Abstract:

Genetic diversity is an important component of biodiversity. However, the overexploitation of natural resources and habitat fragmentation have severely degraded the genetic diversity of many affected species. Wild Plant with Extremely Small Populations (WPESP) are in urgent need of rescue, their genetic diversity are of great significance for studying the endangerment mechanism and providing conservation strategies. Habitat fragmentation might reduce genetic diversity, increase genetic differentiation among populations or limit gene flow. However, biological and ecological factors of threatened species, such as the reproductive characteristic and the demographic history, may also impact the genetic effects of recent habitat fragmentation. For gymnosperms, genetic composition can be quite stable when facing habitat fragmentation because of their lengthy generation time. However, in the long term, the loss of genetic diversity will be unrecoverable. In this review paper, we survey genetic studies of threatened gymnosperms, summarize endangerment mechanisms under habitat fragmentation, and finally recommend conservation strategies for gymnosperms. The findings of this paper indicate that a comprehensive understanding of the endangerment mechanisms through genetic diversity studies is important for effective and efficient conservation of Wild Plant with Extremely Small Populations.

Key words: Wild Plant with Extremely Small Populations (WPESP), gymnosperms, genetic diversity, endangerment mechanism, conservation strategy