Habitat models of wood-inhabiting fungi along a decay gradient of Norway spruce logs

Information on the habitat requirements of wood-inhabiting fungi is needed to understand the factors that affect their diversity. We applied culture-free DNA extraction and 454-pyrosequencing to study the mycobiota of decaying Norway spruce (Picea abies) logs in five unmanaged boreal forests. Fungal habitat preferences in respect of wood density gradient were then estimated with generalized additive mixed models. Fungal diversity and wood density were inversely related, i.e., OTU richness generally increased as the log became increasingly decomposed. White-rot fungi (e.g., Phellinus nigrolimitatus) and members of Hyphodontia did not show a clear response to the wood-density gradient, whereas abundance of Phellinus viticola and brown-rot fungi (e.g., Fomitopsis pinicola, Antrodia serialis, Coniophora olivaceae) peaked during intermediate decay and mycorrhizal fungi (e.g., Piloderma, Tylospora, Russula) increased in the later stages. This information on fungal habitat requirements facilitates the development of management practices that preserve fungal diversity in managed forests.201

Impact of hexamine addition to a nitrite-based additive on fermentation quality, Clostridia and Saccharomyces cerevisiae in a white lupin-wheat silage

BACKGROUND Nitrite and hexamine are used as silage additives because of their adverse effects on Clostridia and Clostridia spores. The effect of sodium nitrite and sodium nitrite/hexamine mixtures on silage quality was investigated. A white lupin-wheat mixture was treated with sodium nitrite (NaHe0) (900 g t(-1) forage), or mixtures of sodium nitrite (900 g t(-1)) and hexamine. The application rate of hexamine was 300 g t(-1) (NaHe300) or 600 g t(-1) (NaHe600). Additional treatments were the untreated control (Con), and formic acid (FA) applied at a rate of 4 L t(-1) (1000 g kg(-1)). RESULTS Additives improved silage quality noticeably only by reducing silage ammonia content compared with the control. The addition of hexamine to a sodium nitrite solution did not improve silage quality compared with the solution containing sodium nitrite alone. The increasing addition of hexamine resulted in linearly rising pH values (P <0.001) and decreasing amounts of lactic acid (P <0.01). Sodium nitrite based additives were more effective than formic acid in preventing butyric acid formation. Additives did not restrict the growth of Saccharomyces cerevisiae compared to the control. CONCLUSION The addition of hexamine did not improve silage quality compared with a solution of sodium nitrite. (c) 2018 Society of Chemical IndustryPeer reviewe

Soil-tree-atmosphere CH4 flux dynamics of boreal birch and spruce trees during spring leaf-out

Peer reviewe

Study of the effect of the bacterial and fungal communities present in real wastewatereffluents on the performance of fungal treatments

The use of the ligninolytic fungi Trametes versicolor for the degradation of micropollutants has been widely studied. However, few studies have addressed the treatment of real wastewater containing pharmaceutically active compounds (PhAC) under non-sterile conditions. The main drawback of performing such treatments is the difficulty for the inoculated fungus to successfully compete with the other microorganisms growing in the bioreactor. In the present study, several fungal treatments were performed under non-sterile conditions in continuous operational mode with two types of real wastewater effluent, namely, a reverse osmosis concentrate (ROC) from a wastewater treatment plant and a veterinary hospital wastewater (VHW). In all cases, the setup consisted of two parallel reactors: one inoculated with T. versicolor and one non-inoculated, which was used as the control. The main objective of this work was to correlate the operational conditions and traditional monitoring parameters, such as laccase activity, with PhAC removal and the composition of the microbial communities developed inside the bioreactors. For that purpose a variety of biochemical and molecular biology analyses were performed: phospholipid fatty acids analysis (PLFA), quantitative PCR (qPCR) and denaturing gradient gel electrophoresis (DGGE) followed by sequencing. The results show that many indigenous fungi (and not only bacteria, which were the focus of the majority of previously published research) can successfully compete with the inoculated fungi (i.e., Trichoderma asperellum overtook T. versicolor in the ROC treatment). We also showed that the wastewater origin and the operational conditions had a stronger impact on the diversity of microbial communities developed in the bioreactors than the inoculation or not with T. versicolor

Valkolupiinin soveltuvuus säilörehuksi

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Effect of no-till followed by crop diversification on the soil microbiome in a boreal short cereal rotation

Diversification of agricultural practices, including changes in crop rotation, intercropping or cover cropping, influence the soil microbiome. Here the impact of tillage and crop diversification on the soil microbiome is reported, being one of the few boreal studies. The field experiment consisted of four treatments with four replications all having a short cereal rotation practice namely an oat (Avena sativa) – spring barley (Hordeum vulgare) – wheat (Triticum aestivum) rotation for the past 10 years until spring 2018. During that period two of the treatments were conventionally tilled with moldboard ploughing whereas the other two were no-tillage treatments. From the growing season 2018 until fall 2020 the main crop in all treatments was spring barley. The first conventional tillage treatment was diversified with English ryegrass (Lolium perenne) as an undersown cover crop for the next three growing seasons. The first no-tillage treatment continued with spring barley only. The second conventional tillage and no-tillage treatment had winter rapeseed in rotation in 2019. Bulk soils were sampled in May 2018 before diversification and then in October 2018, 2019, and 2020. The results showed a clear effect of tillage on the beta-diversity of the soil microbiome and an increase in fungal richness. Barley monoculture interrupted with winter rapeseed resulted in a minor change of the fungal and bacterial community composition. Other fungal and bacterial alpha diversity measures did not react to tillage or diversification nor did the gene copy abundances involved in the N cycle. In conclusion tillage had a profound effect on the soil microbiome hindering impact of the diversificationThe work was funded within the project “Crop diversification and low-input farming across Europe: from practitioners’ engagement and ecosystems services to increased revenues and value chain organization” (Diverfarming) under the European Union’s Horizon 2020 Programme for Research & Innovation, grant agreement no. 728003Peer reviewe

SIP-leimaus ja syväsekvensointi paljastavat suon metaania hapettavan mikrobiyhteisön toiminnallisen monimuotoisuuden

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