Ex situ Gene Conservation for Conifers in the Pacific Northwest.

摘要

Recently, a group of public and private organizations responsible for managing much of the timberland in western Oregon and Washington formed the Pacific Northwest forest tree Gene Conservation Group (GCG) to ensure that the evolutionary potential of important regional tree species is maintained. The group is first compiling data to evaluate the genetic resource status of several species of conifers both at their original location (in situ) and at some other location (ex situ). We summarize the ex situ genetic resources present in seed orchards, provenance and progeny tests, seed stores, and clone banks both in western Oregon and Washington and in other countries with germplasm that originated in western Oregon and Washington. Some species, such as ponderosa pine (Pinus ponderosa Dougl. ex Laws.), noble fir (Abies procera Rehd.), and western hemlock (Tsuga heterophylla (Raf.) Sarg.) are found to have extensive genetic resources in ex situ forms. The resources for western redcedar (Thuja plicata Donn ex D. Don), for example, are more limited. Disease greatly influenced the development of ex situ genetic resources for western white pine (P. monticola Dougl. ex D. Don), sugar pine (P. lambertiana Dougl.), and Sitka spruce (Picea sitchensis (Bong.)). The summaries of genetic resources are, therefore, placed in the context of issues affecting each species. This provides land managers with the accurate information necessary for assessing the potential value of each resource for gene conservation and for prioritizing future actions.