Evidence for the role of synchronicity between host phenology and pathogen activity in the distribution of sudden oak death canker disease.
Variations in synchronicity between colonization rate by the pathogen and host phenology may account for unexplained spatial distribution of canker disease. The hypothesis that synchronous pathogenicity and host development are necessary for incidence of sudden oak death disease was tested by correlating seasonal variations in host cambial phenology and response to inoculation with Phytophthora ramorum. Response to infection was estimated by inoculating branch cuttings from coast live oak (Quercus agrifolia) trees at nine dates through a full annual cycle in 2003-2004. Host phenology was estimated from measurements of bud burst and cambial activity in spring 2006. Lesions were largest in the spring soon after the cambium resumed activity. A moderate genetic component to lesion size was detected. Variation among trees in date of largest lesions correlated with variation in timing of bud burst and cambial phenology. The data support the hypothesis that active host cambial tissue is a necessary requisite for successful infection with the pathogen that causes sudden oak death canker disease. Genetic variation in host phenology will buffer coast live oak against epidemics of this disease.
Dodd
Richard S
RS
Department of Environmental Science Policy and Management, 137 Mulford Hall, University of California, Berkeley, CA 94720, USA.
Hüberli
Daniel
D
Centre for Phytophthora Science and Management, School of Biological Sciences and Biotechnology, Murdoch University, Murdoch, WA 6150, Australia.
Mayer
Wasima
W
Department of Environmental Science Policy and Management, 137 Mulford Hall, University of California, Berkeley, CA 94720, USA.
Harnik
Tamar Y
TY
Department of Environmental Science Policy and Management, 137 Mulford Hall, University of California, Berkeley, CA 94720, USA.
Afzal-Rafii
Zara
Z
Department of Environmental Science Policy and Management, 137 Mulford Hall, University of California, Berkeley, CA 94720, USA.
Garbelotto
Matteo
M
Department of Environmental Science Policy and Management, 137 Mulford Hall, University of California, Berkeley, CA 94720, USA.
D010838:Phytophthora / Q000502:physiology*; D010935:Plant Diseases / Q000382:microbiology*; D029963:Quercus / Q000382:microbiology*; D012621:Seasons; D013997:Time Factors