Spencermartinsia and Vestergrenia were examined and fresh specimens of Botryosphaeriales were collected from Thailand. This material is used to provide a systematic treatment of Botryosphaeriales based on morphology and phylogeny. Two new genera, Botryobambusa and Cophinforma are introduced and compared with existing genera. Four species new to science, Auerswaldia dothiorella, A. lignicola, Botryosphaeria fusispora and Phaeobotryosphaeria eucalypti, are also described and justified. We accept 29 genera in Botryosphaeriales, with Macrovalsaria being newly placed. In the phylogenetic tree, the 114 strains of Botyrosphaeriales included in the analysis cluster into two major clades with 80 %, 96 % and 1.00 (MP, ML and BY) support, with Clade A containing the family type of Botryosphaeriaceae, and Clade B containing Phyllosticta, Saccharata and Melanops species. This group may represent Phyllostictaceae. In Clade A the taxa analyzed cluster in eight sub-clades (Clades A1-8). Clade A1 comprises three distinct subclusters corresponding to the genera Diplodia (Diplodia Clade), Neodeightonia (Neodeightonia Clade) and Lasiodiplodia (Lasiodiplodia Clade
Two new Kirschsteiniothelia species are proposed in this study; both were collected on decaying wood from Chiang Mai and Chiang Rai provinces in northern Thailand. The taxa were isolated and the morphological characters are described and illustrated. ITS, LSU and SSU combined sequence analysis showed taxa of Kirschsteiniothelia separating into three lineages: (i) K. elaterascus grouped within Morosphaeriaceae (Pleosporales); (ii) K. maritima clustered with Mytilinidion spp. as a sister group in the Mytilinidiaceae clade; and (iii) the two new Kirschsteiniothelia species, which produce Dendryphiopsis anamorphs in culture, clustered with K. aethiops (the generic type) and the anamorph D. atra. The new family Kirschsteiniotheliaceae is introduced to accommodate taxa grouping with K. aethiops. K. elaterascus is transferred to Morosphaeria (Morosphaeriaceae) and a new genus Halokirschteiniothelia is introduced to accommodate K. maritima (Mytilinidiaceae).
Australia has efficient and visible plant quarantine measures, which through various border controls and survey activities attempt to prevent the entry of unwanted pests and diseases. The ability to successfully perform this task relies heavily on determining what pathogens are present and established in Australia as well as those pathogens that are exotic and threatening. There are detailed checklists and databases of fungal plant pathogens in Australia, compiled, in part, from surveys over many years sponsored by Federal and State programmes. These checklists and databases are mostly specimen-based, which enables validation of records with reference herbarium specimens and sometimes associated cultures. Most of the identifications have been based on morphological examination. The use of molecular methods, particularly the analysis of DNA sequence data, has recently shown that several well-known and important plant pathogenic species are actually complexes of cryptic species. We provide examples of this in the important plant pathogenic genera Botryosphaeria and its anamorphs, Colletotrichum, Fusarium, Phomopsis / Diaporthe and Mycosphaerella and its anamorphs. The discovery of these cryptic species indicates that many of the fungal names in checklists need scrutiny. It is difficult, and often impossible, to extract DNA for sequence analysis from herbarium specimens in order to validate identifications that may now be considered suspect. This validation can only be done if specimens are recollected, re-isolated and subjected to DNA analysis. Where possible, herbarium specimens as well as living cultures are needed to support records. Accurate knowledge of the plant pathogens within Australia’s borders is an essential prerequisite for the effective discharge of plant quarantine activities that will prevent or delay the arrival of unwanted plant pathogens.
Isolation followed by morphological identification was the traditional basis of all earlier endophyte studies. However, the use of molecular phylogenetics has become increasingly common in the identification of fungal endophytes, and during the period of 2007-2010 there were approximately 200 publications that reported data obtained using this approach. This new methodology involves using sequence data from isolates or whole DNA from plant substrates, which are amplified using fungus-specific primers. The data obtained are compared with sequences downloaded from public databases such as GenBank and then used to construct phylogenetic trees. The major problem with this approach is that much of the sequence data in these databases has been shown to be from isolates that were incorrectly named. In some species, as much as 86% of the sequences available are not from the organism whose name has been applied to the sequence in question. The use of these GenBank sequences to identify endophytic isolates by sequence similarity simply perpetuates the problem of wrong species identification, and any lists of endophytes established by such methods are likely to be highly erroneous. It is recommended that comparisons of sequence data be made using sequences from type species, and if such sequences are not available, then the data must be treated with caution.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.