Soil microclimate changes affect soil fungal communities in a Mediterranean pine forest

Soil microclimate is a potentially important regulator of the composition of plant‐associated fungal communities in climates with significant drought periods. Here, we investigated the spatio‐temporal dynamics of soil fungal communities in a Mediterranean Pinus pinaster forest in relation to soil moisture and temperature. Fungal communities in 336 soil samples collected monthly over 1 year from 28 long‐term experimental plots were assessed by PacBio sequencing of ITS2 amplicons. Total fungal biomass was estimated by analysing ergosterol. Community changes were analysed in the context of functional traits. Soil fungal biomass was lowest during summer and late winter and highest during autumn, concurrent with a greater relative abundance of mycorrhizal species. Intra‐annual spatio‐temporal changes in community composition correlated significantly with soil moisture and temperature. Mycorrhizal fungi were less affected by summer drought than free‐living fungi. In particular, mycorrhizal species of the short‐distance exploration type increased in relative abundance under dry conditions, whereas species of the long‐distance exploration type were more abundant under wetter conditions. Our observations demonstrate a potential for compositional and functional shifts in fungal communities in response to changing climatic conditions. Free‐living fungi and mycorrhizal species with extensive mycelia may be negatively affected by increasing drought periods in Mediterranean forest ecosystems.info:eu-repo/semantics/acceptedVersio

A new species of Stenobiella Tillyard (Neuroptera, Berothidae) from Australia

Stenobiella variola sp. n., a new species of beaded lacewing (Neuroptera: Berothidae), is described and figured from south-eastern Australia. A preliminary key to Stenobiella species is presented

Extreme rainfall affects assembly of the root-associated fungal community

Global warming is resulting in increased frequency of weather extremes. Root-associated fungi play important roles in terrestrial biogeochemical cycling processes, but the way in which they are affected by extreme weather is unclear. Here, we performed long-term field monitoring of the root-associated fungus community of a short rotation coppice willow plantation, and compared community dynamics before and after a once in 100 yr rainfall event that occurred in the UK in 2012. Monitoring of the root-associated fungi was performed over a 3-yr period by metabarcoding the fungal internal transcribed spacer (ITS) region. Repeated soil testing and continuous climatic monitoring supplemented community data, and the relative effects of environmental and temporal variation were determined on the root-associated fungal community. Soil saturation and surface water were recorded throughout the early growing season of 2012, following extreme rainfall. This was associated with a crash in the richness and relative abundance of ectomycorrhizal fungi, with each declining by over 50%. Richness and relative abundance of saprophytes and pathogens increased. We conclude that extreme rainfall events may be important yet overlooked determinants of root-associated fungal community assembly. Given the integral role of ectomycorrhizal fungi in biogeochemical cycles, these events may have considerable impacts upon the functioning of terrestrial ecosystems

The Mycelium as a network

The characteristic growth pattern of fungal mycelia as an interconnected network has a major impact on how cellular events operating on a micron scale affect colony behavior at an ecological scale. Network structure is intimately linked to flows of resources across the network that in turn modify the network architecture itself. This complex interplay shapes the incredibly plastic behavior of fungi and allows them to cope with patchy, ephemeral resources, competition, damage, and predation in a manner completely different from multicellular plants or animals. Here, we try to link network structure with impact on resource movement at different scales of organization to understand the benefits and challenges of organisms that grow as connected networks. This inevitably involves an interdisciplinary approach whereby mathematical modeling helps to provide a bridge between information gleaned by traditional cell and molecular techniques or biophysical approaches at a hyphal level, with observations of colony dynamics and behavior at an ecological level

Comparative genomic analysis of innate immunity reveals novel and conserved components in crustacean food crop species

Abstract Background Growing global demands for crustacean food crop species have driven large investments in aquaculture research worldwide. However, large-scale production is susceptible to pathogen-mediated destruction particularly in developing economies. Thus, a thorough understanding of the immune system components of food crop species is imperative for research to combat pathogens. Results Through a comparative genomics approach utilising extant data from 55 species, we describe the innate immune system of the class Malacostraca, which includes all food crop species. We identify 7407 malacostracan genes from 39 gene families implicated in different aspects of host defence and demonstrate dynamic evolution of innate immunity components within this group. Malacostracans have achieved flexibility in recognising infectious agents through divergent evolution and expansion of pathogen recognition receptors genes. Antiviral RNAi, Toll and JAK-STAT signal transduction pathways have remained conserved within Malacostraca, although the Imd pathway appears to lack several key components. Immune effectors such as the antimicrobial peptides (AMPs) have unique evolutionary profiles, with many malacostracan AMPs not found in other arthropods. Lastly, we describe four putative novel immune gene families, potentially representing important evolutionary novelties of the malacostracan immune system. Conclusion Our analyses across the broader Malacostraca have allowed us to not only draw analogies with other arthropods but also to identify evolutionary novelties in immune modulation components and form strong hypotheses as to when key pathways have evolved or diverged. This will serve as a key resource for future immunology research in crustacean food crops