PhD Oral Defence of Christie-Anna Lovat, Plant Science
American chestnut (Castanea dentata (Marsh.) Borkh.) is functionally extinct in its native range. Short term conservation methods for C. dentata in tissue culture were developed and improved upon in this work. Methods to improve multiplication rate (physiological stage of source material and incubation temperature) and microshoot quality (effect of exogenous medium modifications in 6-benzylaminopurine, calcium, magnesium, boron, and gelling agent type and concentration on the incidence of shoot top necrosis (STN)) were investigated in the axillary shoot culture of genotypes from genetically diverse sub-populations of C. dentata. Physiological stage of source material effected multiplication rate, with seedling-stage source material producing the most vigorous cultures. Incubation temperature effected multiplication rate in three out of eight genotypes tested.