Evolution of the Ergot Alkaloid Biosynthetic Gene Cluster Results in Divergent Mycotoxin Profiles in <i>Claviceps purpurea</i> Sclerotia

Research into ergot alkaloid production in major cereal cash crops is crucial for furthering our understanding of the potential toxicological impacts of Claviceps purpurea upon Canadian agriculture and to ensure consumer safety. An untargeted metabolomics approach profiling extracts of C. purpurea sclerotia from four different grain crops separated the C. purpurea strains into two distinct metabolomic classes based on ergot alkaloid content. Variances in C. purpurea alkaloid profiles were correlated to genetic differences within the lpsA gene of the ergot alkaloid biosynthetic gene cluster from previously published genomes and from newly sequenced, long-read genome assemblies of Canadian strains. Based on gene cluster composition and unique polymorphisms, we hypothesize that the alkaloid content of C. purpurea sclerotia is currently undergoing adaptation. The patterns of lpsA gene diversity described in this small subset of Canadian strains provides a remarkable framework for understanding accelerated evolution of ergot alkaloid production in Claviceps purpurea

Trichoderma down under: Species diversity and occurrence of Trichoderma in New Zealand

This is the first comprehensive survey of the species diversity of Trichoderma for a region within the temperate Southern Hemisphere. New Zealand makes an ideal target for such a survey because of the extensive historical collections of this genus from both native and human-modified ecosystems. From the 320 Trichoderma strains sequenced for the translation elongation factor-1α (tef1α) gene, in addition to the names associated with voucher specimens at the New Zealand Fungarium (PDD, Landcare Research), we recognise 71 Trichoderma species as present in New Zealand. Thirty-two species are reported for the first time from New Zealand and 14 of these appear to represent undescribed taxa. The New Zealand species are positioned across most Trichoderma clades, with terminal lineages related to T. viride, T. koningii and T. harzianum well represented. Of the 14 undescribed species, Trichoderma sp. “atroviride B”, a sister species to T. atroviride s.s., was the most commonly recovered species. Records of several species known only from fungarium specimens could not be confirmed by DNA analysis. Populations of Trichoderma in New Zealand are likely to represent a mixture of ancient indigenous lineages, more recent natural introductions, and species introduced as a result of human-mediated dispersal. Twenty-three Trichoderma species have been reported only from New Zealand or other Southern Hemisphere locations. The diversity of Trichoderma species in New Zealand, their phylogenetic relationships, distribution, ecology, and possible origins are discussed in this paper

Nine draft genome sequences of Claviceps purpurea s.lat., including C. arundinis, C. humidiphila, and C. cf. spartinae, pseudomolecules for the pitch canker pathogen Fusarium circinatum, draft genome of Davidsoniella eucalypti, Grosmannia galeiformis, Quambalaria eucalypti, and Teratosphaeria destructans

CITATION: Wingfield, B. D., et al. 2018. Nine draft genome sequences of Claviceps purpurea s.lat., including C. arundinis, C. humidiphila, and C. cf. spartinae, pseudomolecules for the pitch canker pathogen Fusarium circinatum, draft genome of Davidsoniella eucalypti, Grosmannia galeiformis, Quambalaria eucalypti, and Teratosphaeria destructans. IMA Fungus, 9(2):401-418, doi:10.5598/imafungus.2018.09.02.10.The original publication is available at https://imafungus.biomedcentral.comThis genome announcement includes draft genomes from Claviceps purpurea s.lat., including C. arundinis, C. humidiphila and C. cf. spartinae. The draft genomes of Davidsoniella eucalypti, Quambalaria eucalypti and Teratosphaeria destructans, all three important eucalyptus pathogens, are presented. The insect associate Grosmannia galeiformis is also described. The pine pathogen genome of Fusarium circinatum has been assembled into pseudomolecules, based on additional sequence data and by harnessing the known synteny within the Fusarium fujikuroi species complex. This new assembly of the F. circinatum genome provides 12 pseudomolecules that correspond to the haploid chromosome number of F. circinatum. These are comparable to other chromosomal assemblies within the FFSC and will enable more robust genomic comparisons within this species complex.https://imafungus.biomedcentral.com/articles/10.5598/imafungus.2018.09.02.10Publisher's versio