RESISTANCE TO STRIPE RUST AND EYESPOT DISEASES OF WHEAT IN TRITICUM-TAUSCHII

A collection of 279 Triticum tauschii (syn. Aegilops squarrosa) accessions was evaluated for resistance to stripe rust (Puccinia striiformis) and eyespot (Pseudocercosporella herpotrichoides) diseases. Seedlings were inoculated with four different races of P. striiformis that represent all known virulences in the Pacific Northwest, and a genetically modified strain of P. herpotrichoides expressing beta-glucuronidase. Seventeen percent (44) of the T. tauschii accessions were resistant to all Pacific Northwest races of stripe rust, and 45% (115) were resistant to eyespot. Thirty-nine of the 279 accessions were resistant to the stripe rust races and the eyespot pathogen. Accessions resistant to stripe rust were mainly from the Caspian Sea region of Iran and Azerbaijan, with the majority belonging to T. rauschii subsp. strangulata and T. t. subsp. meyeri. There was no clear association between resistance to eyespot and geographical origin or taxonomic subgroup.