Micobiota folícola de Dimorphandra wilsonii, espécie arbórea brasileira ameaçada de extinção

• Ano de defesa: 2012
• Autor(a) principal: Silva, Meiriele da
• Orientador(a): Barreto, Robert Weingart
• Banca de defesa: Costa, Maurício Dutra , Evans, Harold Charles , Bezerra, José Luiz , Furtado, Gleiber Quintão
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Viçosa
• Programa de Pós-Graduação: Mestrado em Fitopatologia
• Departamento: Etiologia; Epidemiologia; Controle
• País: BR
• Palavras-chave em Português: Conservação; Fungos; Novidades taxonômicas; Micologia
• Palavras-chave em Inglês: Conservation; Fungi; New taxonomic; Mycology
• Área do conhecimento CNPq: CNPQ::CIENCIAS AGRARIAS::AGRONOMIA::FITOSSANIDADE::FITOPATOLOGIA
• Link de acesso: http://locus.ufv.br/handle/123456789/4401

Dimorphandra wilsonii (Fabaceae), commonly known as faveiro de Wilson , is an endemic species of Minas Gerais, which occurs in the transition between the Cerrado and the Atlantic Forest, north of Belo Horizonte. It was included in the list of endangered species in the state of Minas Gerais, in the general list of endangered Brazilian flora, and in the list kept by the International Union for Conservation of Nature (IUCN), where it appears as critically endangered, the level that precedes extinction. In contrast, Dimorphandra mollis Benth., a plant that is taxonomically very close to the faveiro de Wilson , commonly known as faveira and falso barbatimão , is widely distributed in the Brazilian Cerrado mainly in the states of Goiás, Mato Grosso, Minas Gerais and São Paulo. This work represents a continuation of the investigations started some years ago aimed at contributing to the knowledge of the mycobiota associated with endangered Brazilian plants and, therefore, also possibly threatened with extintion. A survey of the foliicolous mycobiota of D. wilsonii was undertaken and parallel to that, also the mycobiota of D. mollis occurring in the same vicinity as D. wilsonii was investigated. Such a kind of mycological study was expected to yield both interesting mycological information and to contribute towards the generation of a preliminary list of fungal species in danger of extinction. The inclusion of the mycobiota of D. mollis in the surveys aimed at excluding the fungi occurring on both plants from such a list with regards to the risk of extinction because of host loss. The surveys were concentrated in the municipality of Caetanópolis and Paraopeba, Juatuba, Fortuna de Minas, Sete lagoas e Pequi. Fifteen fungal species were found, described and illustrated of which ten had the ITS region (Internal Transcribed Spacer) the rDNA and LSU (Large Subunit 28S) partially sequenced and phylogenetically compared with other sequences available in GenBank, in order to generate a more complete understanding of the taxonomic relationships. Thirteen fungal species were found associated with D. wilsonii: Vesiculohyphomyces cerradensis, Johansonia chapadiensis, Trichomatomyces byrsonimae, Piricauda paraguayensis, Geastrumia polystigmatis, Phillipsiella atra, Stomiopeltis suttoniae, Microcalliopsis dipterygis, Janetia sp. 1 (probably new species), Byssogene sp. (probably new species), Pseudocercospora sp. (probably new species), Pseudocercosporella sp. (probably new species), cf. Radulidium sp. (probably new genus). Six species were found associated with D. mollis: Trichomatomyces byrsonimae, Piricauda paraguayensis, Pseudocercospora sp. (probably new species), Pseudocercosporella sp. (probably new species), Janetia sp. 2 (probably new species) and Alveariospora distoseptata (proposed as a new genus and species). The species Vesiculohyphomyces cerradensis, Trichomatomyces byrsonimae, Piricauda paraguayensis, Geastrumia polystigmatis, Phillipsiella atra, Microcalliopsis dipterygis and Stomiopeltis suttoniae are notoriously polyphagous and have been reported on a variety of substrates having a wide distribution and, therefore, have no interest for conservation. Four fungi occurred on both species of Dimorphandra: Pseudocercospora sp., Pseudocercosporella sp., Piricauda paraguayensis and Trichomatomyces byrsonimae. In conclusion, there is a possibility that three of the taxa showed be described as new since they are found strictly in association with D. wilsonii, Janetia sp., Byssogene sp., cf. Radulidium sp. and, are considered to be endangered fungal species.