Epitypification, characterization and phylogenetic positioning of Pseudobeltrania cedrelae, the causal agent of pseudobeltrania spot on Cedrela fissilis

Abstract

Summary The fungus Pseudobeltrania cedrelae, the type species of the genus, is the causal agent of an important leaf spot in seedlings and adult plant of cedar (Cedrela fissilis). Due to the contradictory phylogenetic position of the genus Pseudobeltrania, epitypification of P. cedrelae was carried out based on a culture obtained from the same locality and host of the original type. Samples were collected, and 10 isolates of P. cedrelae associated with lesions on cedar leaflets were obtained. For morphological characterization, conidia, conidiophores, conidiogeneous cells, conidiogeneous loci and basal cells were taken both from the fungus obtained from leaf lesions and from that obtained in slide culture. Mycelial growth rates and sporulation were evaluated in six different culture media. For molecular phylogeny, maximum parsimony analyses were performed from the ITS and 28S sequences of the isolates. Both the morphological characteristics of the fungal structures obtained from symptomatic leaves and the slide culture technique presented variations. In foliar lesions, isolates presented the same morphological characteristics as the type material. Mycelial growth rate and sporulation of P. cedrelae were greatest on malt extract agar and V8 juice agar. Pseudobeltrania cedrelae was pathogenic when inoculated into healthy cedar plants. According to the phylogenetic tree, isolates grouped in the same clade, but in a distinct clade of Pseudobeltrania ocoteae. The results suggested that P. ocoteae belongs to the genus Hemibeltrania. This paper presents new information on P. cedrelae that contributes to clarifying the phylogeny of the Beltraniaceae.

A higher altitude enclave of humid forest in the semi-arid of Brazil holds a diversity of conidial fungi on leaf-litter

“…Beltrania rhombica (Table 2) is considered cosmopolitan and commonly found associated with leaf litter in taxonomic studies, but also in diversity and succession studies of fungi in Brazil (Maia 1983;Castro et al 2012;Magalhães et al 2013), Japan (Milagres et al 2018), India (Pirozynski & Patil 1970), Cuba (Delgado-Rodriguez et al 2002), and United States (Heredia-Abarca 1994. Likewise, Wiesneriomyces laurinus has a cosmopolitan distribution and the taxon is reported in studies in Brazil (Gusmão & Grandi 1997;Silva & Grandi 2008), Australia (Paulus et al 2007), Myanmar (Thaung 2008), and Canada (Pratibha et al 2015), among others.…”