Genome shotgun sequencing and development of microsatellite markers for gerbera (<i>Gerbera hybrida</i> H.) by 454 GS-FLX

Abstract

The objective of this research was to develop and characterize microsatellite markers for gerbera. We used shotgun sequencing with Roche 454 GS-FLX Titanium technology to identify microsatellite loci in gerbera genomic DNA (Gerbera hybrida). The total length of non-redundant sequences obtained was 22,527,019 bp, which consisted of 3,085 contigs and 28,249 singletons. We assembled 61,958 reads into 3,085 contigs, of which 114 (3.70%) contained microsatellite repeats. The average G+C content was 39.3%. Functional annotation to known sequences yielded 14.7% unigenes in the ‘Raon’ cultivar. Analysis of the gerbera genome DNA (‘Raon’) general library showed that sequences of (AT), (AG), (AAG) and (AAT) repeats appeared most often, whereas (AC), (AAC) and (ACC) were the least frequent. Primer pairs were designed for 80 loci. Only eight primer pairs produced reproducible polymorphic bands in the 28 gerbera accessions analyzed. A total of 30 alleles were identified from the eight polymorphic SSR loci, with two to eight alleles per locus (average level of 3.75). These markers will be useful for investigating genetic diversity and differentiation in gerbera.

Keywords: Genetic diversity, genomics, microsatellite isolation, pyrosequencing, SSRs.

African Journal of Biotechnology Vol. 11(29), pp. 7388-7396, 10 April, 2012