ESPM 134 Spring 2009 Introduction to the fungi
The Hypha
Jacobson, Hickey, Glass & Read
Arbuscule (basically a haustorium) inside a plant root cell
(c) D. Redecker, K. Wex
Mycelium all of the hyphae of a single individual fungus It can function to move materials from one area to another
A. H. R. Buller 1931
Hyphal Fusion a necessary step in maintaining a mycelium
Hickey, Jacobson, Glass & Read
Extensive mycelium of an ectomycorrhizal fungus The individual strands you see are rhizomorphs: bundles of organized hyphae used for long-distance transport
Rhizomorphs of Mutinus elegans in a Miscanthus field
Ratios of two haploid nuclei in Heterbasidion parviporum heterokaryons From James et al 2008 Evolution paper
Mitotic (asexual) spore state are very common in Ascomycete
Zone lines in wood cause by vegetative interactions between different genotypes of decay fungi
Zone lines in a twig showing borders of individual fungi
Single individuals can be large Suillus pungens genets in pre-fire Pt. Reyes Bonello et al. 1998. New Phytol. 138:533-542.
Undisturbed forest should have large genets Boletus photoshopii
Achyla oogonium and antheridia
Oomycota the water molds (fungal-like protists)
Saprolegnia life cycle from Alexopolous et al
Damping off by Pythium
Chemotactic zoospores of Phytophthora
Phytophthora infestans, late blight of potato airborne sporangia can disperse across a continent in year
Sudden Oak death - Phytophthora ramorum At China camp State park, Marin Co.
“true fungi” are in the Kingdom Fungi
Kingdom Fungi
Chytridiomycota + Zygomycota Glomales Ascomycota
Basidiomycota
Arbuscular mycorrhiza (Plantago media and Glomus clarum) extraradical hyphae
spore 100µm (c) D. Redecker
Photo from Ann Pringle
Hallmark of the Ascomycota - the Ascus
Mitotic (asexual) spore state are very common in Ascomycete
Apothecia cup-like ascocarps With asci on the surface
Perithecium - a common ascocarp type Small with asci inside a flask-shaped structure
Xylaria - a wood decaying ascomycete that forms a stroma with perithecia embedded in it
Basidiomycetes - a major group of Forest Pathogens and mycorrhizal symbionts Basidia from Alexopoulos et al.
Hyphae with clamps
From Ingold 1953
Coprinus development
From Buller
Mushrooms (Agarics & Boletes)
Tooth fungi (Hydnoid)
Polypores
Club and Coral fungi Resupinate Corticioid
Jelly fungi
Gastromycetes Puffballs &falsetruffles
Rust fungi
Importance and size of meiotic (sexual) stage Basidiomycota (except rusts) Fruiting bodies often large and conspicuous, basidiospores often the main dispersal stage;
Rust fungi (also Basidiomycota) Fruiting body usually small, basidiospores often used to infect a different host, dispersal relatively local
Ascomycota
Oomycota
Fruiting body usually small, in many species it may be rare or absent.
No fruiting bodies. Oospores Small and inconspicuous; a resting stage that disperses primarily through time not space.
Importance and size of mitotic (asexual) stage
Basidiomycota (except rusts) rare, usually used for genetic exchange, not dispersal
Rust fungi (also Basidiomycota) Usually abundant, often used for longrange dispersal
Ascomycota
Oomycota
Usually abundant, and often the primary inoculum for dispersal and colonization.
abundant. The most important stage for infection. (zoospores, chlamydospores, whole sporangia)
Size of mycelium and presence of rhizomorphs or cords Basidiomycota (except rusts) small to very large (> sq mile) Rhizomorphs and cords common
Rust fungi (also Basidiomycota) small always localized in a single host - But single genotypes can be dispersed long distances by mitotic spores; Rhizomorphs and cords absent
Ascomycota
Oomycota
small to moderate localized in a single host or unit resource (like a log). Rhizomorphs and cords present in some species
basically small, but can cause large root disease centers probably by locally dispersed spores rather than mycelial growth, Rhizomorphs and cords absent
Importance in wood decay and ectomycomycorrhizal (EM) symbiosis Basidiomycota (except rusts) Causal agent for most decay
Rust fungi (also Basidiomycota) None
Ascomycota
Oomycota
few important decays Hypoxylon and Xylaria are the main exceptions
Most EM fungi are basidiomycetes
None
Some important EM fungi (e.g. truffles)
Phytophthora cinnamomi apparently decays small to moderate roots, but otherwise this behavior is rare. None
Importance in various types of diseases Basidiomycota (except rusts) Most root diseases, virtually all that involve decay are basidiomycetes
Rust fungi (also Basidiomycota) None
Ascomycota
Oomycota
A few important root diseases (e.g. Blackstain), these usually behave as wilts and do not cause decay.
Foliage diseases
almost none
very common
Commmon - all needle cast and needle blights
Canker diseases
some canker rots
many important cankers of pines
Most cankers diseases
insect vectoring
rare, but occurs with someare vectored by bark beetles (e.g. Peniophora, and Western and Southern pine beetles) or wood wasps (e.g. Amylostereum)
Used for genetic exchange by most rusts (i.e., the spermatial stage)
Most of the fungi vectored by bark beetles and ambrosial beetles are members of the Ascomycota (e.g. blues stains, black stain), ambrosia fungi)
Phytophthora cinnamomi and others cause serious root diseases; Phythium species cause damping off and many cryptic sublethal root disease. Many in tropical setting, Phytophthora ramorum is a temperate example Phytophthora ramorum and others can cause cankers none
Root diseases
Nematode trapping fungi Trap types
adhesive net traps
Constricting ring traps
Non-constricting ring traps
Rotifer trapping From Barron and Szijarto 1991
Stylopage anomala trapping amoebae
Photos from George Barron.
Bacteriophagy from Barron 1988 Can. J. Bot.
