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1.  Genetics, evolution and conservation of Bromeliaceae 
Genetics and Molecular Biology  2012;35(4 Suppl):1020-1026.
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 (FIS), while outcrossing species show low FIS. The degree of differentiation among populations (FST)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.
PMCID: PMC3571438  PMID: 23412953
bromeliads; cytogenetics; genetic diversity; population structure; reproductive biology
2.  Evolution of oil-producing trichomes in Sisyrinchium (Iridaceae): insights from the first comprehensive phylogenetic analysis of the genus 
Annals of Botany  2011;107(8):1287-1312.
Background and Aims
Sisyrinchium (Iridaceae: Iridoideae: Sisyrinchieae) is one of the largest, most widespread and most taxonomically complex genera in Iridaceae, with all species except one native to the American continent. Phylogenetic relationships within the genus were investigated and the evolution of oil-producing structures related to specialized oil-bee pollination examined.
Methods
Phylogenetic analyses based on eight molecular markers obtained from 101 Sisyrinchium accessions representing 85 species were conducted in the first extensive phylogenetic analysis of the genus. Total evidence analyses confirmed the monophyly of the genus and retrieved nine major clades weakly connected to the subdivisions previously recognized. The resulting phylogenetic hypothesis was used to reconstruct biogeographical patterns, and to trace the evolutionary origin of glandular trichomes present in the flowers of several species.
Key Results and Conclusions
Glandular trichomes evolved three times independently in the genus. In two cases, these glandular trichomes are oil-secreting, suggesting that the corresponding flowers might be pollinated by oil-bees. Biogeographical patterns indicate expansions from Central America and the northern Andes to the subandean ranges between Chile and Argentina and to the extended area of the Paraná river basin. The distribution of oil-flower species across the phylogenetic trees suggests that oil-producing trichomes may have played a key role in the diversification of the genus, a hypothesis that requires future testing.
doi:10.1093/aob/mcr080
PMCID: PMC3101146  PMID: 21527419
Oil-bee pollination; glandular trichomes; elaiophores; lipids; phylogeography; Sisyrinchieae; Olsynium; Solenomelus
3.  Population genetic structure of Sisyrinchium micranthum Cav. (Iridaceae) in Itapuã State Park, Southern Brazil 
Genetics and Molecular Biology  2012;35(1):99-105.
Sisyrinchium micranthum Cav. is a member of the family Iridaceae, which is distributed over the American continent. In Brazil, this species is found, not only in disturbed areas and coastal regions, but is also very common in urban centers, such as public parks, during the spring. Chromosome counts for North American specimens are 2n = 32 and 2n = 48, whereas in southern Brazil, there is a polyploidy series with three chromosome numbers, 2n = 16, 2n = 32, and 2n = 48. Population analyses using DNA molecular markers are inexistent for this species, in spite of its wide distribution and morphological variation. To study the genetic population structure of S. micranthum, five natural populations were accessed in a conservation park within the Atlantic Rain Forest Biome in southern Brazil. Here, the chromosome numbers 2n = 16 and 2n = 48 had already been described. Molecular analysis showed that the populations are highly structured with low gene flow among them. The population with 2n = 48 was genetically less variable than and distinct from the other populations. Population genetics in relation to cytogenetic data provided new insights regarding the genetic diversification and mating system of S. micranthum.
PMCID: PMC3313523  PMID: 22481881
Iridaceae; ISSR-PCR; mating system; population genetics; Sisyrinchium micranthum

Results 1-3 (3)