Development and characterization of microsatellite markers for diploid populations of the wind-pollinated herb Mercurialis annua.

OBJECTIVE: Mercurialis annua is a wind-pollinated annual plant that has long been used as a model for the study of ploidy and sexual-systems evolution. However, no molecular markers are yet available for genetic studies of its diploid populations. Here, we develop and characterize a set of eight polymorphic microsatellite markers for diploid dioecious M. annua.

RESULTS: Following an SSR-enrichment protocol, 13 microsatellite markers were proposed, eight of which yielded successful amplification and polymorphism. We screened the eight microsatellite loci in 100 individuals. The number of alleles per marker ranged from 6 to 12, and observed heterozygosity ranged from 0.57 to 0.76. To estimate potential allele scoring errors, these individuals' offspring were genotyped for the same loci, and error rates were estimated from parentage analyses. Error rates ranged from 0 to 6.8%. Cross-amplification tests were performed for congeneric M. huetti and M. canariensis, with successful amplification for seven and six of the eight loci, respectively. The novel microsatellite markers proposed here will be crucial for a multitude of genetic studies of M. annua and further establish its importance as a model species for addressing ecological and population genetic questions.