Estrutura e dinâmica da erva-de-passarinho Psittacanthus robustus Mart. em manchas de habitat em três áreas de cerrado

• Ano de defesa: 2010
• Autor(a) principal: Teodoro, Grazielle Sales
• Orientador(a): Van Den Berg, Eduardo
• Banca de defesa: Arruda, Rafael Soares
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: UNIVERSIDADE FEDERAL DE LAVRAS
• Programa de Pós-Graduação: DBI - Departamento de Biologia
• País: BRASIL
• Palavras-chave em Português: Parasitismo; Hemiparasita; Metapopulação; Vochysia thyrsoidea; Loranthaceae; Parasitism; Mistletoe; Metapopulation
• Área do conhecimento CNPq: CNPQ_NÃO_INFORMADO
• Link de acesso: https://repositorio.ufla.br/handle/1/3163

Psittacanthus robustus Mart. (Loranthaceae) is mistletoe that colonizes mainly Vochysiaceae species in Brazilian Cerrado. Vochysia thyrsoidea Pohl (Vochysiaceae), a tree species, is one of the main hosts of P. robustus. The objective of this study is to evaluate the structure and metapopulational dynamics of the mistletoe on V. thyrsoidea population in three Savannah areas. The studied was carried in three areas, the first is located in the Lavras city (Parque Ecológico Quedas do Rio Bonito), this site is a "Cerrado Rupestre". The second and third areas are located in the Carrancas municipality. The site Carrancas-Zilda (CZ) is a "Cerrado sensu stricto" physiognomy and the area Carrancas-Esmeralda é a "Cerrado Rupestre". Were sampled 2.8 hectares in each area. All V. thyrsoidea individuals (habitat patch) with height more than two meters were inventoried. To evaluate the P. robustus parasitism pattern, all the individuals found in V. thyrsoidea trees were recorded. The populations were monitored at intervals of six months. Comparing the sites, there were differences in the number of P. robustus individuals among the areas due to fire. The site CE was burned before the study and in areas PEQRB and CZ there weren´t fire. Still didn´t report in the literature about the P. robustus fire sensitivity. There was a strong parasitism pattern, where the biggest V. thyrsoidea individuals were the most infected and, the P. robustus showed an aggregation of individuals at the local level regardless of the pattern found for the host species. In relation to the P. robustus dynamics, the rates of change were low for the host and higher for mistletoe. The control area (without fire) PEQRB was the site with the greatest mortality of V. thyrsoidea. In this area all the patches died had mistletoe, probably; the parasitism was the cause of the extinction of the patches. Occurred the local subpopulation extinction without the patch extinction, were observed re-colonization and the dynamics among the habitat patches were asynchronous. In conclusion, dynamics of P. robustus can be viewed like a metapopulation.