On July 27, a group of chestnut researchers, Georgia and Tennessee Chapter members, and TACF staff convened at Berry College in Rome, Georgia. The purpose was to discuss southern germplasm conservation strategies, vegetative propagation of American chestnuts, and acceleration of flowering using light treatments. The group had a productive discussions over lunch and toured the Berry College backcross orchard in the afternoon, where Dr. Martin Cipollini’s students worked hard to prepare the orchard for the meeting. Dr. Cipollini is a GA Chapter board member and Dana Professor of Biology at the college.
One major challenge we face is incorporating genetic diversity from areas where chestnuts are not producing nuts. Historically, TACF has mostly depended on breeding with rare, flowering American chestnuts that are accessible by ladders and bucket trucks. This approach is the base of our breeding programs at Meadowview Research Farms and in our state chapters. TACF is working on testing other methods propagating American chestnut, such as grafting, rooted cuttings, stooling, and more, that do not depend on the tree being sexually mature and producing nuts.
Dr. Cipollini showed the group his small-scale stooling experiment just outside his office building. He cut an American chestnut dying of the blight and has treated the sprouts in an attempt to force rooting. This method is commonly used in the European chestnut cultivation business in Italy and other European countries. Other attendees, such as Dr. Hill Craddock and his graduate student at the University of Tennessee – Chattanooga, Trent Deason, plan to focus on grafting American chestnuts to capture new sources of germplasm.
The other major discussion point of the meeting was decreasing the time it takes for a tree to produce nuts. Being able to accelerate the production of flowers would allow us to decrease the period of time between generations when breeding. By capturing germplasm systematically and by speeding up the breeding, we could create a more genetically-diverse and locally-adapted population for American chestnut restoration in the forests across its native range.