Oral: Shovel-Ready Trees: Novel Strategies for Development of Disease Resistant Woody Plants
Rapid selection and opportunities for restoration of laurel wilt tolerant Persea species.
J. SMITH (1), M. Hughes (2), B. Held (3), R. Blanchette (3), T. Dreaden (4), R. Ploetz (2) (1) University of Florida, U.S.A.; (2) University of Florida, U.S.A.; (3) University of Minnesota, U.S.A.; (4) USDA-Forest Service, Southern Research Station, U.S.A
In little more than a decade, laurel wilt caused by Raffaelea lauricola (vectored by Xyleborus glabratus) has spread to nine U.S. states, killing hundreds of millions of redbay (Persea borbonia) trees, altering ecosystems and threatening worldwide avocado production. Typically, ambrosia beetles and their fungal symbionts are not tree killers. LW is unique in that the symbiont of X. glabratus is highly virulent to host trees. Current efforts to manage LW focus on systemic fungicides, insect repellents, sanitation. Naturally occurring forests with high mortality (> 95%) form LW have been explored for persistent survivor trees. Propagation and subsequent disease screening have been carried out leading to the identification of disease tolerant redbay clones. Mechanisms of tolerance appear to be associated with reduced tylosis and reduced disruption of vascular function. Seedling populations from tolerant clones have been genotyped and are being phenotyped for tolerance to assist restoration efforts. Future research will focus on genomic analyses as well as examinations of how phylogeography influences host susceptibility within the Lauraceae.