A new set of 182 microsatellites for Eucalyptus: characterization and mapping in a four-species consensus linkage map

Background Eucalyptus is the most widely planted hardwood crop in the tropical and subtropical world. Plantations of Eucalyptus species supply high-quality wood for industrial applications and are important sources of carbon neutral renewable energy in Brazil. E. grandis and E. urophylla and their hybrids are the most widely planted species in fast growing commercial forests in Brazil. E. globulus is the preferred raw material by the mills generating a pulp that is considered superior by the market. However as a pure species it does not grow adequately in Brazil but performs well in hybrid combinations. Breeding programs have increasingly incorporated E. globulus germplasm in fast moving elite populations. Molecular breeding in such populations will require information on markers, comparative mapping and QTL validation across pedigrees involving these different species. Highly multiallelic and transferable microsatellites not only are excellent tools for individual identification, but also provide robust and efficient framework genetic maps that serve well for mapping thousands of bialellic higher throughput markers such as Single Nucleotide Polymorphisms (SNPs) and Diversity Array Technology (DArT). Furthermore microsatellites provide a powerful way for QTL validation across species. We describe the development and characterization of 182 new microsatellites, most of them derived from ESTs and some from a genomic shotgun library. These markers, together with other previously developed ones were used to build a consensus map involving three different pedigrees derived from intercrossing four species of Eucalyptus.