Build a Noah’s Ark for wildlife germplasm resources --Interview with Prof. Li Dezhu, Director of the Germplasm Bank of Wild Species in Southwest China

Recently, according to the Germplasm Bank of Wild Species (GBOWS), the seeds collecting team successfully collected seeds of several plants such as crucihimalaya himalaica and saussurea gnaphalodes at an altitude of approximately 6,200 meters on Mount Everest, setting a new record for plant seed collection at the highest altitude in China. The seeds will be preserved permanently in GBOWS and National Wild Plant Germplasm Resource Center.

The GBOWS is a major national scientific and technological infrastructure affiliated to the Kunming Institute of Botany of Chinese Academy of Sciences. The germplasm bank laid a solid foundation for protection and research work on biological diversity and national strategic biological resources collection, and the compliance with the Convention on Biological Diversity. At the time when the 15th meeting of the Conference of the Parties to the Convention on Biological Diversity (COP15) was held in Kunming, the reporter interviewed Prof. Li Dezhu, a researcher at the Kunming Institute of Botany(CAS) and director of the GBOWS.

Reporter: Why do we need to establish a germplasm bank since there have been so many PAs for biodiversity conservation in China?

Li: Only when there are more ways of protection can protection be more reliable. In situ conservation in nature reserves is an important method of protection, although many rare endemic species do not grow in reserves. In addition, in case natural or man-made disasters such as fire, freezing, or insect damage should occur in the nature reserve, the germplasm bank works as a necessary reserve to protect unique species and genetic diversity effectively.

The accelerated loss of biodiversity and germplasm resources is the main reason for the establishment of seed banks worldwide. After the establishment of the GBOWS, a considerable proportion of seeds of rare and endangered endemic species have been put into the bank, which has become a veritable refuge. We can use these germplasm resources to protect a species from extinction. Reporter: How to tell whether a seed is eligible for storage?

Li: It is not easy for a seed to be selected. Species are targeted and prioritized if they meet at least one of three standards－they are endangered, endemic or of economic importance. (the "3E" standard). Among them, the “endemic” seed should not only be unique to China but also grows in a narrow area. Following this standard, priorities for preservation have been given to rare and endangered plants on the top - and second-level national preservation such as Taxus wallichiana Zuccarini, Pinus squamata, Dipteronia dyerana Henry, and Craigia yunnanensis.

In addition to the “3E” standards, seeds have to undergo over 70 tests before they can be stored long-term. Testing starts from the beginning of the collection.

To ensure genetic diversity, researchers must collect seeds of the same kind from different habitats. Generally, 10,000 seeds of each plant need to be collected and stored, with a minimum of 2,500 seeds.

Generally, seeds can be stored for one to two years at most at room temperature. In order to extend their lives, they should be stored dry at a low temperature. Therefore, the collected seeds must go through multiple quality control procedures before they can be put into storage. In the cleaning room, researchers poured the seeds into a separator, where full seeds fell and empty seeds were blown aside. Researchers will also select random seeds for X-ray photography to check whether they are full or empty. The qualified healthy seeds left will continue to be cleaned, inspected, and counted. Then, the seeds are slowly dried, at a temperature of 15℃ and relative humidity of 15 percent for about a month. Then they are packed in airtight containers to enter the “hibernation" suite, a freezer at a temperature of minus 20℃. Here, seeds can survive for decades or even thousands of years. Under normal circumstances, the seeds of each species are divided into two parts, and stored in a backup library and an active library. The seeds in the former one will be kept forever, while seeds in the latter one will be tested for germination.

Reporter: How many germplasm resources are kept in the germplasm bank? What is the goal for future storage?

Li: After over 10 years of construction and operation, by the end of 2020, the GBOWS had preserved 85,046 accessions of 10,601 species, 24,100 accessions of in vitro culture materials of 2093 species, and 65,456 accessions of DNA materials of 7324 species. Also, there have been 22,800 accessions of 2,280 species of microbial strains, 60262 accessions of animal germplasm resources of 2,203 species. The number of seed accessions is close to that of the world's biggest seed bank－the Millennium Seed Bank in the United Kingdom and the Svalbard Global Seed Vault.

Though the basic scientific and technological work of collecting and preserving species is a laborious process, it is very worthwhile and meaningful to save plants and animals before they disappear so that they can be further explored and utilized. The germplasm bank is home and Noah’s Ark to plant seeds. As long as the bank is safe and sound, these rare wild germplasm resources will be protected from extinction. The aim of GBOWS is to conserve 19,000 species and 190,000 accessions. Also, we will exchange seeds with other seed banks in the world on a regular basis, which is very necessary for global germplasm resources security.

Contributed by Zhang Lei

Translated by Wu You