MAT genes as phylogenetic markers in the genus Lasiodiplodia

• Autor(a) principal: Domingos, Diogo João Lopes
• Data de Publicação: 2019
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10773/28350
• topic: Lasiodiplodia; Cryptic species; MAT genes; Mating strategies; Phylogeny; Systematics

Lasiodiplodia species, members of the family Botryosphaeriaceae, are pathogenic or endophytic fungi that can infect a broad range of plants, some with high economic value. This genus comprises more than 50 species described to date, based on morphological and phylogenetic analysis. In Botryosphaeriaceae, and in Lasiodiplodia, cryptic speciation is common and hybridization may occur, which makes species delimitation based on morphological characters unreliable. For this reason, species delimitation is based on the General Concordance Phylogenetic Species Recognition (GCPSR) criterium using a multi-locus phylogenetic analysis. Mating type (MAT) genes are the master regulators of sexual reproduction in fungi, they control several functions like mating combability or cellular differentiation. In this study specific sets of primers were designed for amplification and sequencing of MAT genes in all Lasiodiplodia species studied. A PCR-based mating type diagnostic assay was developed. Heterothallism was the most common state among all isolates. The potential of mating type gene sequences for species delimitation was also evaluated. These were compared with conventional molecular markers, namely, ribosomal internal transcribed spacer region (ITS) and partial sequence of the translation elongation factor 1-alpha gene (tef1-α). The results obtained show that MAT genes are able to delimit species in Lasiodiplodia with higher resolution power than the conventional molecular markers. Thereby, MAT genes represent a useful tool to differentiate cryptic species in the genus Lasiodiplodia.