Detection of Polymorphism in Puccinia hordei using RFLP and RAPD Markers, Differential Cultivars, and Analysis of the Intergenic Spacer Region of rDNA

A world-wide range of isolates of Puccinia hordei atid P. striiformis f. sp. hordei and UK isolates of P. striiformis f. sp. iritici and P. recondita were characterized using DNA restriction fragment length polymorphisms (RFLPs), random amplified polymorphic DNAs (RAPDs), ribosomal DNA (rDNA) intergenic sequence (!GS) or virulence on differential cultivars. The different species were readily distinguished by both RFLPs and RAPDs. Within a species, variability was detected using differential cultivars, RAPDs, and RFLPs with probes from the rDNA region, indicating their potential for population analysis. However, RFLPs within a species were not detected using a wide range of random (anonymous) probes from a P. hordei genomic library. Previous assumptions about the general uniformity of rust genotypes were reassessed from these data.