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Veterinary and growth‐promoting antibiotics are widely used in animal husbandry and accumulate in manure‐fertilized soils. However, the impact of these antibiotics on symbiotic nitrogen fixation is poorly understood. We investigated the effect of the veterinary antibiotics oxytetracycline and sulfamethazine, and a combination of both, on nitrogen fixation in alfalfa (Medicago sativa L.) inoculated with Sinorhizobium meliloti. In a pot experiment, M. sativa was grown in soils fertilized with fresh manure that contained environmentally relevant antibiotic concentrations (0.2, 2, and 200 mg kg−1). Nodulation, nitrogen fixation, and nutrient concentrations were determined in the alfalfa plants and soils after 12 wk. Compared with the antibiotic‐free control, symbiotic nitrogen fixation increased significantly in soils mixed with manure containing 2 and 200 mg kg−1 oxytetracycline (20.1 and 20.8% increase, respectively) and a mixture of 200 mg kg−1 oxytetracycline and sulfamethazine (12.4% increase). The measured plant‐ and soil‐related parameters failed to explain the observed increase in nitrogen fixation. However, using concentration levels that accurately reflect common agricultural practices, we obtained results that directly contradict other experiments conducted under unrealistically high antibiotic concentrations. Core Ideas: Oxytetracycline in soil increased symbiotic N fixation of alfalfa.Sulfamethazine did not affect N fixation.Findings contradict previous studies, likely due to lower antibiotic concentrations.Differences in nitrogen fixation were independent from soil mineral N. [ABSTRACT FROM AUTHOR]

Fungi are considered among the most efficient microbial degraders of plastics, as they produce salient enzymes and can survive on recalcitrant compounds with limited nutrients. In recent years, studies have reported numerous species of fungi that can degrade different types of plastics, yet there remain many gaps in our understanding of the processes involved in biodegradation. In addition, many unknowns need to be resolved regarding the fungal enzymes responsible for plastic fragmentation and the regulatory mechanisms which fungi use to hydrolyse, assimilate and mineralize synthetic plastics. This review aims to detail the main methods used in plastic hydrolysis by fungi, key enzymatic and molecular mechanisms, chemical agents that enhance the enzymatic breakdown of plastics, and viable industrial applications. Considering that polymers such as lignin, bioplastics, phenolics, and other petroleum-based compounds exhibit closely related characteristics in terms of hydrophobicity and structure, and are degraded by similar fungal enzymes as plastics, we have reasoned that genes that have been reported to regulate the biodegradation of these compounds or their homologs could equally be involved in the regulation of plastic degrading enzymes in fungi. Thus, this review highlights and provides insight into some of the most likely regulatory mechanisms by which fungi degrade plastics, target enzymes, genes, and transcription factors involved in the process, as well as key limitations to industrial upscaling of plastic biodegradation and biological approaches that can be employed to overcome these challenges. [Display omitted] • Hydrolase and oxidoreductase enzymes are responsible for the fungal degradation of plastics. • Fungal HsbA proteins facilitate the attachment of hydrolases onto hydrophobic plastic surfaces. • Extracellular stimuli regulate the induction of plastic-degrading genes via transcription factors. • Chemical pre-treatment, composting, microbial consortia and gene engineering accelerates the biodegradation process. [ABSTRACT FROM AUTHOR]

Vast areas of degraded land have proliferated worldwide. In response to this transformation, ambitious targets have been set to restore degraded ecosystems, such as the the Bonn Challenge, which aims to restore 350 million ha of forestland by 2030. Achieving such goals will require a larger evidence base of restoration studies, which could be realized by systematically embedding scientific experiments within restoration programs. We examine the feasibility of this strategy with examples of successful transdisciplinary research involving embedded experiments in associated fields, and recommend that such field sites be linked to create a global network of embedded experiments. To unify a networked approach, we call on restoration stakeholders to develop acceptable industry standards of experimental design. Finally, we suggest how to use this strategy effectively to meet the biome‐scale challenges of the coming decades. [ABSTRACT FROM AUTHOR]

Monoculture rubber cultivation and its intensive associated human activities are known to have a negative impact on the biodiversity, ecology, and biological conservation of the ecosystems in which they occur. These negative impacts include changes to the biodiversity and function of soil fungal communities, which contribute towards nutrient cycling and interact with other organisms in belowground ecosystems, and may be pathogens. Despite the important role of soil fungi in rubber plantations, these communities have been poorly studied. In this paper, we review the existing literature on the diversity and ecology of belowground fungi in rubber plantations. Various groups of soil fungi, including saprobes, symbionts, and pathogens are discussed. Additionally, the role of plantation management is discussed in the context of both pathogenic soil fungi and the promotion of beneficial soil fungi. Management practices include clone selection, tree age and planting density, application of chemicals, and intercropping systems. Our review shows the strong need for further research into the effects of monoculture rubber plantations on soil fungal communities, and how we can best manage these systems in the future, in order to create a more sustainable approach to rubber production. [ABSTRACT FROM AUTHOR]

