Seed banks provide hope for endangered planet
Preserving plant seeds and other genetic material warrants investment of hundreds of millions of dollars, as it provides a lifeline for the future, scientists say.
“If the world ends one day, these collections will bring hope of a new beginning to life on Earth,” said Li Pei, a staff member at the Germplasm Bank of Wild Species, or GBOWS, in Yunnan province.
The rapid loss of biodiversity and germplasm resources is the main reason for the establishment of seed banks. There are now more than 1,750 such banks globally, according to the United Nations Food and Agriculture Organization.
“For the preservation of biodiversity, such banks are crucial,” Li said. “The more collections we have, the greater the chance of saving plants and animals, especially those that are critically endangered.”
GBOWS, founded in 2007, is a research and preservation facility for rare and endangered plants and animals. It is the
only comprehensive institution of its kind for storing wild plant and animal germplasm resources in China and is the largest in Asia in terms of species, Li said.
Affiliated to the Kunming Institute of Botany, which is responsible to the Chinese Academy of Sciences, GBOWS comprises a seed bank, a micropropagation unit, a plant DNA bank, a microbial bank based at Yunnan University, and an animal germplasm bank at the Kunming Institute of Zoology. It also boasts experimental research laboratories for plant genomics and seed biology.
GBOWS has preserved 85,046 seed accessions from 10,601 species, 24,100 tissue samples from 2,093 species, 65,456 extracted samples of DNA material from 7,324 species, 22,800 strains of 2,280 microorganisms, and 60,262 biological samples of 2,203 wild animal species and domestic animal breeds.
Yu Fuqiang, deputy director of the germplasm bank, said, “The bank functions as a bio dome that protects wild organisms, especially those endangered species or species with high economic and scientific value, from extinction.”
In China, areas rich in biodiversity range from the dry northwest, even though it is surrounded by huge mountain ranges on the QinghaiTibet Plateau, to the tropical and subtropical south. The remote mountainous areas and diverse microclimates have resulted in high levels of endemism, the condition of being endemic, or restricted in geographical distribution to an area or region.
The seed bank has preserved 85,046 accessions of 10,601 species, accounting for 36% of the seed plants in China, Li said.
With two in five plant species at risk of extinction, she said, it is a race against time to protect the country’s incredible plant life.
“Wild species germplasm has great application potential in the biological sphere, especially for the collection and preservation of wild plants,” Li said.
“We store seeds that are collected in the wild so that we can germinate and reintroduce these plants to the wild or use them for scientific research in finding our future food and medicines, and for other functions.”
For example, the seeds of Silene stenophylla, a plant species in the carpetweeds family, can maintain their viability for up to 32,000 years.
Collecting seeds is the first step of preservation, and GBOWS works on this with national partners who receive regular training from the seed bank.
Apart from seeds, collectors take specimens for verification. For future study, they record details of the plant, including where it was found, its size and the number of individual plants in the habitat.
This year collectors from the bank visited many regions nationwide, including areas with low populations in western China and also sinkholes in the south and southwest.
After arriving at the bank the seeds undergo a series of processes before they can be stored long-term.
First they are checked by botanists to ensure their identity. Then the seeds are slowly dried to 5% moisture content in a drying chamber, which maintains a temperature of 15 C (59 F) and relative humidity of 15%.
The seeds are next cleaned before being weighed and counted manually, which is time-consuming and requires patience and an eye for detail.
Then the seeds are placed in suitable containers and weighed on an electronic scale under a plastic cover, which prevents the results being influenced by factors such as the wind.
The weight of the seeds is recorded in grams correct to four decimal places, even more accurate than a scale for weighing gold.
Before being stored, the seeds undergo an X-ray quality check. After this they are photographed.
Li Lianyi, a seed morphology researcher, said: “For big seeds an ordinary camera is enough, but for those with a diameter of 0.04 or 0.08 inches, photomicrography is used. Some tiny seeds cannot be seen by the naked eye, but photomicrography allows us to appreciate their spectacular shapes and colors.”
After these procedures are completed, the seeds are sealed in glass bottles or jars. Each container has a barcode that can be scanned to enable scientists to view information about the seeds inside.
The containers, large and small, are stored in a huge chamber at minus 20 C. Such chambers are freezers built underground to reduce the influence of the environment.
The seed bank has five such chambers, covering a total of 2,045 square feet and capable of storing 170,000 collections.
Germination tests are conducted on a seed accession after it is banked to ascertain viability and to establish a germination protocol.
Seed revival is conducted on a palm-sized cell culture dish with agar, a gelatinous substance obtained from some red seaweeds. In most cases it usually takes a few days for the seeds to sprout.
Li Hui, a seed curator, said, “Some seeds remain dormant and need a little inducement to wake them up, for example, a biological enzyme or an external force, such as chipping or breaking out the hard seed coating.”
For seeds without a germination study, Li Hui said, it sometimes takes four or five years for them to revive.
The bank has provided technical support for the preservation, research and use of China’s wild plants. It also provides seed germination guidance services.
“Most of the orders are from forestry, grassland and agricultural colleges and research institutes,” Li Hui said.
“A test is usually conducted every five or 10 years after the seeds are stored to check their ability to grow. The result is a significant part of our research on the plant.”
In addition to working with 105 research institutes and preservation centers nationwide, the seed bank works with international partners, including Kew Gardens in England, on collecting backup specimens, exchanges and research.
Li Pei, the staff member, said, “Duplication storage is widely used in case the seeds are destroyed in natural disasters, other accidents or in wars.”
Wild plant protection is recognized globally as a crucial method of biodiversity conservation, because wild species have significant survival potential, she said.
GBOWS has also puts considerable effort into studying DNA study and preserving wildlife, she said, citing as an example protection of the Chinese yew, which is critically endangered and under toplevel national preservation.