Spatially biased collections and the failure to cover all wild genetic clusters in plant populations under ex situ conservation

doi:10.1016/j.pld.2025.09.001

Plant Diversity ›› 2026, Vol. 48 ›› Issue (01): 75-83.DOI: 10.1016/j.pld.2025.09.001

Spatially biased collections and the failure to cover all wild genetic clusters in plant populations under ex situ conservation

Zhiqiang Xiao^a,b,c,d, Hui Liu^e,f, Guiyun Huang^a,b,c, Di Wu^a,b,c, Liwen Qiu^a,b,c, Jinhua Wu^a,b,c, Xinzeng Wei^d,g, Mingxi Jiang^d,g

a National Engineering Research Center of Eco-Environment Protection for Yangtze River Economic Belt, Beijing 100038, China;
b Hubei Key Laboratory of Rare Resource Plants in Three Gorges Reservoir Area, Yichang 443134, China;
c Centre for Yangtze River Biodiversity, China Three Gorges Corporation, Wuhan 430010, China;
d State Key Laboratory of Plant Diversity and Specialty Crops, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan 430074, China;
e Key Laboratory of Ecological Impacts of Hydraulic-Projects and Restoration of Aquatic Ecosystem of Ministry of Water Resources, Institute of Hydroecology, Ministry of Water Resources and Chinese Academy of Sciences, Wuhan, 430079, China;
f Institute of Hydroecology, Ministry of Water Resources and Chinese Academy of Sciences, Wuhan 430079, China;
g University of Chinese Academy of Sciences, Beijing 100049, China

收稿日期:2025-05-28 修回日期:2025-08-28 出版日期:2026-01-25 发布日期:2026-03-05
通讯作者: Xinzeng Wei,E-mail:xzwei@wbgcas.cn
基金资助:
We thank Ms. Lvjuan Wang for her assistance in the fieldwork. This work was financially supported by National Key Research and Development Program of China (2024YFF1307400), Hubei Provincial Natural Science Foundation and Three Gorges Innovation Development Joint Fund (Grant No. 2023AFD195), and China Three Gorges Corporation (NBZZ202300130).

Spatially biased collections and the failure to cover all wild genetic clusters in plant populations under ex situ conservation

Zhiqiang Xiao^a,b,c,d, Hui Liu^e,f, Guiyun Huang^a,b,c, Di Wu^a,b,c, Liwen Qiu^a,b,c, Jinhua Wu^a,b,c, Xinzeng Wei^d,g, Mingxi Jiang^d,g

a National Engineering Research Center of Eco-Environment Protection for Yangtze River Economic Belt, Beijing 100038, China;
b Hubei Key Laboratory of Rare Resource Plants in Three Gorges Reservoir Area, Yichang 443134, China;
c Centre for Yangtze River Biodiversity, China Three Gorges Corporation, Wuhan 430010, China;
d State Key Laboratory of Plant Diversity and Specialty Crops, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan 430074, China;
e Key Laboratory of Ecological Impacts of Hydraulic-Projects and Restoration of Aquatic Ecosystem of Ministry of Water Resources, Institute of Hydroecology, Ministry of Water Resources and Chinese Academy of Sciences, Wuhan, 430079, China;
f Institute of Hydroecology, Ministry of Water Resources and Chinese Academy of Sciences, Wuhan 430079, China;
g University of Chinese Academy of Sciences, Beijing 100049, China

Received:2025-05-28 Revised:2025-08-28 Online:2026-01-25 Published:2026-03-05
Contact: Xinzeng Wei,E-mail:xzwei@wbgcas.cn
Supported by:
We thank Ms. Lvjuan Wang for her assistance in the fieldwork. This work was financially supported by National Key Research and Development Program of China (2024YFF1307400), Hubei Provincial Natural Science Foundation and Three Gorges Innovation Development Joint Fund (Grant No. 2023AFD195), and China Three Gorges Corporation (NBZZ202300130).

摘要/Abstract

摘要： Successful ex situ conservation of plant populations requires a high degree of genetic representativeness. However, spatially biased sampling in ex situ conservation efforts may fail to capture all wild genetic clusters for species with range-wide genetic structure. To investigate the extent of spatially biased sampling in living collections and the coverage of wild genetic clusters in plant populations under ex situ conservation worldwide, we combined a global synthesis of ex situ conservation efforts with a case study of an endangered riparian plant species, Myricaria laxiflora. Our analysis of ex situ conservation worldwide revealed that the majority (82.6%) of ex situ populations fail to cover all wild genetic clusters, largely due to spatially biased sampling with low geographic coverage. Our case study of M. laxiflora showed that genetic diversity differed between the ex situ and upstream populations, while it was comparable between ex situ populations and other wild populations. However, current ex situ populations did not cover all wild genetic clusters, as the upstream genetic cluster was previously uncollected. Our study suggests that the failure to cover all wild genetic clusters in ex situ populations is a widespread issue, and ex situ populations with high genetic diversity can also fail to cover all wild genetic clusters. In future ex situ conservation programs, both the importance of high genetic diversity and the high coverage of wild genetic clusters should be prioritized.

关键词: Conservation genomics, Genetic representativeness, Ex situ conservation, Genetic composition, Geographic coverage, Spatially biased sampling

Abstract: Successful ex situ conservation of plant populations requires a high degree of genetic representativeness. However, spatially biased sampling in ex situ conservation efforts may fail to capture all wild genetic clusters for species with range-wide genetic structure. To investigate the extent of spatially biased sampling in living collections and the coverage of wild genetic clusters in plant populations under ex situ conservation worldwide, we combined a global synthesis of ex situ conservation efforts with a case study of an endangered riparian plant species, Myricaria laxiflora. Our analysis of ex situ conservation worldwide revealed that the majority (82.6%) of ex situ populations fail to cover all wild genetic clusters, largely due to spatially biased sampling with low geographic coverage. Our case study of M. laxiflora showed that genetic diversity differed between the ex situ and upstream populations, while it was comparable between ex situ populations and other wild populations. However, current ex situ populations did not cover all wild genetic clusters, as the upstream genetic cluster was previously uncollected. Our study suggests that the failure to cover all wild genetic clusters in ex situ populations is a widespread issue, and ex situ populations with high genetic diversity can also fail to cover all wild genetic clusters. In future ex situ conservation programs, both the importance of high genetic diversity and the high coverage of wild genetic clusters should be prioritized.

Key words: Conservation genomics, Genetic representativeness, Ex situ conservation, Genetic composition, Geographic coverage, Spatially biased sampling

Zhiqiang Xiao, Hui Liu, Guiyun Huang, Di Wu, Liwen Qiu, Jinhua Wu, Xinzeng Wei, Mingxi Jiang. Spatially biased collections and the failure to cover all wild genetic clusters in plant populations under ex situ conservation[J]. Plant Diversity, 2026, 48(01): 75-83.

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Spatially biased collections and the failure to cover all wild genetic clusters in plant populations under ex situ conservation

Spatially biased collections and the failure to cover all wild genetic clusters in plant populations under ex situ conservation

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