1,720,988 research outputs found
Effect of summer soil moisture and temperature on the vertical distribution of Tuber magnatum mycelium in soil
Full text linkTuber magnatum, the Italian white truffle, is the world’s most valuable truffle. Despite the economic importance, its biology and ecology are largely unexplored. This gap of knowledge makes difficult to find reliable methods for its cultivation and to protect and increase the production of the natural productive areas. In this study, the vertical distribution of T. magnatum mycelium in productive soil patches was evaluated using a quantitative PCR (qPCR) approach. Data were then used to develop for the first time a simulation model to predict the mycelial dynamics of T. magnatum at varying soil temperatures and moisture. T. magnatum mycelium was abundant up to 30-cm depth, while the model determined the optimal temperature (20 °C) and water potential (~ 0 kPa) for growth of T. magnatum mycelium in soil. Such information could be useful to establish proper irrigation scheduling and to enhance the management of T. magnatum sites, for increasing mycelial growth and fruiting body production
Viability and infectivity of Tuber borchii after cryopreservation
No full textBACKGROUND: Truffles (Tuber spp.) are the most precious ectomycorrhizal edible mushrooms whose biodiversity is seriously endangered. OBJECTIVE: To develop a protocol for cryopreservation of Tuber spp. mycelia using T. borchii as a model species, verifying whether conservation in liquid nitrogen may affect viability, growth rate, hyphal morphology and infectivity. MATERIALS AND METHODS: Cryopreservation was performed using sorbitol, sucrose and DMSO as cryoprotectants. The morphological parameters analyzed were: hyphal diameter, septal distance and hyphal growth unit. Cryopreserved mycelium infectivity was assessed by inoculating Quercus robur seedlings. RESULTS: In T. borchii cryopreserved mycelium, the lag-phase lasted for 6-42 days but no differences in growth curve evolution, growth rate and hyphal morphology were observed except for hyphal growth unit. No differences in mycorrhizal colonization were observed between the seedlings inoculated with non-cryopreserved and cryopreserved mycelium. CONCLUSION: The established protocol is suitable for long-term conservation of Tuber mycelium and opens up the possibility of creating a Tuber spp. germplasm bank to preserve truffle diversity
Ecological and genetic advances in the cultivation of Tuber Spp
No full textRecent advances on the ecology and genetics of true truffles (Tuber spp.) are reported and their impact on truffle cultivation is discussed. New insights have been gained on truffle soil ecology and interrelationships of truffles with associated microorganisms in the soil. For instance, some bacteria seem to play a key role in truffle fruiting body formation and maturation. However, the most important advance in truffle genetics over the past 20 years has been the sequencing of the Tuber melanosporum genome and the discovery that truffles, like other Pezizalean fungi, are heterothallic. This finding has had a significant impact on research on truffles and many studies have been devoted to better understanding the distribution of the mating types in soil in natural and cultivated truffià ̈res. The characterization of the mating type idiomorphs of several Tuber species has led to the possibility of selecting mycelial strains for truffle cultivation in particular sites
Biodiversità fungina in boschi vetusti di faggio e castagno del Parco Nazionale del Cilento e Vallo di Diano: primi risultati.
No full textEcological and genetic advances in the cultivation of Tuber Spp
No full textRecent advances on the ecology and genetics of true truffles (Tuber spp.) are reported and their impact on truffle cultivation is discussed. New insights have been gained on truffle soil ecology and interrelationships of truffles with associated microorganisms in the soil. For instance, some bacteria seem to play a key role in truffle fruiting body formation and maturation. However, the most important advance in truffle genetics over the past 20 years has been the sequencing of the Tuber melanosporum genome and the discovery that truffles, like other Pezizalean fungi, are heterothallic. This finding has had a significant impact on research on truffles and many studies have been devoted to better understanding the distribution of the mating types in soil in natural and cultivated truffià ̈res. The characterization of the mating type idiomorphs of several Tuber species has led to the possibility of selecting mycelial strains for truffle cultivation in particular sites
Ultra-low freezing to preserve the lingzhi or reishi medicinal mushroom Ganoderma lucidum (Agaricomycetes)
No full textGanoderma lucidum (Curtis) P. Karst., commonly used in traditional Chinese medicine, is characterized by strong genetic and phenotypic variability that reflects its active components. To preserve such a source of pharmacologically active metabolites, specimens must be collected from different geographic regions and their genetic integrity ensured during storage. To this aim, we tested the effect of ultra-low freezing (ULF) at −120°C on the vitality, mycelial growth rate, and fruiting ability of 3 Italian strains of G. lucidum. Results showed that all strains reacted positively to ULF, demonstrating an ability to recover after 3 months of storage without morphological or physiological changes occurring, regardless of treatment. The successful storage of G. lucidum at −120°C opens up the possibility to create a germplasm bank to collect strains of this medicinal fungus from throughout Europe, thereby contributing to the maintenance of its diversity
Biocontrol of Rhizoctonia solani disease and biostimulant effect by microbial products on bean plants
Full text linkMicrobial products containing a mixture of fungi and bacteria (EM Bokashi® 2-fi and EM-5 Sutociu® characterised by plant biostimulant activity), Trichoderma harzianum T22 (biofungicide) and the antagonist fungus Trichoderma sp. TJ40 were tested for efficacy against R. solani disease and for their biostimulant effects on bean plants, in growth chamber experiments, and for their direct effect on the pathogen growth, through in vitro experiments. In growth chamber experiments, EM-5 Sutociu was applied to seed (Sut/Se), substrate (Sut/S) and leaf (Sut/L) many times, EM Bokashi 2-fi to substrare (Bok/S) once and combined with Sut, T22 and TJ40 were applied once to substrate. The pathogen was inoculated to substrate at seeding time (first experiment) or at seedling phase (second experiment). Under our experimental conditions, Bok/S+Sut/S+Sut/L, Sut/S+Sut/L, Sut/Se+Sut/S+Sut/L and T22, in the first experiment, and all treatments, with the exception of Bok/S applied alone in the second experiment, gave significantly disease severity reduction and increase of dry weight and leaf area with respect to the infected control. The TJ40 treatment reduced both disease incidence and disease severity only in the second experiment. In the experiment on the biostimulant effect, T22, Bok/S+Sut/S+Sut/L, Sut/S+Sut/L and Sut/Se+Sut/S+Sut/L showed significantly increases of both dry weight and leaf area. The direct effect of the treatment with T22, TJ40, Bok and Sut on R. solani growth in vitro was studied with two methods, submerged colony (SC) and well diffusion (WD) assays. The pathogen growth was completely inhibited by Trichoderma T22 in both assays, by Trichoderma TJ40 in a range of 80-50 % in SD assay, and 50-30 % in WD assay and slightly inhibited or not inhibited by Bok and Sut
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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