Ascomycetes from freshwater habitats: Ascolacicola aquatica gen. et sp. nov., and a new species of Ascotaiwania from wood submerged in a reservoir in Hong Kong

Ascolacicola aquatica gen. et sp. nov., and Ascotaiwania mitriformis sp. nov., from decaying submerged wood collected in the Plover Cove Reservoir in Hong Kong are described and illustrated. Ascolacicola aquatica has characteristics that are common to both Ascotaiwania and Savoryella, but the anamorph is Trichocladium uniseptatum. A new genus is therefore introduced to accommodate this fungus. Ascotaiwania mitriformis sp. nov. is typical of the genus and differs from other species in having large brown fusiform ascospores with mitriform end cells. Its anamorph is an undescribed species of Monotosporella and both states of the fungus are described and illustrated.published_or_final_versio

Ascal ultrastructural study in Annulatascus hongkongensis sp. nov., a freshwater ascomycete

A new species of Annulatascus, A. hongkongenszs, is described from freshwater habitats. This species differs from other Annulatascus species as ascospores are ellipsoidal, 3-septate, verruculose and are surrounded by a thick mucilaginous sheath. Annulatascus hongkongenszs is described and illustrated with light and transmission electron micrographs, and compared with other Annulatascus species.published_or_final_versio

Vertexicola caudatus gen. et sp. nov., and a new species of Rivulicola from submerged wood in freshwater habitats

Vertexicola caudatus gen. et sp. nov., is described and illustrated from sibmerged wood collected from a creek in the Philippines and a river in Hong Kong. Vertexicola differs from other genera in the Annulatascaceae (Sordariales) in having thickwalled distoseptate ascospores and asci with a tail-like structure. The placement of Vertexicolawithin the Annulatascaceae is discussed and it is compared with other genera in this family. Rivulicola aquatica sp. nov. is also described and illustrated.published_or_final_versio

Molecular characterisation of Mycovellosiella koepki, the causal agent of yellow spot disease of sugarcane

Yellow spot of sugarcane is a fungal disease caused by Mycovellosiella koepki. Yellow spot symptoms are variable and differ in several sugarcane varieties and the existence of more than one strain of thefungus has been evoked. 29 isolates of the fungus were characterised morphologically and no significant differences were observed on the type, colour and size of the spores. Following restriction digestion of the ITS region, no significant differences were observed among isolates of the fungus and DNA sequencing of this region of the ribosomal DNA confirmed the absence of polymorphisms among the fungal strains

Pleosporales

One hundred and five generic types of Pleosporales are described and illustrated. A brief introduction and detailed history with short notes on morphology, molecular phylogeny as well as a general conclusion of each genus are provided. For those genera where the type or a representative specimen is unavailable, a brief note is given. Altogether 174 genera of Pleosporales are treated. Phaeotrichaceae as well as Kriegeriella, Zeuctomorpha and Muroia are excluded from Pleosporales. Based on the multigene phylogenetic analysis, the suborder Massarineae is emended to accommodate five families, viz. Lentitheciaceae, Massarinaceae, Montagnulaceae, Morosphaeriaceae and Trematosphaeriaceae

Ascominuta lignicola, a new loculoascomycete from submerged wood in Hong Kong

Ascominuta lignicola gen. et sp. nov. is described and illustrated based on a specimen collected on submerged wood in Hong Kong.Ascominuta lignicola is characterised by relatively small ascomata, globose, 4-spored asci, and ascospores with an elaborate sheath.Ascominuta lignicola is compared withMassarina, Mycosphaerella andWettsteinina. The placement ofAscominuta in the Ascomycetesincertae sedis is discussed

Conservation of Beclardia macrostachya

Beclardia macrostachya is a critically endangered orchid species in Mauritius. Very low level of fruit set has  been attributed to contribute to the decline in its population. Surveys carried out in the different forest regions  reveal the occurrence of this orchid at only one location, Pigeon Wood, with a present population of only 75  individuals. Biological studies at Reunion Island reveal preferential adaptation to higher altitudes, evidenced by  observed differences in fertility rates at different forest areas. Taxonomic studies using morphological characters suggest the placement of Beclardia macrostachya within a group that includes Cryptopus elatus and Aerides lawrenceae. When cultured in vitro, leaf explants developed nodular mass which failed to develop into protocorm-like bodies (PLBs). However, embryo rescue proved to be an efficient way for micropropagation of this orchid with a high regeneration capacity. Breeding programs carried out in Mauritius yielded capsules and the latter were successfully cultured to generate PLBs which would subsequently grow into plantlets

Family placement of Ascotaiwania and Ascolacicola based on DNA sequences from the large subunit rRNA gene

The family placement of Ascotaiwania and Ascolacicola have been analysed by using partial sequences of the large subunit ribosomal DNA (LSU rDNA). The 5′ end of the LSU rDNA was included in the analysis, which consisted of species from the Diaporthales, Halosphaeriales, Hypocreales, Microascales, Sordariales and Xylariales. The resulting trees indicate that Ascotaiwania is unrelated to the Annulatascaceae. A close relationship between the anamorphs of the different species of Ascotaiwania were found and they were closely related to Monotosporella setosa, the type species of Monotosporella, Based on morphological characters, production of different anamorphs, and the sequence analysis, it was found that Ascolacicola differs from Ascotaiwania, Ascolacicola was most closely related to the Sordariaceae.link_to_OA_fulltex

Molecular approaches to assessing fungal diversity in the natural environment

This paper explores the possibility of using molecular techniques to assess fungal diversity in natural environments. The use of molecular tools for the isolation and analysis of fungal DNA from different environmental substrates and matrices is examined. A comparison of techniques employed in related fields is also presented. This paper also discusses some of the limitations in using molecular tools to assess fungal diversity, as well as highlighting several distinctive advantages.link_to_OA_fulltex