Increasing global changes have caused many rare and endangered plants facing the risk of extinction. Ex situ conservation is considered to be an important protection strategy to relieve the extinction risk of rare and endangered plants. Plant ex situ collections often face limitations, such as the lack of detailed origin information, insufficient genetic representation, and adaptability to new environments.  

The Vegetation Ecology Group of Wuhan Botanical Garden evaluated the effectiveness of ex situ conservation of plant species based on the ex situ collections in Jiugongshan National Nature Reserve, Hubei in 1980s. 

Combining the information provided by the senior colleagues and literature, researchers selected five relict tree species (i.e., Davidia involucrata, Dipteronia sinensis, Tapiscia sinensis, Tetracentron sinense, and Cercidiphyllum japonicum), which have been successfully transplanted more than 20 years outside their natural range, to test whether these tree species have been well conserved genetically.  

Results found high levels of genetic representation of ex situ populations and weak genetic structure among ex situ and wild-source populations for each species. Both geographic and genetic factors may influence the evaluation of ex situ conservation. Due to the transplanted individuals of target species have wide distributions in their natural habitat, it should pay attention to geographic factors to conserve these endangered species in the long term. 

This study suggests that more additional ex situ collections from different maternal lines across ex situ institutions or the distribution range of the target species, and complete collection records and optimal sampling strategies are needed for effective ex situ plant conservation in the future study. 

The relevant results are titled as "Exploring the origin and genetic representation of ex situ living collections of five endangered tree species established for 20-35 years" and published in Global Ecology and Conservation.