We are studying dothideomycetes with muriform ascospores and in this paper provide an account of those species in Amniculicolaceae. In this family muriform ascospores are only known in the genus Murispora. In this paper we introduce the new species M. fagicola (on dead branches of Fagus sylvatica), M. galii (on dead twigs of Galium sp.), M. cardui (on dead twigs of Carduus sp.), M. medicaginicola (on dead twigs of Medicago sp), M. cicognanii (on dead branches of Clematis sp.) and M. hawksworthii (on dead twigs of an unknown woody plant), collected from Italy and the UK. Descriptions, illustrations and justifications for the novelty are provided for each taxon. Morphological character differences and analysis of combined LSU, SSU and EF1-α sequence datasets support the validity of the new species and their placement in Murispora in Amniculicolaceae. The asexual morph of M. hawksworthii was established from single ascospore isolates. [ABSTRACT FROM AUTHOR]

Dothideomycetes with muriform ascospores, were previously placed in family Pleosporaceae, but they are not a monophyletic group, and can be placed across a range of orders and families. In this study an interesting saprobic ascomycete was isolated from Clematis vitalba which was collected in Italy. The species has unique characters and we introduced the taxon as a new genus and species within Lentitheciaceae, The conclusions are drawn from morphology and, LSU, SSU, EF1-α and RPB2 combined sequence analyses. Maximum parsimony (MP), maximum likelihood (ML) and Mr Bayes phylogenetic analysis all support this being a distinct genus within the Lentitheciaceae. It is distinguished from other genera of this family in having muriform ascospores whose central cells have longitudinal septa and light end cells, and ascomata with a thick peridium and a short neck. The new genus is compared with similar genera in the Lentitheciaceae and a comprehensive description, and micrographs are provided. The cultures were obtained via single ascospore isolation, and the asexual state was also established. [ABSTRACT FROM AUTHOR]

More than 1,000 species of bambusicolous fungi have been reported worldwide, although most lack modern morphological description and phylogenetic investigation. Two species of bambusicolous fungi were collected in northern Thailand. Based on morphological characters, and on a comparison with type specimens, they were determined to be Pteridiospora javanica and Roussoellopsis macrospora. In a multigene phylogenetic analysis Pteridiospora javanica formed a sister clade with Astrosphaeriella stellata, while Roussoellopsis macrospora clustered with R. tosaensis in Roussoellaceae. Because the current placement of Astrosphaeriella in Dothideomycetes cannot presently be resolved, the family placement of Pteridiospora javanica is also unresolved. Based on morphology and phylogeny we epitypify our strains under the names Pteridiospora javanica and Roussoellopsis macrospora. Asexual states are also described for both species. [ABSTRACT FROM AUTHOR]

Dematiopleospora mariae, isolated from Ononis spinosa collected in Forlí-Cesena Province in Italy, is introduced as a new ascomycete genus and species based on morphology and combined LSU and SSU sequence analyses. Phylogenetic analysis based on maximum parsimony (MP), maximum likelihood (ML) and Mr Bayes all support Dematiopleospora as being a distinct genus within the Phaeosphaeriaceae. Dematiopleospora is distinguished from other genera in this family in having ascospores whose central cells have longitudinal septa with light end cells, ascomata with a thick peridium and necks comprising short, light brown setae. Phylogenetic analysis also separates Dematiopleospora from other genera in the Phaeosphaeriaceae. Dematiopleospora forms a sister group with Entodesmium and Chaetosphaeronema, but these three genera are clearly separated in the molecular analysis with relatively high bootstrap support (89% and 99% respectively). The new genus is compared with similar genera of Phaeosphaeriaceae and a comprehensive description, and micrographs are provided. [ABSTRACT FROM AUTHOR]

Recent studies have indicated that arbuscular mycorrhizal fungi (AMF) are able to influence litter decomposition by interacting with the soil fungal community. However, it remains unclear exactly which constituent groups of the soil fungal community respond to AMF during litter decomposition, and in what ways. To better understand this relationship, we investigated the effect of AMF on soil fungal communities in a greenhouse experiment. Our study found that the composition and richness of the fungal community, at higher taxonomical levels (e.g. phyla, order), remained stable across treatments. However, the relative abundance of some key genera including Mycena, Glomerella, Pholiotina, and Sistotrema were significantly affected by AMF inoculation. Soil fungal community structure was also altered by AMF inoculation during the later stages of litter decomposition. Our study provides new insights into understanding the interaction between AMF and soil fungal communities and reinforces the importance of AMF in soil nutrient cycling. • Arbuscular mycorrhizal fungi (AMF) suppress the growth of soil fungal communities. • AMF affect key fungal groups associated with litter decomposition in the soil. • Soil fungal community structure is significantly altered by AMF inoculation. [ABSTRACT FROM AUTHOR]