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Eucalyptus spp. are widely planted in Colombia as an important component of a growing paper and pulp industry. Leaf and shoot blight caused by Calonectria spp. was one of the first disease problems to emerge in these plantations. A survey of Eucalyptus plantations in four forestry regions of Colombia during 2016 resulted in a large number of Calonectria isolates from soil samples collected in the understories of trees having symptoms of Calonectria leaf and shoot blight. The aim of this study was to identify and resolve the phylogenetic relationships for these isolates using DNA sequence comparisons of six gene regions as well as morphological characters. From a collection of 107 isolates, seven Calonectria species residing in three species complexes were identified. Two of these represented undescribed species, namely C. exiguispora sp. nov. and C. guahibo sp. nov. Calonectria parvispora and C. spathulata were the most commonly isolated species, each of which accounted for approximately 30% of the isolates. The results suggest that Colombia has a wide diversity of Calonectria spp. and that these could challenge Eucalyptus plantation forestry in the future. [ABSTRACT FROM AUTHOR]

Huntiella species are wood-infecting, filamentous ascomycetes that occur in fresh wounds on a wide variety of tree species. These fungi are mainly known as saprobes although some have been associated with disease symptoms. Six fungal isolates with typical culture characteristics of Huntiella spp. were collected from wounds on native forest trees in Greece and South Africa. The aim of this study was to identify these isolates, using morphological characters and multigene phylogenies of the rRNA internal transcribed spacer (ITS) region, portions of the ß-tubulin (BT1) and translation elongation factor 1a (TEF-1a) genes. The mating strategies of these fungi were also determined through PCR amplification of mating type genes. The study revealed two new species; one from Platanus orientalis in Greece and one from Colophospermum mopane and Senegalia nigrescens in South Africa. These novel taxa have been provided with the names, H. hellenica sp. nov. and H. krugeri sp. nov., respectively. The former species was found to have a homothallic and the latter a heterothallic mating system. [ABSTRACT FROM AUTHOR]

The Leptographium olivacea complex encompasses species in the broadly defined genus Leptographium (Ophiostomatales, Ascomycota) that are generally characterized by synnematous conidiophores. Most species of the complex are associates of conifer-infesting bark beetles in Europe and North America. The aims of this study were to reconsider the delineation of known species, and to confirm the identity of several additional isolates resembling L. olivacea that have emerged from recent surveys in China, Finland, Poland, Russia, and Spain. Phylogenetic analyses of sequence data for five loci (ACT, TUB, CAL, ITS2-LSU, and TEF-1α) distinguished 14 species within the complex. These included eight known species (L. cucullatum, L. davidsonii, L. erubescens, L. francke-grosmanniae, L. olivaceum, L. olivaceapini, L. sagmatosporum, and L. vescum) and six new species (herein described as L. breviuscapum, L. conplurium, L. pseudoalbum, L. rhizoidum, L. sylvestris, and L. xiningense). New combinations are provided for L. cucullatum, L. davidsonii, L. erubescens, L. olivaceum, L. olivaceapini, L. sagmatosporum and L. vescum. New Typifications: Lectotypes are designated for L. olivaceum, L. erubescens and L. sagmatosporum. Epitypes were designated for L. olivaceapini and L. sagmatosporum. In addition to phylogenetic separation, the synnematous asexual states and ascomata with almost cylindrical necks and prominent ostiolar hyphae, distinguish the L. olivaceum complex from others in Leptographium. [ABSTRACT FROM AUTHOR]

Trees in the genus Vachellia (previously Acacia) are commonly infected by the gall-inducing rusts Ravenelia macowaniana and R. evansii. Rust galls bearing aecial infections and relating uredinial and telial infections on the leaves of nine Vachellia species not previously recorded to be infected by Ravenelia spp. have recently been collected in South Africa. The rust fungi causing these infections were characterised using molecular phylogenetic analyses of DNA sequence data of the LSU and ITS rDNA regions as well as morphological examinations. The host range of R. macowaniana and R. evansii was thus re-assessed and extended from four to nine species and from one to three species, respectively. Application of Principal Component Analyses (PCA) of telial morphological characters provided evidence of an effect of the host species on the teliospore morphology in R. evansii, but only minor effects in R. macowaniana. A novel gall-inducing Ravenelia sp. closely related to R. macowaniana, was found on Vachellia xanthophloea and it is described here as R. xanthophloeae. [ABSTRACT FROM AUTHOR]

The Ophiostomatales is an Ascomycete order of fungi that accommodates several tree pathogens and many species that degrade wood. These fungi are commonly vectored by Scolytine bark and ambrosia beetles. In recent years it has also been shown that hyperphoretic mites on these beetles can vector some Ophiostomatales. Little is known regarding the Ophiostomatales in China and we have consequently explored the diversity of these fungi associated with conifer-infesting beetles and mites in Yunnan province. Galleries and beetles were collected for 17 beetle species, while 13 mite species were obtained from six of these beetle species. Collectively, 340 fungal isolates were obtained, 45 from beetles, 184 from mites, 56 from galleries and 55 isolates where the specific niche was not clear. DNA sequences for five gene regions (ITS, LSU, BT, EF, and CAL) were determined for fungal isolates representing different morphological groups. Phylogenetic analyses confirmed the presence of 19 fungal taxa, including five novel species described here as Ophiostoma acarorum sp. nov., Ophiostoma brevipilosi sp. nov., Graphilbum kesiyae sp. nov., Graphilbum puerense sp. nov., and Leptographium ningerense sp. nov. Ophiostoma ips was the most frequently isolated species, representing approximately 31% of all isolates. Six of 19 taxa were present on mites, beetles and in the galleries of the beetles, while three species were found on mites and galleries. Two species were found only on mites and one species only on a beetle. Although the numbers of beetles and mites were insufficient to provide statistical inferences, this study confirmed that mites are important vectors of the Ophiostomatales in China. We hypothesize that these mites are most likely responsible for horizontal transfer of fungal species between galleries of different beetle species. The fact that half of the fungal species found were new to science, suggests that the forests of east Asia include many undescribed Ophiostomatales yet to be discovered. [ABSTRACT FROM AUTHOR]