virus Y (PVY) has become a serious problem for the seed potato industry, with increased incidence and rejection of seed lots submitted for certification. New PVY strains and strain variants have emerged in recent decades in Europe and North America, including the PVYN strain that causes veinal necrosis in tobacco, and strain variants that represent one or three recombination events between the common strain (PVYO) and PVYN. Several reverse transcription-polymerase chain reaction (RT-PCR) assays have been described that characterize PVY isolates as to strain type, but they are limited in their ability to detect some combinations of mixed strain infections. We report here the development of a single multiplex RT-PCR assay that can assign PVY strain type and detect mixed infections with respect to the major strain types. Validation of this assay was achieved using 119 archived PVY isolates, which had been previously characterized by serology and bioassay and/or previously published RT-PCR assays. Results for single-strain isolates were comparable to previous results in most cases. Interestingly, 16 mixed infections were distinguished that had previously gone undetected. The new multiplex RT-PCR assay will be useful for researchers and seed production specialists interested in determining PVY infection type using a single assay.
