In-Vitro Propagation and Conservation of Five Imperiled Southeastern U.S. Oak Species

Qiansheng Li, Oliver Hutchens, Lauren Eserman, Jason Ligon, Laurie Blackmore, and Emily E.D. Coffey

Published May 2026 in International Oaks No. 37: 347–356

Abstract

Ex-situ conservation is crucial to prevent the extinction of declining keystone oak (Quercus) species threatened by human disturbance, climate change, pests, and pathogens. Because the recalcitrant seed biology of oaks limits conventional dry-seed storage, tissue culture is a vital alternative ex-situ conservation tool, complementing living collections with in-vitro propagation and conservation for endangered oak species. The Atlanta Botanical Garden’s Southeastern Center for Conservation has developed in-vitro conservation protocols for five imperiled oak species native to the Southeastern United States: Quercus acerifolia (EN), Q. arkansana (VU), Q. boyntonii (CR), Q. georgiana (EN), and Q. oglethorpensis (EN). In-vitro propagation protocols were developed from nodal or seed explants; the multiplication and rooting media were optimized with woody plant media supplemented with different concentrations of BA and IBA. In-vitro plantlets that successfully rooted are acclimatized in the greenhouse and can then be grown out as part of the Garden’s Quercus metacollection. Somatic embryogenesis is achieved by using the in-vitro shoot tips and leaves. The somatic embryos and in-vitro shoot tips are ideal materials for cryopreservation, via vitrification or encapsulation, to establish long-term conservation strategies for these and other endangered oak species.

Keywords

micropropagation, somatic embryogenesis, Quercus

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