CellBioNewsAug 10, 2023

A single #gene and a unique layer of #regulation opens the door for novel #plant-#fungi interactions

#ectomycorrhizae #PtLecRLK1 #Laccaria

https://phys.org/news/2023-08-gene-unique-layer-door-plant-fungi.html

A single gene and a unique layer of regulation opens the door for novel plant-fungi interactions

Soil fungi known as ectomycorrhizae (ECM) can penetrate plant roots and provide water and nutrients to host plants in exchange for sugar. This symbiotic relationship benefits the plant, increasing its growth. To benefit from these fungi while protecting themselves from harmful ones such as pathogens, plants have evolved a complex layer of regulation that determines which fungi can inhabit their root system.

Phys.org
CellBioNewsMay 11, 2023

Re‐examining the underground connections between #trees.

#fungi #ectomycorrhizae #soil #microbiome

https://phys.org/news/2023-05-reexamining-underground-trees.html

Re‐examining the underground connections between trees

Fungal networks interconnecting trees in a forest is a key factor that determines the nature of forests and their response to climate change. These networks have also been viewed as a means for trees to help their offspring and other tree-friends, according to the increasingly popular "mother tree hypothesis." An international group of researchers re-examined the evidence for and against this hypothesis in a new study.

PestinfoMay 10, 2023
In parts of North America, #beech trees are infected with the emerging beech leaf disease, caused by the foliar #nematode Litylenchus crenatae. However, the roots of the diseased trees and their #ectomycorrhizae are also affected. Studies in Journal of Fungi (2023, vol. 9 (4), art. 497 by Claudia Bashian-Victoroff and others - https://doi.org/10.3390/jof9040497
Beech Leaf Disease Severity Affects Ectomycorrhizal Colonization and Fungal Taxa Composition

Beech leaf disease (BLD) is an emerging forest infestation affecting beech trees (Fagus spp.) in the midwestern and northeastern United States and southeastern Canada. BLD is attributed to the newly recognized nematode Litylenchus crenatae subsp. mccannii. First described in Lake County, Ohio, BLD leads to the disfigurement of leaves, canopy loss, and eventual tree mortality. Canopy loss limits photosynthetic capacity, likely impacting tree allocation to belowground carbon storage. Ectomycorrhizal fungi are root symbionts, which rely on the photosynthesis of autotrophs for nutrition and growth. Because BLD limits tree photosynthetic capacity, ECM fungi may receive less carbohydrates when associating with severely affected trees compared with trees without BLD symptoms. We sampled root fragments from cultivated F. grandifolia sourced from two provenances (Michigan and Maine) at two timepoints (fall 2020 and spring 2021) to test whether BLD symptom severity alters colonization by ectomycorrhizal fungi and fungal community composition. The studied trees are part of a long-term beech bark disease resistance plantation at the Holden Arboretum. We sampled from replicates across three levels of BLD symptom severity and compared fungal colonization via visual scoring of ectomycorrhizal root tip abundance. Effects of BLD on fungal communities were determined through high-throughput sequencing. We found that ectomycorrhizal root tip abundance was significantly reduced on the roots of individuals of the poor canopy condition resulting from BLD, but only in the fall 2020 collection. We found significantly more ectomycorrhizal root tips from root fragments collected in fall 2020 than in spring 2021, suggesting a seasonal effect. Community composition of ectomycorrhizal fungi was not impacted by tree condition but did vary between provenances. We found significant species level responses of ectomycorrhizal fungi between levels of both provenance and tree condition. Of the taxa analyzed, two zOTUs had significantly lower abundance in high-symptomatology trees compared with low-symptomatology trees. These results provide the first indication of a belowground effect of BLD on ectomycorrhizal fungi and contribute further evidence to the role of these root symbionts in studies of tree disease and forest pathology.

MDPI