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

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

CONSERVATION GENETICS

SPRINGER

Año: 2000 p. 57 - 66

1566-0621

Intraspecific patterns of genetic variation can often be used to identify biogeographic divisions which can be especially useful in the design of conservation strategies. Although abundant empirical evidence exist on the genetic characteristics of plant species from the Northern Hemisphere as well as tropical endangered taxa, this information is particularly limited on threatened species from endemism-rich areas in the southern Andes of Argentina and Chile. The objective of the current study was to analyze the levels and distribution of the isozyme variation in Fitzroya cupressoides (Mol.) Johnst. (Cupressaceae), a rare conifer restricted to temperate rainforests of northern Patagonia, and to evaluate the role of current conservation areas protecting the gene pool of this valuable longlived conifer. Sampling schedules consisted of fresh foliage collected from 30 randomly selected trees at each of 24 different populations located along the geographic range of the species. Extraction of enzymes followed standard procedures and homogenates were loaded in 12% starch gels which were analyzed by horizontal electrophoresis. Eleven enzyme systems were resolved using a combination of four different buffer solutions which yielded information on 21 putative loci, 52% of them were polymorphic in at least one population. Relatively low levels of within-population genetic variability were scored in Fitzroya populations which were approximately half of the typical levels published for gymnosperms (percent of polymorphic loci, P = 23 vs. 53% and expected heterozygosity, HE = 0.077 vs. 0.155 for Fitzroya and other conifers respectively). Substantial between-population variation was detected, and certain individual populations stand out as much more genetically variable than nearby populations, which in turn are located outside protected areas. Our findings suggest that if the objective is to protect key species like Fitzroya, spatially explicit genetic information can be a useful tool to attain this goal.