Seed banks are the last hope for endangered plants, but these flower vaults can not save some of the most iconic and endangered species.
More than a third of endangered plant species can not be preserved in seed banks with current methods, researchers have discovered.
Seed banks dry and freeze to -20 ° C (-4 ° F) to preserve valuable items to save plants, trees, and wild relatives of crops.
Important British tree species such as oak, horses and chestnuts as well as global foods such as avocado and cocoa could be lost forever if current methods are not updated.
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Vault at the Millennium Seed Bank in Wakehurst (pictured) is one of the latest hopes for endangered plant species. Researchers have warned that more than a third of endangered plant species can not be kept in seed banks to save them from extinction
A global crop protection strategy has set itself the target of conserving 75% of endangered species outside their natural habitat – or "ex-situ" – by 2020.
Places like the Millennium Seed Bank of Kew on Wakehurst Place, West Sussex and the Global Seed Vault of Svalbard are trying to meet these criteria.
Saatbanking in the traditional sense will not work for many endangered plants. Researchers call for urgent investment and research to create alternatives to preserve some of the world's most threatened assets.
According to a study by researchers at the Royal Botanic Gardens, Kew, last year about 8 percent of all plants in the world produce seed that can not be brought into the bank.
Research by Kew's team indicates that the problem may be worse for endangered species.
Researchers used four large plant lists and examined different categories of endangered plants to determine how many species are likely to be "bankable".
They estimate that 36 percent of the most endangered species or critically endangered species produce "unruly seed".
This means that they can not survive the drying process and can not be frozen, making them "unbankable," according to the study published in the journal Nature Plants.
The seed banks are dried and then deep-frozen to -20 ° C to preserve the seeds. In an effort to preserve plants, trees and wild relatives of crops. Important British tree species such as oak and horse chestnuts could be lost forever if current methods are not updated
More than a quarter (27 percent) of the endangered species produce seeds that can no longer be used, along with 35 percent of the plants that are considered endangered.
It's a special problem for trees. 33 percent of all tree species in the world produce seeds that do not survive the drying process, according to the study.
In tropical wetlands, such as rainforests or cloud forests, half of the tree species that make up the roof may be unsuitable for conservation in seed banks.
An alternative to conventional storage in seed banks could be "cryopreservation".
In doing so, the embryo is removed from the seed and frozen with liquid nitrogen to -196 ° C (-320 ° F), thereby preserving "non-bankable" seeds.
HOW IS A SEED INTO A COMPLETE PLANT?
Most plants grow from seeds, which are available in different shapes and sizes.
This compact package contains everything the plant needs to grow and multiply.
The outer shell of the seeds is called fur, which protects the baby plant, and is split when it begins to grow.
In order for plants to become seeds, they need soils that contain nutrients, water, sunlight, proper temperature, room to grow, and time.
In order for plants to become seeds, they need soils that contain nutrients, water, sunlight, proper temperature, room to grow, and time. When the conditions are just right, the seed sprouts roots deep into the ground to collect water
When the conditions are just right, the seed begins to sprout roots deep into the ground to collect water while a log shoots up.
The plant knows how its roots and stems can grow, as it can sense the gravitational attraction of the soil. As the stalk is grown in the opposite direction, the roots of gravity are aligned accordingly.
As soon as the stem has broken through the soil surface, leaves grow to collect sunlight.
The plant has specialized cell machines, ie the trunk always grows towards the sun to make sure it is pointing in the right direction.
John Dickie of the Millennium Seed Bank of Kew and one of the newspaper's authors said: "Ex-situ conservation of plants is more important than ever, as many threats to plant populations such as climate change, habitat conversion and plant pathogens are needed to ensure that we Do everything possible to preserve the most important and endangered species.
"As successful seed banks are for some species, it is not suitable for all seed crops, and we need to invest in other ways to protect unruly seed.
"This paper shows that we need greater international efforts to understand and apply alternative techniques such as cryopreservation that have the potential to prevent many more species from extinction."
Conventional seed banks for game species should demonstrate their strengths as they seek to conserve species such as medicinal plants and wild-growing relatives.
The researchers also warn that it is "somewhat naïve and dangerous" to assume that conservation outside of habitats is a valid way to protect a high proportion of tropical, damp forest trees from extinction – and preserve the forest be the only one possible for many plants.