Development of a Micropropagation Protocol for the Ex Situ Conservation of Nuttall's Scrub Oak ().

Worldwide, oak species are threatened with extinction due to habitat loss, pathogens, and changing fire regimes. Ex situ conservation through tissue culture may protect the remaining genetic diversity of , or the coastal sage scrub oak, from further loss. We designed three basal salt formulations based on the mineral composition of shoot tips and first leaves from mature and explored carbohydrate source, stress-mitigating compounds, and plant growth regulator concentrations to develop a method of cultivating many culture lines in vitro.

Plant Cryopreservation: Principles, Applications, and Challenges of Banking Plant Diversity at Ultralow Temperatures.

Progressive loss of plant diversity requires the protection of wild and agri-/horticultural species. For species whose seeds are extremely short-lived, or rarely or never produce seeds, or whose genetic makeup must be preserved, cryopreservation offers the only possibility for long-term conservation. At temperatures below freezing, most vegetative plant tissues suffer severe damage from ice crystal formation and require protection.

Harnessing the power of botanical gardens: Evaluating the costs and resources needed for exceptional plant conservation.

Premise: The effective ex situ conservation of exceptional plants, whether in living collections or cryo-collections, requires more resources than the conservation of other species. Because of their expertise with rare plants, botanical gardens are well positioned to lead this effort, but a well-developed strategy requires a clear understanding of the resources needed.

Methods: Grant funding was obtained from the Institute of Museum and Library Services to support a three-year project on cryobanking, and to provide smaller grants to 10 other botanical gardens for one-year projects on either (1) seed behavior studies or (2) the development of protocols for in vitro propagation or cryopreservation.

Improving culture initiation of mature oak shoots through use of silver thiosulfate.

Premise: Of the approximately 430 species of oaks ( spp.) that have been assessed, 31% are threatened with extinction and in need of safeguarding. However, oak seeds cannot be seed banked, and thus rely on alternative strategies such as in vitro culture for ex situ conservation.

The Tip of the Iceberg: Cryopreservation Needs for Meeting the Challenge of Exceptional Plant Conservation.

Cryopreservation is increasingly important as a conservation tool, particularly for threatened exceptional species. The goal of this study was to investigate the current knowledge of plant cryopreservation through a search of the literature in Web of Science and align that with the 775 species currently identified on the Working List of Exceptional Plants. While there is a good foundation in plant cryopreservation research, particularly with economically important species, there are significant gaps in research on families that contain the largest numbers of currently known exceptional species, including the Dipterocarpaceae, Rhizophoraceae, and Pittosporaceae.

Survival and growth of embryo axes of temperate trees after two decades of cryo-storage.

Liquid nitrogen (LN) storage is recommended for conserving plants with seeds for which standard seed banking is not feasible, but there are few empirical reports confirming its long-term effectiveness. In this study we evaluated in vitro viability and ex vitro growth of embryo axes of a species that is short-lived in seed bank conditions (Juglans nigra) and two recalcitrant seeded species (Aesculus hippocastanum and A. glabra) that were stored 11-23 years in LN.

Tools for the conservation of the threatened species, var. .

conservation is critical for hedging against the loss of plant diversity. For those species (exceptional species) that cannot be conserved long-term in standard seed banks, alternative methods are required, often involving culture and cryopreservation, or storage in liquid nitrogen. var.

Differential effects of abscisic acid on desiccation tolerance and carbohydrates in three species of liverworts.

Tissues of three species of in vitro grown liverworts, Riccia fluitans, Pallavicinia lyellii, and Marchantia polymorpha, were subjected to rapid drying with and without preculture for 1 week on medium containing 10 microM ABA. ABA preculture initiated total desiccation tolerance in R. fluitans, whereas control tissues were killed after 30 min of drying.