Conservation genetics of the endangered conifer Fitzroya cuppressoides in Chile and Argentina

PREMOLI, A.C.; KITZBERGER, T.; VEBLEN, T.T.

CONSERVATION GENETICS

SPRINGER

Año: 2000 vol. 1 p. 57 - 66

1566-0621

Abstract  Intraspecific patterns of genetic variation can often be used toidentify biogeographic divisions which can be especially useful in thedesign of conservation strategies. Although abundant empirical evidenceexist on the genetic characteristics of plant species from the NorthernHemisphere as well as tropical endangered taxa, this information isparticularly limited on threatened species from endemism-rich areas inthe southern Andes of Argentina and Chile. The objective of the currentstudy was to analyze the levels and distribution of the isozymevariation in Fitzroya cupressoides (Mol.) Johnst.(Cupressaceae), a rare conifer restricted to temperate rainforests ofnorthern Patagonia, and to evaluate the role of current conservationareas protecting the gene pool of this valuable long-lived conifer.Sampling schedules consisted of fresh foliage collected from 30 randomlyselected trees at each of 24 different populations located along thegeographic range of the species. Extraction of enzymes followed standardprocedures and homogenates were loaded in 12% starch gels whichwere analyzed by horizontal electrophoresis. Eleven enzyme systems wereresolved using a combination of four different buffer solutions whichyielded information on 21 putative loci, 52% of them werepolymorphic in at least one population. Relatively low levels ofwithin-population genetic variability were scored in Fitzroyapopulations which were approximately half of the typical levelspublished for gymnosperms (percent of polymorphic loci, P = 23 vs.53% and expected heterozygosity, HE = 0.077 vs. 0.155for Fitzroya and other conifers respectively). Substantialbetween-population variation was detected, and certain individualpopulations stand out as much more genetically variable than nearbypopulations, which in turn are located outside protected areas. Ourfindings suggest that if the objective is to protect key species likeFitzroya, spatially explicit genetic information can be auseful tool to attain this goal.