Strategies for rapid assessment of fungal diversity

The problems of estimating fungal diversity are considerable, due especially to the large numbers of species even in small study sites, only a small proportion of which are adequately characterized, and the lack of trained staff and appropriate identification manuals. These difficulties are multiplied in the tropics. Strategies for providing preliminary assessments of fungal diversity which can be carried out within short time-frames are discussed, which will allow initial site valuations to be made for conservation purposes. The necessity of identifying all species discovered is considered, and the need emphasized for strictly defined sampling protocols which allow proper comparison between sites. The advantages and disadvantages of preliminary diversity analyses involving different taxonomic and ecological groups, fungus/plant associations, spatial sampling, soil and litter analysis, molecular methods and indirect assessment are considered.     

Heterobasidiomycetous fungi from Aegean Islands (Greece): New annotated records for a neglected group

As part of an inventory of macrofungi in selected islands of the Aegean Archipelago (Greece), 18 species of heterobasidiomycetes (phylum Basidiomycota) belonging to the orders Auriculariales, Cantharellales, Dacrymycetales and Tremellales were collected and identified from the islands of Agios Efstratios, Amorgos, Andros, Crete, Ikaria, Naxos and Nisyros. Among the heterobasidiomycetous fungi collected, Ceratobasidium cornigerum, Dacrymyces lacrymalis, Exidiopsis effusa, E. galzinii, Thanatephorus amygdalisporus, Tremella aurantia, Tulasnella pallida and T. pruinosa constitute first national records, while the genera Ceratobasidium, Thanatephorus and Tulasnella are reported for the first time in Greece. All species are listed with information on their hosts/substrates and occurrence in the investigated islands, while the most interesting records are described, illustrated, and critically discussed in the light of existing taxonomic and distribution data.     

Taxonomic reconsideration of Tricholoma foliicola (Agaricales,Basidiomycota) based on basidiomata morphology,living culture characteristics,and phylogenetic analyses

Tricholoma foliicola was taxonomically reevaluated based on analyses of the holotype and newly collected materials. Basidiospores of T. foliicola were irregularly ellipsoid, showing a cyanophilic reaction with or without tubercles. Phylogenetic analyses of the internal transcribed spacer (ITS) and large subunit 28S regions of the fungal nuclear ribosomal RNA gene demonstrated that T. foliicola is a species of Gerhardtia characterized by irregularly shaped basidiospores. Thus, we transferred this species to Gerhardtia foliicola comb. nov. Cultured mycelia of G. foliicola on malt extract agar medium produced cystidia covered with granules and abundant thallic conidia (arthroconidia), with both schizolytic and rhexolytic secession.     

The interspecific competition presents greater nutrient facilitation compared with intraspecific competition through AM fungi interacting with litter for two host plants in karst soil

AM 真菌和枯落物互作下两种喀斯特植物种间竞争较种内竞争更能促进植物养分利用 枯落物是植物养分获取和土壤养分转化的关键载体。丛枝菌根(Arbuscular mycorrhizae, AM)对植物养分摄取的影响已被广泛认知。然而，在养分亏缺的喀斯特生境中，不同竞争方式的植物如何通过AM真菌和枯落物利用养分尚不清楚。本研究对两种喀斯特适生植物构树(Broussonetia papyrifera)和云贵鹅耳枥(Carpinus pubescens)进行种内竞争和种  间竞争种植处理，并通过幼套球 囊霉(Glomus etunicatum)接种或不接种处理，以及土壤中添加或不添加两物种叶片混合枯落物处理，测定了植物生物量以及氮、磷、钾浓度等指标，研究植物的生长和养分利用。研究结果表明，AM真菌对两种植物养分摄取影响不同，AM真菌显著提高了种内和种间竞争下构树的养分摄取量，但降低了云贵鹅耳枥的养分摄取量。种间竞争下接种AM真菌，枯落物添加促进了云贵鹅耳枥对氮的摄取，抑制了构树对氮的摄取。接种AM真菌和添加枯落物条件下，种间竞争的构树对氮、磷和钾的摄取量及云贵鹅耳枥对氮的摄取量均高于种内竞争；种间竞争下两物种养分竞争力呈现明显差异，即构树对磷和钾养分竞争力显著提高，对氮则不显著；云贵鹅耳枥仅对钾的养分竞争力显著降低，对氮和磷则无显著影响。这些结果说明，在AM真菌与枯落物相互作用下，两种喀斯特植物种间竞争较种内竞争更能促进植物养分利用。     

