title: Genomic sequencing and microsatellite marker development for Boswellia papyrifera, an economically important but threatened tree native to dry tropical forests.
abstract: Microsatellite (or simple sequence repeat, SSR) markers are highly informative DNA markers often used in conservation genetic research. Next-generation sequencing enables efficient development of large numbers of SSR markers at lower costs. Boswellia papyrifera is an economically important tree species used for frankincense production, an aromatic resinous gum exudate from bark. It grows in dry tropical forests in Africa and is threatened by a lack of rejuvenation. To help guide conservation efforts for this endangered species, we conducted an analysis of its genomic DNA sequences using Illumina paired-end sequencing. The genome size was estimated at 705 Mb per haploid genome. The reads contained one microsatellite repeat per 5.7 kb. Based on a subset of these repeats, we developed 46 polymorphic SSR markers that amplified 2-12 alleles in 10 genotypes. This set included 30 trinucleotide repeat markers, four tetranucleotide repeat markers, six pentanucleotide markers and six hexanucleotide repeat markers. Several markers were cross-transferable to Boswellia pirrotae and B. popoviana. In addition, retrotransposons were identified, the reads were assembled and several contigs were identified with similarity to genes of the terpene and terpenoid backbone synthesis pathways, which form the major constituents of the bark resin.
authors.affiliation: Wageningen UR Plant Breeding, Wageningen University and Research Center, PO Box 386, NL-6700 AJ Wageningen, The Netherlands Center for Ecosystem Studies, Forest Ecology and Forest Management Group, Wageningen University and Research Center, PO Box 47, NL-6700 AA Wageningen, The Netherlands Wondo Genet College of Forestry and Natural Resources, PO Box 128, Shashemene, Ethiopia.
authors.forename: A B
authors.initials: AB
authors.lastname: Addisalem
authors.affiliation: Wageningen UR Plant Breeding, Wageningen University and Research Center, PO Box 386, NL-6700 AJ Wageningen, The Netherlands.
authors.forename: G Danny
authors.initials: GD
authors.lastname: Esselink
authors.affiliation: Center for Ecosystem Studies, Forest Ecology and Forest Management Group, Wageningen University and Research Center, PO Box 47, NL-6700 AA Wageningen, The Netherlands.
authors.forename: F
authors.initials: F
authors.lastname: Bongers
authors.affiliation: Wageningen UR Plant Breeding, Wageningen University and Research Center, PO Box 386, NL-6700 AJ Wageningen, The Netherlands rene.smulders@wur.nl.
authors.forename: M J M
authors.initials: MJ
authors.lastname: Smulders
keywords: Conservation genetics; SSR; resin; terpene biosynthesis; terpenoid; tropical dry forest.