Abstract:

Background: Ex situ conservation is an important approach to conserving rare or endangered plants. The National Botanical Garden System Layout Plan of China proposed that more than 70% of the rare or endangered plants should be under effective ex situ conservation by 2035. However, the criteria that constitute effective ex situ conservation and the methods for its implementation remain poorly defined. This paper addresses these critical issues. 

Results: Survival and normal growth, successful reproduction, self-sustainability, and species authenticity can serve as indicators for evaluating different extents of success of ex situ conservation, which are grouped into ex situ preservation and effective ex situ conservation. This paper suggests self-sustainability, genetic distinctiveness, and genetic integrity as the standards for effective ex situ conservation. Accordingly, four recommendations are proposed for implementing effective ex situ conservation. 

Perspective: The definition, standards, and recommendations presented in this paper will help to clarify the concept of effective ex situ conservation, thereby facilitating the achievement of the goals set forth in The National Botanical Garden System Layout Plan of China.

Key words: rare or endangered plants, effective ex situ conservation, self-sustainability, genetic distinctiveness, genetic integrity