文档介绍：The Plant Cell, Vol. 10, 947–956, June 1998, © 1998 American Society of Plant Physiologists
An Arabidopsis Mutant with Enhanced Resistance to
Powdery Mildew
Catherine A. Frye and Roger W. Innes1
Department of Biology, Indiana University, Bloomington, Indiana 47405
We have identified an Arabidopsis mutant that displays enhanced disease resistance to the fungus Erysiphe cichora-
cearum, causal agent of powdery mildew. The edr1 mutant does not constitutively express the pathogenesis-related
genes PR-1, BGL2, or PR-5 and thus differs from previously described disease-resistant mutants of Arabidopsis. E.
cichoracearum conidia (asexual spores) germinated normally and formed extensive hyphae on edr1 plants, indicating
that the initial stages of infection were not inhibited. Production of conidiophores on edr1 plants, however, was Ͻ16%
of that observed on wild-type Arabidopsis. Reduction in sporulation correlated with a more rapid induction of defense
responses. pounds and callose accumulated in edr1 leaves 3 days after inoculation with E. cicho-
racearum, and dead mesophyll cells accumulated in edr1 leaves starting 5 days after inoculation. Macroscopic patches
of dead cells appeared 6 days after inoculation. This resistance phenotype is similar to that conferred by “late-acting”
powdery mildew resistance genes of wheat and barley. The edr1 mutation is recessive and maps