International efforts to save some of the world’s rarest and economically important plants from climate change are doomed to fail because their seeds cannot be stored, researchers warned Friday.
As the planet heats and mankind continues to decimate natural habitats, scientists concede that the only way to save some types of vegetation is in seed banks — giant repositories of thousands of species preserved for future generations.
Nations agreed a global strategy in 2002 to conserve at least three quarters of threatened plant species with the aim of recovering and restoring their stocks in nature at some point.
Scientists working in several seed banks around the world currently conserve seeds by drying them before freezing.
But new research by botanists at Britain’s Royal Botanic Gardens, Kew, found that 36 percent of “critically endangered” plants and trees aren’t bankable under the current method because their seeds die when dried and so cannot be preserved by freezing.
“You can’t dry the seeds so you cannot conserve them in a conventional seed bank,” John Dickie, head of collections at Kew, told AFP.
It was previously known that at least eight percent of plants — including oak trees, mango, avocado and cacao — produce “recalcitrant” seeds that die when dried.
But with seed banking a work in progress, only a small proportion of plants have had their suitability for freezing assessed.
Dickie and his team developed a model using data on the climate, species habitat and the known seed-storage behaviour of related vegetation that predicted how likely it was that a plant’s seeds would be bankable.