Use of group-specific primers and the polymerase chain reaction for the detection and identification of luteoviruses.

A general diagnostic assay for a number of distinct luteoviruses was developed using the polymerase chain reaction (PCR) and restriction enzyme analysis. Two minimally degenerate, group-specific primers were derived from previously published RNA sequences of three luteoviruses. This primer pair generated specific PCR fragments of about 530 bp from extracts of plants infected with potato leafroll virus, beet western yellows virus, or New York barley yellow dwarf virus (BYDV) serotypes MAV, PAV, RMV, RPV and SGV, which span much of the respective viral coat protein gene. Each virus was easily distinguished from the others by restriction enzyme analysis of the amplified DNA products. Samples from BYDV-infected oat and wheat collected in Nebraska were identified as containing PAV-like serotypes; micro-heterogeneity was detected in several samples. This method provides a rapid, sensitive and relatively inexpensive means of luteovirus detection and identification. It is the first test capable of simultaneously detecting all five BYDV serotypes.