DIVERSIDADE GENÉTICA E SISTEMA DE REPRODUÇÃO EM UMA POPULAÇÃO BASE DE Eucalyptus camaldulensis Dehnh. PROCEDENTE DE KATHERINE RIVER, AUSTRÁLIA
DOI:
https://doi.org/10.24278/2178-5031.2009212222Keywords:
genetic diversity, Eucalyptus, microsatellite markers, outcrossing rateAbstract
The aim of this work was to evaluate the genetic diversity and the mating system of a base population of , composed of 25 open-pollinated families, located in the experimental station of UNESP Ilha Solteira, in Selvíria MS. One hundred individuals from 25 families (4 trees/family) were genotyped through eight microsatellite loci. All evaluated loci were polymorphic. The observed heterozigosity in the seed-trees ( ) was significantly higher than observed in offspring ( ), indicating that some process is reducing the heterozigosity in the offspring. The fixation index in the seed-trees ( ) was significantly lower than detected in offspring ( ), suggesting selection for heterozygotes. The estimative of the multilocus outcrossing rate was high ( ), but significant different from unity (1.0), revealing that the species have a mixed mating system with predominance of outcrossing. The rate of mating among relatives was also high and significant different from zero ( < 0.05), which together with the selfing rate explain the high inbreeding detected in the offspring. In general terms, high genetic diversity was detected in seed-tree and offspring. Since the genetic diversity is the raw material for genetic conservation and breeding programs, this result indicates that the studied population has high potential to be used for these purposes.
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