Microsatellites in the endangered species Dyckia distachya (Bromeliaceae) and cross-amplification in other bromeliads.

Microsatellite markers were isolated in Dyckia distachya, an endangered bromeliad from southern Brazil, which will be useful to assess the population genetic structure and reproductive success in introduced and natural populations of this species. Twenty microsatellite loci were developed from an enriched genomic library, and nine of these were amplified. The loci were characterized in 43 individuals from introduced and wild D. distachya populations. All nine loci were polymorphic, with four to ten alleles per locus. In an introduced population the observed and expected heterozygosities ranged from 0.136-0.667 and 0.543-0.877, respectively, while in a wild population it ranged from 0.000 to 0.895 and from 0.050 to 0.811, respectively. The development of these microsatellite markers will contribute to investigations of the reproductive potential and viability of introduced populations of D. distachya as well as the single known wild population. Cross-amplification in other Bromeliaceae species was successful, with high rates in four loci, demonstrating the applicability of these microsatellite markers in other taxa.

Genetics, evolution and conservation of Bromeliaceae.

Bromeliaceae is a morphologically distinctive and ecologically diverse family originating in the New World. Three centers of diversity, 58 genera, and about 3,140 bromeliad species are currently recognized. We compiled all of the studies related to the reproductive biology, genetic diversity, and population structure of the Bromeliaceae, and discuss the evolution and conservation of this family. Bromeliads are preferentially pollinated by vertebrates and show marked variation in breeding systems, from predominant inbreeding to predominant outcrossing, as well as constancy in chromosome number (2n = 2x = 50). Autogamous or mixed mating system bromeliads have a high inbreeding coefficient (F(IS)), while outcrossing species show low F(IS). The degree of differentiation among populations (F(ST))of species ranges from 0.043 to 0.961, which can be influenced by pollen and seed dispersal effects, clonal growth, gene flow rates, and connectivity among populations. The evolutionary history of the Bromeliaceae is poorly known, although some studies have indicated that the family arose in the Guayana Shield roughly 100 Mya. We believe that genetic, cytogenetic, and reproductive data will be essential for diagnosing species status and for assisting conservation programs.