Genetic diversity and population structure of a drought-tolerant species of Eucalyptus, using microsatellite markers
Given the impact of climate change on the availability of water resources, it becomes necessary the use of plant species well suited to planting on dryland sites. Eucalyptus cladocalyx, a native tree of South Australia, is capable of growing under relatively dry environments and saline soils. Two hundred twenty simple sequence repeat (microsatellites) markers, from a consensus linkage map of Eucalyptus, were selected to examine genetic diversity and population structure in a collection of E. cladocalyx introduced to southern Atacama Desert, Chile. A total of 130 microsatellites were successfully amplified, some of which are associated with quantitative traits of interest in Eucalyptus. Genetic analysis revealed a total of 457 alleles, ranging from 2 to 8 alleles per locus. A moderate level of genetic diversity (He = 0.492) and differentiation (FST = 0.086) was found among the populations. Mount Remarkable and Marble Range showed the highest and lowest level of genetic diversity, respectively. The Bayesian clustering analysis revealed three homogeneous genetic groups confirming that the individuals of E. cladocalyx from natural forest are highly and significantly structured. These results provide a novel information for the development of breeding strategies in E. cladocalyx by using marker-assisted selection in regions with low rainfall patterns.
KeywordsBayesian clustering Drylands Genetic differentiation SSR markers
Markov chain Monte Carlo
Quantitative trait loci
Simple sequence repeat
The authors thank Mr. Augusto Gomes for providing the samples of E. cladocalyx. Osvin Arriagada thanks CONICYT for a doctoral fellowship (CONICYT-PCHA/Doctorado Nacional/año 2013-folio 21130812).
This study was funded by FONDECYT (Grant Number 1130306).
Compliance with ethical standards
Conflict of interest
Freddy Mora, Osvin Arriagada, Paulina Ballesta, and Eduardo Ruiz declare that they have no conflict of interest.
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