Epidemiology, Biotic Interactions and Biological Control of Armillarioids in the Northern Hemisphere

Abstract

Armillarioids, including the genera Armillaria, Desarmillaria and Guyanagaster, represent white-rot specific fungal saprotrophs with soilborne pathogenic potentials on woody hosts. They propagate in the soil by root-like rhizomorphs, connecting between susceptible root sections of their hosts, and often forming extended colonies in native forests. Pathogenic abilities of Armillaria and Desarmillaria genets can readily manifest in compromised hosts, or hosts with full vigour can be invaded by virulent mycelia when exposed to a larger number of newly formed genets. Armillaria root rot-related symptoms are indicators of ecological imbalances in native forests and plantations at the rhizosphere levels, often related to abiotic environmental threats, and most likely unfavourable changes in the microbiome compositions in the interactive zone of the roots. The less-studied biotic impacts that contribute to armillarioid host infection include fungi and insects, as well as forest conditions. On the other hand, negative biotic impactors, like bacterial communities, antagonistic fungi, nematodes and plant-derived substances may find applications in the environment-friendly, biological control of armillarioid root diseases, which can be used instead of, or in combination with the classical, but frequently problematic silvicultural and chemical control measures.

Az erdészeti tudományok története Magyarországon

“…A Soproni Egyetem Funkcionális Genomika és Bioinformatika Kutatócsoportja a legutóbbi időkben jelentős nemzetközi visszhangot kiváltó genetikai kutatásokat folytatott/ folytat a több fafajon (így a tölgyeken is) jelentős kórokozóként ismert Armillaria nem-Armillaria nem-Armillaria zetség fajain. Meghatározták tíznél több Armillaria faj teljes genomszekvenciáját, illetve Armillaria faj teljes genomszekvenciáját, illetve Armillaria eredményeket értek el a fajok elleni biológiai védekezés lehetőségeit illetően is (Sipos et al 2017(Sipos et al , 2021Chen et al 2019;Kedves et al 2021).…”

Decoding the RNA virome of the tree parasite Armillaria provides new insights into the viral community of soil‐borne fungi

“…Controlling Armillaria root disease is challenging because the fungus lives hidden in the soil and root system of infected trees and can also endure a long time in woody debris (Coetzee et al, 2001;Kedves et al, 2021;Redfern & Filip, 1991;Travadon et al, 2012). Therefore, Linnakoski et al (2021) recently argued that the large clonal individuals living in the soil may be optimal targets for the application of viral biocontrol agents and, thus, confirmed by RNA-Sequencing of Armillaria species the presence of four single-stranded (ss) RNA viruses in the secondary pathogens Armillaria borealis and A. cepistipes from Finland, while the other nine detected ssRNA viruses were from other regions of the world (Siberia, South Africa, The United States, Asia, Australia and Oceania).…”

Genomic Comparisons of Two Armillaria Species with Different Ecological Behaviors and Their Associated Soil Microbial Communities

“…Soil metagenomics or metabarcoding can be used to identify important fungi, bacteria, and archaea associated with tree health [43]. Determinations of the soil micro ora can allow evaluations of treatment (e.g., soil amendments, forest thinning, underburning) in uences on naturally occurring microbial communities that favor or suppress forest root diseases/pathogens, which could provide new approaches to manage Armillaria root disease [20,44,45].…”