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The genus Calonectria includes many important plant pathogens with a wide global distribution. In order to better understand the reproductive biology of these fungi, we characterised the structure of the mating type locus and flanking genes using the genome sequences for seven Calonectria species. Primers to amplify the mating type genes in other species were also developed. PCR amplification of the mating type genes and multi-gene phylogenetic analyses were used to investigate the mating strategies and evolution of mating type in a collection of 70 Calonectria species residing in 10 Calonectria species complexes. Results showed that the organisation of the MAT locus and flanking genes is conserved. In heterothallic species, a novel MAT gene, MAT1-2-12 was identified in the MAT1-2 idiomorph; the MAT1-1 idiomorph, in most cases, contained the MAT1-1-3 gene. Neither MAT1-1-3 nor MAT1-2-12 was found in homothallic Calonectria (Ca.) hongkongensis, Ca. lateralis, Ca. pseudoturangicola and Ca. turangicola. Four different homothallic MAT locus gene arrangements were observed. Ancestral state reconstruction analysis provided evidence that the homothallic state was basal in Calonectria and this evolved from a heterothallic ancestor.

Calonectria represents a genus of phytopathogenic ascomycetous fungi with a worldwide distribution. In recent years, there has been an increase in the number of taxonomic studies on these fungi. Currently, there are 169 described species of Calonectria based on comparisons of DNA sequence data, combined with morphological characteristics. However, for some of these species, the sequence data utilised at the time of their description were relatively limited. This has justified an urgent need to reconsider the species boundaries for Calonectria based on robust genus-wide phylogenetic analyses. In this study, we utilised 240 available isolates including the ex-types of 128 Calonectria species, and re-sequenced eight gene regions (act, cmdA, his3, ITS, LSU, rpb2, tef1 and tub2) for them. Sequences for 44 Calonectria species, for which cultures could not be obtained, were downloaded from GenBank. DNA sequence data of all the 169 Calonectria species were then used to determine their phylogenetic relationships. As a consequence, 51 species were reduced to synonymy, two new species were identified, and the name Ca. lauri was validated. This resulted in the acceptance of 120 clearly defined Calonectria spp. The overall data revealed that the genus includes 11 species complexes, distributed across the Prolate and Sphaero-Naviculate Groups known to divide Calonectria. The results also made it possible to develop a robust set of DNA barcodes for Calonectria spp. To accomplish this goal, we evaluated the outcomes of each of the eight candidate DNA barcodes for the genus, as well as for each of the 11 species complexes. No single gene region provided a clear identity for all Calonectria species. Sequences of the tef1 and tub2 genes were the most reliable markers; those for the cmdA, his3, rpb2 and act gene regions also provided a relatively effective resolution for Calonectria spp., while the ITS and LSU failed to produce useful barcodes for species discrimination. At the species

The Botryosphaeriaceae is a species-rich family that includes pathogens of a wide variety of plants, including species of Eucalyptus. Recently, during disease surveys in China, diseased samples associated with species of Botryosphaeriaceae were collected from plantation Eucalyptus and other plants, including Cunninghamina lanceolata, Dimocarpus longan, Melastoma sanguineum and Phoenix hanceana, which were growing adjacent to Eucalyptus. In addition, few samples from Araucaria cunninghamii and Cedrus deodara in two gardens were also included in this study. Disease symptoms observed mainly included stem canker, shoot and twig blight. In this study, 105 isolates of Botryosphaeriaceae were collected from

