From keystone species to conservation: conservation genetics of wax palm Ceroxylon quindiuense in the largest wild populations of Colombia and selected neighboring ex situ plant collections

摘要

The cloud forest of the Andean Region contains a high biodiversity. Unfortunately, human land use has caused most of the forest to become fragmented, negatively impacting many species due to the reduction of and constant change within the local habitat. In Colombia, these fragmentation triggers can include agriculture, livestock, and corridors for tourism. Conservation strategies focusing on keystone species could have more impact and better results to recover ecosystem dynamics. The wax palm Ceroxylon quindiuense (C. quindiuense) is an endemic and keystone species in cloud forests with a distribution across the three cordilleras of Colombia. Despite its ecological, economic and social importance, most forests of C. quindiuense are endangered; the most severely affected residing in small isolated populations in Central Cordillera. Nevertheless, these populations seem to retain a high genetic diversity. Because of this, the goal of conservation strategies should focus on retaining genetic diversity instead of increasing it. Because it can take as long as 80 years for C. quindiuense to reach maturity, our approach entails the introduction of juveniles (around 30 years) with genetic profiles similar to wild populations in order to augment population size, connect isolated populations, and avoid outbreeding. We evaluated the genetic makeup of three neighboring ex situ collections of living palms and compared them with the genetic profile of three wild populations of Central Cordillera. Multivariate analysis was used to assess patterns of genetic similarity and assign individuals to infer genetic clusters between collections and wild populations. Expected heterozygosity (He) of ex situ collections was lower (0.56) than wild populations (0.63), and the percentage of private alleles was higher in the wild populations (25%) than ex situ collections (10%). Collections Milan and Botanic Garden show genetic similarity with the Cocora and La Linea populations while the Toche and Roso collections were the most genetically distinct among the ones studied. Our results are that conservation programs should consider each population as a different evolutionary unit and protect them as such.