First report of the NA2 clonal lineage of the sudden oak death pathogen, , infecting tanoak in Oregon forests.

Werres, de Cock & Man in't Veld, causal agent of sudden oak death (SOD) and ramorum leaf blight, is comprised of four clonal lineages in its invasive ranges of North America and Europe (Grünwald et al. 2012, Van Poucke et al. 2012).

Phylogeography of the wide-host range panglobal plant pathogen Phytophthora cinnamomi.

Various hypotheses have been proposed regarding the origin of the plant pathogen Phytophthora cinnamomi. P. cinnamomi is a devastating, highly invasive soilborne pathogen associated with epidemics of agricultural, horticultural and forest plantations and native ecosystems worldwide.

Soilborne and Diversity From Rhododendron in Propagation, Container, and Field Production Systems of the Pacific Northwest.

Rhododendron root rot is a severe disease that causes significant mortality in rhododendrons. Information is needed about the incidence and identity of soilborne and species causing root rot in Pacific Northwest nurseries in order to better understand the disease etiology and to optimize disease control strategies. The last survey focusing solely on soilborne oomycete pathogens in rhododendron production was conducted in 1974.

Population Structure of on in Oregon Nurseries.

is a recently described plant pathogen, formerly recognized as . Recent sampling of Pacific Northwest nurseries frequently encountered this pathogen, and it has been shown to be among the most damaging pathogens on ornamentals. We characterized the population structure of in a survey of four Oregon nurseries across three different counties with focus on hosts.

Pathogenicity, Fungicide Resistance, and Genetic Variability of Phytophthora rubi Isolates from Raspberry (Rubus idaeus) in the Western United States.

Root rot of raspberry (Rubus idaeus), thought to be primarily caused by Phytophthora rubi, is an economically important disease in the western United States. The objectives of this study were to determine which Phytophthora species are involved in root rot, examine the efficacy of different isolation methods (cane, root, and root/soil baiting with young raspberry plants), and determine if pathogenicity, fungicide resistance, and/or genetic variation exists among P. rubi isolates collected from raspberry fields in Washington, Oregon, and California.

The Irish potato famine pathogen Phytophthora infestans originated in central Mexico rather than the Andes.

Phytophthora infestans is a destructive plant pathogen best known for causing the disease that triggered the Irish potato famine and remains the most costly potato pathogen to manage worldwide. Identification of P. infestan's elusive center of origin is critical to understanding the mechanisms of repeated global emergence of this pathogen.

Phytophthora community structure analyses in Oregon nurseries inform systems approaches to disease management.

Nursery plants are important vectors for plant pathogens. Understanding what pathogens occur in nurseries in different production stages can be useful to the development of integrated systems approaches. Four horticultural nurseries in Oregon were sampled every 2 months for 4 years to determine the identity and community structure of Phytophthora spp.