Seed banks ‘cannot save all at-risk plants’

MORE THAN a third of critically endangered plant species cannot be preserved in seed banks to save them from extinction, researchers have warned.

Efforts to conserve plants, trees and wild relatives of crops outside their natural habitat mostly focus on storing seeds using a process of drying and then deep freezing them at minus 20C in seed banks.

A global strategy for plant conservation has set a target to conserve 75 per cent of threatened species outside their natural habitat – or “ex-situ” – by 2020, in places such as Kew’s Millennium Seed Bank at Wakehurst Place, West Sussex.

But for many of the at-risk plants, conventional “seed banking” will not work, prompting a need for urgent investment and research into alternatives to preserve some of the world’s most threatened plants, the researchers said. A study last year by researchers from the Royal Botanic Gardens, Kew, estimated that about eight per cent of all the world’s plants produce seeds which cannot be banked, including important UK tree species such as oak, horse and sweet chestnuts, and global foods including avocado and cocoa. Now new research from the team at Kew suggests the problem may be worse for species that are at risk of extinction. John Dickie, of the seed bank and one of the authors of the paper, said: “We need to make sure we’re doing all we can to conserve the most important species.”