SCOPUS: ar.j, info:eu-repo/semantics/published

The sheet area is situated in the Eastern Goldfields province of the Archaean Yilgarn craton. It can be subdivided into the Malcolm, Murrin and Laverton greenstones; rock types include ultramafic and mafic, felsic volcanic and sedimentary rocks and granitoids, deformed in several phases. Gold has been produced from all the major greenstone areas, with mining centred on the Yilgangi, Yarri, Edjudina, Patricia, Yerilla, Yundamindera, Eucalytus-Pykes Hollow, Linden, Mount Celia and Sunrise Dam areas. A number of low-grade, laterite-hosted nickel deposits have been identified, by-product silver has been recovered, there are traces of copper in several gold mines and gem chrysoprase has been produced from several small open pits., The sheet area is situated in the Eastern Goldfields province of the Archaean Yilgarn craton. It can be subdivided into the Malcolm, Murrin and Laverton greenstones; rock types include ultramafic and mafic, felsic volcanic and sedimentary rocks and granitoids, deformed in several phases. Gold has been produced from all the major greenstone areas, with mining centred on the Yilgangi, Yarri, Edjudina, Patricia, Yerilla, Yundamindera, Eucalytus-Pykes Hollow, Linden, Mount Celia and Sunrise Dam areas. A number of low-grade, laterite-hosted nickel deposits have been identified, by-product silver has been recovered, there are traces of copper in several gold mines and gem chrysoprase has been produced from several small open pits.

The sheet covers a poorly exposed, repeatedly deformed granite-greenstone terrain in which an older, mafic-dominated greenstone succession and a younger greenstone succession dominated by felsic volcanic and clastic sedimentary rocks are in faulted or intrusive contact with mainly younger granitoids of dominantly monzogranitic composition. All greenstones have been metamorphosed at low to high temperatures, but none have been deeply buried. Although gold has been produced from a number of localities, no large deposits have been discovered and no economic concentrations of base metals have ever been identified despite extensive exploration for volcanogenic massive sulphides., The sheet covers a poorly exposed, repeatedly deformed granite-greenstone terrain in which an older, mafic-dominated greenstone succession and a younger greenstone succession dominated by felsic volcanic and clastic sedimentary rocks are in faulted or intrusive contact with mainly younger granitoids of dominantly monzogranitic composition. All greenstones have been metamorphosed at low to high temperatures, but none have been deeply buried. Although gold has been produced from a number of localities, no large deposits have been discovered and no economic concentrations of base metals have ever been identified despite extensive exploration for volcanogenic massive sulphides.

Geological mapping and exploration drilling results showed widespread but poorly exposed komatiites in the southern part of the Sandstone greenstone belt, representing the most significant occurrence of komatiites in the north-central Yilgarn craton. Relict olivine-cumulate and less common olivine-spinifex textures are preserved in spite of serpentinisation and talc-carbonate alteration. Whole-rock geochemistry indicates the presence of Al-depleted and Al-undepleted komatiites, both of which are also found in the Forrestania greenstone belt of the south-central Yilgarn craton. The recognition of widespread komatiites has important implications for the discovery of komatiite-hosted nickel sulphide deposits, as stratiform accumulations of Fe-Ni-Cu sulphides may have formed in embayments or troughs at the base of the komatiite lava flows after sulphur contamination. Many samples have favourable chemistry with more than 20% MgO and more than 1 000 ppm Ni, the range commonly observed for mineralized komatiites., Geological mapping and exploration drilling results showed widespread but poorly exposed komatiites in the southern part of the Sandstone greenstone belt, representing the most significant occurrence of komatiites in the north-central Yilgarn craton. Relict olivine-cumulate and less common olivine-spinifex textures are preserved in spite of serpentinisation and talc-carbonate alteration. Whole-rock geochemistry indicates the presence of Al-depleted and Al-undepleted komatiites, both of which are also found in the Forrestania greenstone belt of the south-central Yilgarn craton. The recognition of widespread komatiites has important implications for the discovery of komatiite-hosted nickel sulphide deposits, as stratiform accumulations of Fe-Ni-Cu sulphides may have formed in embayments or troughs at the base of the komatiite lava flows after sulphur contamination. Many samples have favourable chemistry with more than 20% MgO and more than 1 000 ppm Ni, the range commonly observed for mineralized komatiites.