INVESTIGADORES
QUIROGA Maria paula
congresos y reuniones científicas
Título:
Geographic range effects on the genetic characteristic of two southern South America Podocarpus species
Autor/es:
QUIROGA, M. P.
Lugar:
Bariloche
Reunión:
Congreso; VI Southern Connection Congress; 2010
Resumen:
Plant genetic variation presents high association in relation to geographic range. However, climatic events of the Quaternary could have differentially affected genetic characteristics of widespread South American Podocarpus. I studied levels of isozyme variation in relation to geographic range and population continuity. I analyzed 14 and 18 populations of P. nubigena and P. parlatorei using 12 and 14 isozyme loci, respectively. For each species, population diversity parameters and among-population divergence was estimated. Mean within-population polymorphism and diversity (PSS and HE) were high although statistically different between species: Podocarpus nubigena PSS=65 and HE=0.218, whereas P. parlatorei presented PSS=43 and HE=0.151. Degree of divergence was FST=0.181 and 0.109 among populations of P. nubigena and P. parlatorei which can be explained in relation to Quaternary climatic events. Thus, P. nubigena could have suffered restrictions for gene flow during glacial periods due to the presence of different genetic variants in several populations. On the other hand, P. parlatorei has probably expanded its range and also populations have maintained  high rate of gene flow promoted genetic homogenization of populations.