A multi-locus backbone tree for Pestalotiopsis, with a polyphasic characterization of 14 new species

Abstract

Pestalotiopsis is a taxonomically confused, pathogenic and chemically creative genus requiring a critical reexamination using a multi-gene phylogeny based on ex-type and ex-epitype cultures. In this study 40 isolates of Pestalotiopsis, comprised of 28 strains collected from living and dead plant material of various host plants from China were studied by means of morphology and analysis of ITS, β-tubulin and tef1 gene sequence data. Based on molecular and morphological data we describe 14 new species (Pestalotiopsis asiatica, P. chinensis, P. chrysea, P. clavata, P. diversiseta, P. ellipsospora, P. inflexa, P. intermedia, P. linearis, P. rosea, P. saprophyta, P. umberspora, P. unicolor and P. verruculosa) and three species are epitypified (P. adusta, P. clavispora and P. foedans). Of the 10 gene regions (ACT, β-tubulin, CAL, GPDH, GS, ITS, LSU, RPB 1, SSU and tef1) utilized to resolve cryptic Pestalotiopsis species, ITS, β-tubulin and tef1 proved to be the better markers. The other gene regions were less useful due to poor success in PCR amplification and/or in their ability to resolve species boundaries. As a single gene tef1 met the requirements for an ideal candidate and functions well for species delimitation due to its better species resolution and PCR success. Although β-tubulin showed fairly good differences among species, a combination of ITS, β-tubulin and tef1 gene data gave the best resolution as compared to single gene analysis. This work provides a backbone tree for 22 ex-type/epitypified species of Pestalotiopsis and can be used in future studies of the genus.

Fungal root endophytes of tomato from Kenya and their nematode biocontrol potential

“…These results reinforce those obtained by Maharachchikumbura et al (2012) who also found that tef1α had a higher discriminatory power in comparison to ITS and ß-tubulin. Combined sequence analysis of ITS, β-tubulin and tef1α genes successfully resolved all of the species used in this study with high bootstrap support.…”

Morphology and phylogeny of Pseudorobillarda eucalypti sp. nov., from Thailand

“…Newly derived DNA sequences were deposited at GenBank (Benson et al 2010). The phylogenetic analyses were done using sequence data of select fungal species obtained from GenBank (Maharachchikumbura et al 2012. A maximum likelihood (ML) analyses was performed with a user-friendly, graphical, front-end software, raxmlGUI version 1.3 (Silvestro & Michalak 2012) using the settings of Maharachchikumbura et al (2013).…”

Two new species of Pestalotiopsis from Southern China

“…PCR was performed with the 25 μL reaction system consisting of 19.75 μL of double distilled water, 2.5 μL of 10× Taq buffer with MgCl 2 , 0.5 μL of dNTP (10 mM each), 0.5 μL of each primer (10 μM), 0.25 μL Taq DNA polymerase (5 U/μl), and 1.0 μL of DNA template. The thermal cycling program followed Maharachchikumbura et al (2012). The DNA sequences of ITS, beta-tubulin and tef1 regions generated in this study were submitted to GenBank.…”

“…The Kishino-Hasegawa tests (Kishino & Hasegawa 1989) were performed in order to determine whether the trees inferred under different optimality criteria were significantly different. DNA sequences from our Pestalotiopsis isolates were com pared with those that originated from Maharachchikumbura et al (2012), with Seiridium sp. (SD096) as outgroup.…”