Forest Genetic Monitoring: A Global Review on Methods, Results and Consequences of Genetic Studies and Long-Term Monitoring Projects

Numerous publications on forest genetic monitoring (FGM) and related topics in genetics and gene conservation have been published over the past three decades. This paper reviews the methods used in FGM and, more broadly, related scientific findings published to date, of which general conclusions can be applied worldwide in FGM. In the strict sense, long-term FGM projects have been established only in a few regions in Europe. The methodological basis (guidelines) for FGM has already been developed, specifically for European tree species and forest communities. In genetic analyses, traditional SSR markers are predominantly used, but SNP markers from new-generation sequencing are increasingly available. Nonetheless, there is a high level of variation in monitoring activities such as biodiversity, forest health, and forest genetics, likely due to the efforts of national (governmental) and international professional organizations. Early evaluation of the first FGM projects has already been published. Scientific evidence for FGM has been limited because of the low number of projects that represent a few geographic regions and species.