| Title: | Aspen Leaves as a 'Chemical Landscape' for Fungal Endophyte Diversity-Effects of Nitrogen Addition |
| Author(s): | Witzell J; Decker VHG; Agostinelli M; Romeralo C; Cleary M; Albrectsen BR; |
| Address: | "Forestry and Wood Technology, Linnaeus University, Vaxjo, Sweden. Southern Swedish Forest Research Centre, Swedish University of Agricultural Sciences, Alnarp, Sweden. Department of Plant Physiology, Umea Plant Science Center, Umea University, Umea, Sweden. Forest Research Centre (INIA, CSIC), Madrid, Spain" |
| DOI: | 10.3389/fmicb.2022.846208 |
| ISSN/ISBN: | 1664-302X (Print) 1664-302X (Electronic) 1664-302X (Linking) |
| Abstract: | "Abiotic and biotic factors may shape the mycobiome communities in plants directly but also indirectly by modifying the quality of host plants as a substrate. We hypothesized that nitrogen fertilization (N) would determine the quality of aspen (Populus tremula) leaves as a substrate for the endophytic fungi, and that by subjecting the plants to N, we could manipulate the concentrations of positive (nutritious) and negative (antifungal) chemicals in leaves, thus changing the internal 'chemical landscape' for the fungi. We expected that this would lead to changes in the fungal community composition, in line with the predictions of heterogeneity-diversity relationship and resource availability hypotheses. To test this, we conducted a greenhouse study where aspen plants were subjected to N treatment. The chemical status of the leaves was confirmed using GC/MS (114 metabolites, including amino acids and sugars), LC/MS (11 phenolics), and UV-spectrometry (antifungal condensed tannins, CTs), and the endophytic communities were characterized using culture-dependent sequencing. We found that N treatment reduced foliar concentrations of CT precursor catechin but not that of CTs. Nitrogen treatment also increased the concentrations of the amino acids and reduced the concentration of some sugars. We introduced beetle herbivores (H) as a second treatment but found no rapid changes in chemical traits nor strong effect on the diversity of endophytes induced by herbivores. A few rare fungi were associated with and potentially vectored by the beetle herbivores. Our findings indicate that in a controlled environment, the externally induced changes did not strongly alter endophyte diversity in aspen leaves" |
| Keywords: | Chrysomela tremula Populus tremula condensed tannins fungal endophytes heterogeneity-diversity relationship hypothesis phenolics; |
| Notes: | "PubMed-not-MEDLINEWitzell, Johanna Decker, Vicki Huizu Guo Agostinelli, Marta Romeralo, Carmen Cleary, Michelle Albrectsen, Benedicte Riber eng Switzerland 2022/04/08 Front Microbiol. 2022 Mar 21; 13:846208. doi: 10.3389/fmicb.2022.846208. eCollection 2022" |
