umbellularia californica/agar

Extensive mortality of redbay (Persea borbonia (L.) Spreng.) has been observed in the southeastern United States since 2003. The mortality is due to laurel wilt caused by Raffaelea lauricola T. C. Harr., Fraedrich & Aghayeva, a fungal symbiont of the recently introduced redbay ambrosia beetle

Between 2001 and 2007, samples from three California native plants showing canker symptoms were submitted to the California Department of Food and Agriculture's Plant Pest Diagnostics laboratory. Giant sequoia (Sequoiadendron giganteum) and coast redwood (Sequoia sempervirens) showed branch cankers

In May 2005, branches originating from five separate whorls below the terminal on a single California red fir (Abies magnifica) in a mixed grand fir (Abies grandis) and Douglas-fir (Pseudotsuga menziesii) Christmas tree plantation near Los Gatos, CA displayed wilting and dieback of new shoot growth.

In May 2003, Phytophthora ramorum S. Werres & A.W.A.M. de Cock was isolated from the leaf tips of a single plant of false Solomon's seal (Maianthemum racemosum (L.) Link, formely known as Smilacina racemosa (L.) Desf.), a native, herbaceous perennial of the Liliaceae family, at the Jack London

During July 2005, Phytophthora ramorum S. Werres & A.W.A.M. de Cock was isolated from nine native Adiantum jordanii plants growing at two forest sites (Samuel P. Taylor State Park, Marin County and Peachland Road, Mendocino County) and from seven A. aleuticum plants at one forest site (Peachland

In May 2003, Phytophthora ramorum S. Werres & A.W.A.M. de Cock was isolated from leaflets of wood rose (Rosa gymnocarpa Nutt.), a native, low shrub of the Rosaceae family, at the Jack London State Park in Sonoma County, California. Affected leaflets had cream-to-brown lesions or spots, sometimes

Brisbane box,Lophostemon confertus (Myrtaceae) is a frost tender evergreen tree planted for its upright form, large ovate leaves and attractive white flowers which bloom in the spring. In June of 2017, the Plant Pest Diagnostics Center lab received a call from an arborist who described

In March 2002, Phytophthora ramorum S. Werres & A.W.A.M. de Cock was isolated from pacific or western starflower (Trientalis latifolia Hook.), an herbaceous perennial of the Primulaceae family, at Castro Canyon in Big Sur, Monterey County, California. Affected leaves had numerous necrotic

Although most Phytophthora species have a soilborne phase that is crucial for infection of roots and for survival away from the host, the details of the soil phase of Phytophthora ramorum are not yet fully understood. As mycelium ages, it becomes resistant to sterilization by acidic electrolyzed

OBJECTIVE To determine the effects of heat and composting treatments on the viability of the plant pathogen Phytophthora ramorum grown on both artificial and various natural substrates. RESULTS Phytophthora ramorum was grown on V8 agar, inoculated on bay laurel leaves (Umbellularia californica) and