English

Abstract

The conservation of genetic diversity in tree populations is an essential component of sustainable forest management. Picea chihuahuana Martínez is an endemic conifer species in Mexico and is considered to be endangered. P. chihuahuana covers a total area of no more than 300 ha at the Sierra Madre Occidental, a mountain range that harbor a high diversity of tree species. There are 40 populations of the species that have been identified in the region, and it cannot be found elsewhere. These populations form clusters within gallery forests and are usually associated with eight other tree genera. The P. chihuahuana community is mostly well preserved. Owing to its remarkable characteristics and high conservation value, P. chihuahuana has been the subject of several studies aimed at learning more about the genetic structure, ecology and potential effects of climate change. However, the overall applicability of such studies is to confirm a dataset to develop management tools to help decision makers and to implement preservation and conservation strategies using genetic diversity. In this review, we summarize the studies carried out to date, emphasizing those concerning the most important aspects of the genetic diversity of the species. Although, genetic diversity in Chihuahua spruce is mostly moderate compared with other Picea, this species is unlikely to survive without help due to its small and isolated populations. Efforts should focus on the protection of populations displaying the highest degree of genetic variation because these populations have the greatest potential for adaptive evolution. Finally, continuous monitoring of size and genetic diversity of the current populations in situ is essential.   Key words: Pinabete, spruce, endangered species, heterozygosity, genetic variability, Sierra Madre Occidental.