However, new exotic pests also threaten the chestnut. Blight-resistant hybrids have already proven susceptible to Phytophthora cinnamomi, or root rot, which preys upon tree roots in mostly wet, southern soils.
"This threatens to be almost as bad as the fungal blight," Jacobs said. "In the future, we may need to select for this resistance in new hybrids. Luckily, the Asian chestnut shows some resistance to this fungus as well, although the breeding process would take a long time."
Jacobs said the tree could be ecologically less desirable in some areas.
"It's a natural choice for hardwood plantations in the Midwest and Mississippi Valley, but these areas are largely outside its native range," he said.
The chestnut could threaten native species outside its range since it is competitive and quick-growing, he said.
If individuals or groups decided not to accept the hybrid American chestnut as a native species, and this in turn impeded its reintroduction, it would likely encourage more research into ways to genetically engineer the tree, especially since it has potential as a profitable species, Jacobs said.
"This would likely be less acceptable to those who would think twice about reintroducing a hybrid of a native tree, and it would be difficult to prevent without a better alternative," he said.
| Contact: Douglas M. Main dmain@purdue.edu 765-496-2050 Purdue University Source:Eurekalert |