Introduction to our ‘Guest Blog’ below (by Shelagh McCartan)
Forests and woodlands are increasingly under threat from overexploitation, habitat destruction, climate change, and pests and pathogens. Consequently, there are many efforts to preserve seeds in seed banks worldwide. I asked Katherine O’Donnell for background information about the ‘Global Seed Conservation Challenge’, which she is co-ordinating for Botanic Gardens Conservation International.
Guest Blog by Katherine O’Donnell (Global Seed Conservation Challenge Coordinator, BGCI, UK)
Given the array of ex situ conservation techniques currently available (seed banking, cultivation, tissue culture etc.) there is no technological reason why any plant species should go extinct. Of these various techniques, seed banking is by far the most efficient and effective. By storing seed in seed banks a species is safeguarded from extinction and a source of seed is available when required. Orthodox seeds can be collected from plants, dried and stored in cool conditions for decades and sometimes even centuries until they are required for research, restoration or reintroduction. With 1 in 5 plant species estimated to be at risk of extinction, seed banking is a vital component of plant conservation.
Botanic gardens are the main institutions involved in ex situ conservation of threatened species with one third of wild plant species found in botanic garden collections. Botanic gardens have the expertise to save wild species from extinction. This involves collection in the field, to taxonomic identification in herbaria, research in laboratories, propagation in nurseries and ultimately restoration and reintroduction in the wild. Over 400 botanic gardens around the world maintain effective seed banks for wild plant species, contributing to long term storage of plant diversity. These seed banks store seed from more than 5,000 tree species. Threatened species include the wild relatives of coffee (Coffea macrocarpa and Coffea myrtifolia), mahogony (Swietenia mahagoni) and several species of hibiscus (Hibiscus clayi, Hibiscus scottii, Hibiscus taiwanensis).
Botanic Gardens Conservation International (BGCI) has recently launched the Global Seed Conservation Challenge. This initiative will encourage botanic gardens to work ‘outside the garden walls’ to collect and bank seed of threatened species towards Target 8 of the Global Strategy for Plant Conservation (a program of the UN’s Convention on Biological Diversity). This target calls for ‘at least 75% of threatened species to be in ex situ collections by 2020’. Various prizes will be awarded at BGCI’s next Global Botanic Garden Congress to institutions that, for example, conserve the greatest number of taxa or conserve the most threatened species.
At BGCI we are building the most comprehensive list of tree species in the world. TreeSearch, which is due to be launched next year, currently contains around 70,000 species of which more than 9,000 are known to be threatened with extinction. This data will enable botanic gardens to prioritise banking of species most at risk of extinction, focusing efforts on those that are not already in ex situ collections.
Erythrina sandwicensis seeds cleaned and ready for storage (Tien Austin)