Evaluation of Dasypyrum villosum populations for resistance to cereal eyespot and stripe rust pathogens

Resistance to Pseudocercosporella herpotrichoides (cause of eyespot) and Pu ccinia striiformis (cause of stripe rust) was evaluated in a germ plasm col lection of Dasypyrum villosum (syn. Haynaldia villosa) and a set of disomic addition lines, a substitution, and a translocation line of D. villosum ch romosomes in a wheat background. Three races of P. striiformis and a beta-g lucuronidase-transformed strain of Pseudocercosporella herpotrichoides were used to inoculate plants and evaluate disease reactions. Of the 115 D. vil losum accessions tested, 33 (28.6%) were resistant to one or more races of Puccinia striiformis and 8 accessions were resistant to all races. All 219 accessions of D. villosum tested were resistant to Pseudocercosporella herp otrichoides and 158 (72%) of the accessions had lower beta-glucuronidase ac tivity than the resistant wheat line VPM-1. Most of the accessions of D. vi llosum resistant to the stripe rust pathogen originated from Greece; howeve r, there was no distinction among origins for resistance to the eyespot pat hogen. Chromosome 4V was confirmed to carry the gene for resistance to P, h erpotrichoides. At least one gene for resistance to Puccinia striiformis wa s located on the short arm of chromosome 6V of D. villosum in the 6VS/6AL-t ranslocation line; this gene was named Yr26.