Ex situ collections and their potential for the restoration of extinct plants

Abstract

The alarming current and predicted species extinction rates have galvanized conservationists in their efforts to avoid future biodiversity losses, but for species extinct in the wild, few options exist. We posed the questions, can these species be restored, and, if so, what role can ex situ plant collections (i.e., botanic gardens, germplasm banks, herbaria) play in the recovery of plant genetic diversity? We reviewed the relevant literature to assess the feasibility of recovering lost plant genetic diversity with using ex situ material and the probability of survival of subsequent translocations. Thirteen attempts to recover species extinct in the wild were found, most of which used material preserved in botanic gardens (12) and seed banks (2). One case of a locally extirpated population was recovered from herbarium material. Eight (60%) of these cases were successful or partially successful translocations of the focal species or population; the other 5 failed or it was too early to determine the outcome. Limiting factors of the use of ex situ source material for the restoration of plant genetic diversity in the wild include the scarcity of source material, low viability and reduced longevity of the material, low genetic variation, lack of evolution (especially for material stored in germplasm banks and herbaria), and socioeconomic factors. However, modern collecting practices present opportunities for plant conservation, such as improved collecting protocols and improved cultivation and storage conditions. Our findings suggest that all types of ex situ collections may contribute effectively to plant species conservation if their use is informed by a thorough understanding of the aforementioned problems. We conclude that the recovery of plant species currently classified as extinct in the wild is not 100% successful, and the possibility of successful reintroduction should not be used to justify insufficient in situ conservation.

Meta‐analysis of genetic representativeness of plant populations under ex situ conservation in contrast to wild source populations

“…2017; Abeli et al. 2020). Living plant collections and seed banks are the 2 main types of ex situ conservation for wild plants (Schoen & Brown 2001; Oldfield 2009; Mounce et al.…”

Thermal Requirements Underpinning Germination Allude to Risk of Species Decline from Climate Warming

“…In an era of unprecedented biodiversity loss, seed banks have become a vital means to support the conservation of the genetic diversity of flowering plant species [ 1 , 2 ]. The storage of seeds complements plant conservation in the wild and provides the raw material for population augmentation and the creation of new populations in the face of biodiversity decline and loss [ 3 , 4 ]. Seed banks also provide the raw material for research into the germination requirements of species [ 5 , 6 ], including documenting seed responses to a diverse range of threatening processes [ 7 , 8 , 9 , 10 ].…”

What Are the Grand Challenges for Plant Conservation in the 21st Century?

“…Data on distribution and abundance are required to inform in-situ conservation efforts such as species-focused conservation interventions and protected area planning and prioritization, as well as inter-situ conservation and assisted migration (Richardson et al, 2009). The resources of ex-situ conservation such as seed banks, arboreta and botanic gardens could complement in-situ conservation and play a vital role in restoration projects and conservation of genetic diversity (Mounce et al, 2017, Abeli et al, 2020.…”