scholarly journals Aspen leaves as a “chemical landscape” for fungal endophyte diversity – Can nitrogen and herbivory shape the community composition in controlled conditions?

2020 ◽  
Author(s):  
Johanna Witzell ◽  
Vicki Huizu Guo Decker ◽  
Marta Agostinelli ◽  
Carmen Romeralo Tapia ◽  
Michelle Cleary ◽  
...  
Keyword(s):  
Community Composition ◽  
Fungal Endophyte ◽  
Fungal Community Composition ◽  
Leaf Beetles ◽  
Treatment Variation ◽  
Greenhouse Study ◽  
Ecological Performance ◽  
Abiotic And Biotic Factors ◽  
Chemical Traits

AbstractThe endophytic microbiome may influence the ecological performance of plants, including forest trees. Various abiotic and biotic factors may shape the endophyte communities directly but also indirectly, by modifying the quality of host plants as a substrate. We hypothesized that potentially antifungal or fungistatic condensed tannins (CTs) would determine the quality of aspen (Populus tremula) leaves as a substrate for endophytic fungi. By subjecting the plants to nitrogen fertilization (N) or herbivory (H; leaf beetles) we aimed to change the internal “chemical landscape”, especially the CT levels, in aspen leaves. We expected that this would lead to changes in the fungal community composition, in line with the predictions of heterogeneity-diversity relationship hypothesis. To test this we conducted a greenhouse study where aspen plants were subjected to N and H treatments, individually or in combination. The chemical status of the leaves was analysed using GC/MS (114 metabolites), LC/MS (11 phenolics) and UV-spectrometry (CTs) and the endophytic communities were characterized using culture-dependent sequencing. Nitrogen treatment, alone or in combination with herbivory had a suppressing effect on the concentration and within-treatment variation in the CT precursors, catechins, and resulted in similar trend also in CTs. Nitrogen increased the concentration of certain amino acids, and it also tended to increase most of the analysed sugars sugars. Herbivory had a negligible effect on chemical traits. In N-treated plants, the endophyte richness and abundance were higher than in plants exposed to H, but in general, the diversity of the culturable endophytes remaind stable despite the subtle changes in leaf chemistry.

scholarly journals Space and Vine Cultivar Interact to Determine the Arbuscular Mycorrhizal Fungal Community Composition

2020 ◽  
Vol 6 (4) ◽  
pp. 317
Author(s):  
Álvaro López-García ◽  
José A. Jurado-Rivera ◽  
Josefina Bota ◽  
Josep Cifre ◽  
Elena Baraza
Keyword(s):  
Community Composition ◽  
Fungal Community ◽  
Cropping Systems ◽  
Arbuscular Mycorrhizal ◽  
Major Effect ◽  
Sample Type ◽  
Fungal Community Composition ◽  
Fungal Associations ◽  
Abiotic And Biotic Factors ◽  
Mallorca Island

The interest in the use of microbes as biofertilizers is increasing in recent years as the demands for sustainable cropping systems become more pressing. Although very widely used as biofertilizers, arbuscular mycorrhizal (AM) fungal associations with specific crops have received little attention and knowledge is limited, especially in the case of vineyards. In this study, the AM fungal community associated with soil and roots of a vineyard on Mallorca Island, Spain was characterized by DNA sequencing to resolve the relative importance of grape variety on their diversity and composition. Overall, soil contained a wider AM fungal diversity than plant roots, and this was found at both taxonomic and phylogenetic levels. The major effect on community composition was associated with sample type, either root or soil material, with a significant effect for the variety of the grape. This effect interacted with the spatial distribution of the plants. Such an interaction revealed a hierarchical effect of abiotic and biotic factors in shaping the composition of AM fungal communities. Our results have direct implications for the understanding of plant-fungal assemblages and the potential functional differences across plants in vineyard cropping.

scholarly journals Earthworms drastically change fungal and bacterial communities during vermicomposting of sewage sludge

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jorge Domínguez ◽  
Manuel Aira ◽  
Keith A. Crandall ◽  
Marcos Pérez-Losada
Keyword(s):  
Sewage Sludge ◽  
Community Composition ◽  
Fungal Community ◽  
High Throughput Sequencing ◽  
Wastewater Treatment Plants ◽  
Agricultural Practices ◽  
Fungal Community Composition ◽  
Earthworm Casts ◽  
Composition And Structure ◽  
Sustainable Agricultural Practices

