Differentiation of Poaceae Potyviruses by Reverse Transcription-Polymerase Chain Reaction and Restriction Analysis

Four potyviruses have been reported to infect Poaceae] maize dwarf mosaic virus "MDMV#\ sugarcane mosaic virus "SCMV#\ johnsongrass mosaic virus "JGMV# and sorghum mosaic virus "SrMV#[ A procedure was developed to assess the potential presence of potyviruses in a Poaceae!infected sample\ and then to determine which potyvirus species "one or more# were present[ The _rst step was potyvirus!group speci_c and following total RNA extraction\ reverse transcription and polymerase chain reaction\ it yielded a 216 nucleotide fragment span! ning MVWCIEN to QMKAAA conserved motifs in the core of the capside gene[ Enzymatic restriction of this fragment with the two endonucleases AluI and DdeI gave virus!speci_c patterns[ This method was shown to be e.cient for dealing with well!characterized strains and _eld collected isolates and useful for determining co! infections and detecting a new potyvirus infecting maize