Sudden oak death, caused by the pathogen Phythophthora ramorumis one of the most ecologically devastating forest diseases in North America, responsible for the death of millions of oaks and tanoaks along the coast.
Science to the rescue? Following the success of genetically modified organisms in things like insulin and food, a recent trend is genetically rescued organisms. These GROs would use science to create natural resistance, like a vaccine for plants, and reduce the impact of altered species composition, freed carbon pools and greater fire risk the deaths bring.
Before that can happen, scientists need to better understand the basic biology Phythophthora ramorumincluding how well it sporulates on common plants.
Image by RegalShave from Pixabay
Researchers at the University of California, Davis, attempted to investigate the sporulation potential of this pathogen on common plant species in California. They collected leaves from 13 common plant hosts in the Big Sur region and inoculated them with the causal pathogen. They found that most of the species produced spores, although it was an equestrian area, with laurel and tanoak producing significantly more sporangia than the other species. They also observed an inconsistent relationship between sporulation and lesion size, indicating that visual symptoms are not a reliable metric of sporulation potential.
“Our study is the first to examine the sporulation capacity of a wide range of common coastal native plant species in California and with a large enough sample size to statistically distinguish between species,” explained first author Dr. Lisa Rosenthal. “It largely confirms what was previously reported in observational field studies—that tanoak and laurel are the main drivers of sudden oak death infections—but also indicates that many other hosts are capable of producing spores.”
Citation: Lisa M. Rosenthal, Sebastian N. Fajardo, and David M. Rizzo, Sporulation Potential of Phytophthora ramorum Distinct among common plant species in California in the Big Sur region, Plant Disease August 17, 2021 https://doi.org/10.1094/PDIS-03-20-0485-RE