AbstractWastewater treatment plants produce hundreds of million tons of sewage sludge every year all over the world. Vermicomposting is well established worldwide and has been successful at processing sewage sludge, which can contribute to alleviate the severe environmental problems caused by its disposal. Here, we utilized 16S and ITS rRNA high-throughput sequencing to characterize bacterial and fungal community composition and structure during the gut- and cast-associated processes (GAP and CAP, respectively) of vermicomposting of sewage sludge. Bacterial and fungal communities of earthworm casts were mainly composed of microbial taxa not found in the sewage sludge; thus most of the bacterial (96%) and fungal (91%) taxa in the sewage sludge were eliminated during vermicomposting, mainly through the GAP. Upon completion of GAP and during CAP, modified microbial communities undergo a succession process leading to more diverse microbiotas than those found in sewage sludge. Consequently, bacterial and fungal community composition changed significantly during vermicomposting. Vermicomposting of sewage resulted in a stable and rich microbial community with potential biostimulant properties that may aid plant growth. Our results support the use of vermicompost derived from sewage sludge for sustainable agricultural practices, if heavy metals or other pollutants are under legislation limits or adequately treated.

scholarly journals Assessing Genotypic and Environmental Effects on Endophyte Communities of Fraxinus (Ash) Using Culture Dependent and Independent DNA Sequencing

2021 ◽  
Vol 7 (7) ◽  
pp. 565
Author(s):  
Anindita Lahiri ◽  
Brian R. Murphy ◽  
Trevor R. Hodkinson
Keyword(s):  
Community Composition ◽  
Environmental Effects ◽  
High Throughput Sequencing ◽  
Fungal Community Composition ◽  
Species Identity ◽  
Ash Dieback ◽  
Hymenoscyphus Fraxineus ◽  
Culture Independent ◽  
The Impact ◽  
Culture Dependent

Fraxinus excelsior populations are in decline due to the ash dieback disease Hymenoscyphus fraxineus. It is important to understand genotypic and environmental effects on its fungal microbiome to develop disease management strategies. To do this, we used culture dependent and culture independent approaches to characterize endophyte material from contrasting ash provenances, environments, and tissues (leaves, roots, seeds). Endophytes were isolated and identified using nrITS, LSU, or tef DNA loci in the culture dependent assessments, which were mostly Ascomycota and assigned to 37 families. Few taxa were shared between roots and leaves. The culture independent approach used high throughput sequencing (HTS) of nrITS amplicons directly from plant DNA and detected 35 families. Large differences were found in OTU diversity and community composition estimated by the contrasting approaches and these data need to be combined for estimations of the core endophyte communities. Species richness and Shannon index values were highest for the leaf material and the French population. Few species were shared between seed and leaf tissue. PCoA and NMDS of the HTS data showed that seed and leaf microbiome communities were highly distinct and that there was a strong influence of Fraxinus species identity on their fungal community composition. The results will facilitate a better understanding of ash fungal ecology and are a step toward identifying microbial biocontrol systems to minimize the impact of the disease.

Do fungi and bacteria respond similar across a steep local pH gradient?

2021 ◽  
Author(s):  
Rasmus Kjoller ◽  
Carla Cruz-Paredes
Keyword(s):  
Community Composition ◽  
Soil Ph ◽  
Wood Ash ◽  
Ph Gradient ◽  
Fungal Communities ◽  
Ph Effects ◽  
Fungal Community Composition ◽  
Ph Gradients ◽  
Field Samples ◽  
Bacterial Richness

<p>Soil pH is consistently recorded as the single most important variable explaining bacterial richness and community composition locally as globally. Bacterial richness responds to soil pH in a bell-shaped pattern, highest in soils with near-neutral pH, while lower diversity is found in soil with pH >8 and <4.5. Also, community turnover is strongly determined by pH for bacteria. In contrast, pH effects on fungi is apparently less pronounced though also much less studied compared to bacteria. Still, pH appears to be a significant determinant for fungal communities but typically not the most important. Rarely are bacterial and fungal communities co-analyzed from the same field samples taken across pH gradients. Here we analyze the community responses of fungi and bacteria in parallel over an extreme pH gradient ranging from pH 4 to 8 established by applying strongly alkaline wood ash to replicated plots in a Picea abies plantation. Bacterial and fungal community composition were assessed by amplicon-based meta-barcoding. Bacterial richness were not significantly affected by pH, while fungal richness and a-diversity were stimulated with higher pH. We found that both, bacterial and fungal communities increasingly deviated from the untreated plots with increasing amount of wood ash though fungal communities were more resistant to changes than bacterial. Soil NH<sub>4</sub>, NO<sub>3</sub> and pH significantly correlated with the NMDS pattern for both bacterial and fungal communities. In the presentation we will discuss resistance versus sensitivity of different fungal functional guilds towards higher pH as well as the underlying factors explaining the community changes.</p>

Sign in / Sign up

Export Citation Format

Share Document