Effects of Inositol Deficiency on Respiratory and Fermentative Activities of Inositol-exacting Yeast,Schizosaccharomyces pombe

Inositol deficiency of Schizosaccharomyces pombe did not induce significant change of contents of various cellular components except for phospholipids and inositol. The most remarkable decrease in inositol content by the deficiency occurred in the mitochondrial fraction. Electronmicroscopic observation of the inositol-deficient cells of Sch. pombe showed no remarkable thickening of cell wall as occurred in the inositol-exacting mutant of Saccharomyces cerevisiae Strain A–21–20.

Marked loss of fermentative activity under the aerobic condition was caused from inositol deficiency without significant change of activities of respiration and anaerobic fermentation. This seemed to indicate elevated regulatory control of the fermentative activity by oxygen in the inositol-deficient Sch. pombe.

Phosphorylative activities of intact cells and the isolated mitochondria coupled with oxidation was also remarkably suppressed by inositol deficiency.     

Laboratory evaluation of a new strain CCM 8367 of Isaria fumosorosea (syn. Paecilomyces fumosoroseus) on Spodoptera littoralis (Boisd.)

Laboratory experiments were conducted to assess the efficiency of the new strain CCM 8367 of Isaria fumosorosea on different stages of the Egyptian cotton leafworm, Spodoptera littoralis (Boisd.), including soil treatments with pre-pupal and pupal stages. Treatments of larval instars showed a high susceptibility with 3rd, 5th and last instars to suspension of this fungus with concentration 5?×?10⁷ spores/ml. Larval mortality was over 90%. There were no significant differences (P?=?0.7929, F?=?0.2346) between instar treatments. The commercial fungus, PreFeRal® strain Apopka 97 of I. fumosorosea, which was used in comparison with this new strain caused mortality rates of between 63.33 and 90%. Statistically, differences between the effects of CCM 8367 strain and Apopka 97 were highly significant on the last instar (P?=?0.0064, F?=?6.479) and extremely significant on the 3rd instar (P?<?0.0001, F?=?13.29). No significant differences were recorded between the two strains on the 5th instar (P?=?0.0597, F?=?3.233). Fungal treatments with the late stage insects (end of the last instar or pupal stage) in soil yielded interesting results: the mortality rate on end of final instar larvae was 16.66% when treated with Apopka 97 and 83.33% when treated with CCM 8367. Soil containing pupae of S. littoralis that were inoculated with CCM8367 resulted in a high number of malformed adults, and the mortality rate was 64.52% (32.27% of malformed adults died and 32.25% of pupae fully infected by fungus). Only 3.23% of samples produced morphologically normal adults in this test. The results conclude that the strain of I. fumosorosea CCM 8367 has strong insecticidal effects on S. littoralis and has the potential to be implemented as a novel biocontrol agent.     

Species confirmation of fungal isolates by molecular analysis

Traditional taxonomy of hyphomycetes has been based on conidial morphology and development. In order to confirm species level for the detection and identification of the entomopathogenic fungus, we analysed the species-specific fingerprints to investigate molecular characteristics within isolates of six species and to resolve morphologically atypical isolates. The extent of fingerprint profile observed by RAPD was sufficient to confirm the species level of all the isolates. The genetic similarity among morphologically identified isolates of each species was considerably higher, allowing us to conclude that all the isolates are of same species. These results establish a molecular framework for further taxonomic, phylogenetic and comparative biological investigations.     

Pan-cancer analyses reveal cancer-type-specific fungal ecologies and bacteriome interactions

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