Rescue of American chestnut with extraspecific genes following its destruction by a naturalized pathogen
Steiner, K.C., Westbrook, J.W., Hebard, F.V. et al. New Forests (2017) 48: 317. doi:10.1007/s11056-016-9561-5
There are several efforts underway to restore the American chestnut involving traditional breeding methods, simple conservation strategies, methods that would reduce the virulence of the blight fungus, as well as modern gene-transformation techniques. The American Chestnut Foundation (TACF) is involved with each method, but focuses primarily on classical breeding techniques.
Some methods being explored toward American chestnut restoration are:
AT THE INTERFACE OF CLASSICAL BREEDING AND BIOTECHNOLOGY
Backcross breeding and transgenic/cisgenic technology are two potentially complementary strategies to introduce genetic resistance to blight into American chestnut. Read more.
While the broadest goal of TACF is to restore the American chestnut species, the organization focuses on two major objectives: (1) introducing the genetic material responsible for the blight resistance of the Chinese tree into the American chestnut; and (2) preserving the genetic heritage of the American chestnut species by planting and grafting native germplasm before it disappears.
Each chestnut species – of which there are about seven – varies with regard to blight-resistance. Blighted North American chestnut species usually die, while blighted Asiatic chestnuts typically suffer only cosmetic damage. With that in mind, Chinese and Japanese chestnuts offer a potential solution to the American tree’s susceptibility to chestnut blight through hybridization