• Home
• Science Strategy
• Science Teams
• Projects
  • Molecular Population Genetics of Four Closely Related Alcantarea Species (Bromeliaceae) Adapted to ‘Inselbergs’ in the Atlantic Rainforest of Brazil
• People
• Publications
• Acronyms

Molecular Population Genetics of Four Closely Related Alcantarea Species (Bromeliaceae) Adapted to ‘Inselbergs’ in the Atlantic Rainforest of Brazil

Flowering population of the bat-pollinated, "inselberg" - adapted  bromeliad Alcantarea glaziouana in the state of Rio de Janeiro, Brazil. Photo: C. Lexer.

The inselbergs of the Brazilian Atlantic Rain Forest form terrestrial “islands” that are [ahl1] isolated from the surrounding forest by steep gradients in humidity, temperature and irradiation, and by drastic changes in soil substrates. Bromeliads (Bromeliaceae) are particularly well represented among plants adapted to the extreme growing conditions on inselbergs.

Thelma Barbarà Santos, a PhD student at Open University/RBG Kew started this project in 2003 to study the molecular population genetics of four members of the Alcantarea species complex endemic to inselbergs of coastal Atlantic Brazil, which includes Alcantarea imperialis, A. geniculata, A. glaziouana and A. regina. The PhD project is supervised by Dr Mike Fay (Director of studies), Dr Simon Mayo, Dr Christian Lexer, and Dr Colin Clubbe at Kew, and Dr Gustavo Martinelli at Jardim Botanico do Rio de Janeiro and is expected to be finished by early 2007 if carried out full-time. Its aim is to study genetic variability at nuclear DNA microsatellites and, if sufficient polymorphism is found, at plastid DNA markers. Fundamental questions regarding the breeding system, metapopulation dynamics, and distribution of genetic diversity across a highly fragmented landscape will be addressed.

This project will ask specific questions: (1) What is the relative importance of sexual recombination versus asexual (clonal) reproduction in generating the patterns of genetic variability observed within each species? (2) Is gene flow between inselberg populations sufficient to maintain Alcantarea species as cohesive units? (3) How different, or how similar, are local genetic structures on different inselbergs? (4) How well do patterns of genetic diversity correlate among co-occurring Alcantarea species, and is there any genetic evidence for interspecific gene flow in the past? (5) What are the differences between patterns of variability observed at nuclear and plastid DNA markers, and are these differences useful for inferring the relative importance of pollen vs. seed dispersal? By the end of 2005, approximately 70% of the data had been collected, a first manuscript was in preparation, and results of the work were presented at the International Botanical Congress (IBC) in Vienna, 12 -16 July 2005, and at the Population Genetics Group (PopGroup) meeting in Edinburgh, UK, 13 -16 December 2005.

Kew Home | Science Directory | Copyright & Privacy