Phylogenetic placement of Tritirachium strains from the URM culture collection originally founded by Augusto Chaves Batista (1916–1967) in Brazil, and the description of T. batistae sp. nov.

Abstract

Twenty-seven Tritirachium strains were present in the URM culture collection originally founded in Brazil by Augusto Chaves Batista. Fifteen freshly-prepared cultures were obtained from these original strains preserved under mineral oil. DNA was extracted for analysing phylogenetic relationships using the sequence information available from Tritirachium type materials and reference strains. Phylogenetic analysis using the internal transcribed spacer (ITS) ribosomal DNA sequences revealed that eight of these strains belong to the same clade as of T. oryzae and that the four other strains belong to the same clade as of T. candoliense. The strain URM 38, which was previously identified as “T. brumptii”, appeared to exist as a single lineage, related to T. roseum and T. candoliense. Based on morphological features and multi-locus phylogenetic analysis, including the analyses of ITS and LSU rDNA, and rpb2 sequences, we propose that URM 38 belongs to the new species T. batistae. This novel species exhibited velutinous to cottony colonies of varying colour, septate hyphae without clamp connections, conidiophores reduced to conidiogenous cells, conidiogenous cells with a distinct sympodial rachis, and single-cell conidia that was globose to subglobose, obovoid, smooth, and hyaline. The morphological features of species accepted in Tritirachium are included in this study.