How Do Fungi Get Around? Although relatively few in species, fungi are everywhere. Spore Dispersal The mycelia of some fungi are potentially able to produce up to in Fungi “billions and billions” of spores Not all will give survive, but sheer numbers ensure some will Examples from various groups of fungi. Ustilago maydis (Corn Smut) Ganoderma applanatum (Artist Fungus) Ganoderma applanatum, the Artist Fungus, perennial fruiting body, 30 billion spores/day and 5.4 trillion A gall about 1in3 may contain spores over a five month period, approximately 25 billion from within the pores of the fruiting spores! body. Calvatia gigantea (The Giant Puffball) Bread Mold, A Microscopic Fungus The average size fruiting body of this species is approximately 18” Rhizopus stolonifer, each and contains about 7 trillion spores sporangium contain around within. 50,000 spores. 1 Blue Mold, A Microscopic Fungus How Do Fungi Get Around? Sometimes they don’t!. Resting spores: Thick walled cells with food reserve. Zygospore, enclosed in thick- walled zygosporangium. Zygosporangium Penicillium colony 2.5 cm may produce 400,000 spores/day. How Do Fungi Get Around? How Do Fungi Get Around? Sometimes they don’t!. Sometimes they don’t!. Resting spores: Thick walled cells Resting spores: Thick walled cells with food reserve. with food reserve. Teliospore: Thick walled over Resistant sporangium: Thick wintering spore. walled cell eventually giving rise to zoospores. How Do Fungi Get Around? Wind: Air Borne Spores Fungi usually have mechanism by Most fungi disperse spores by wind. which spores are dispersed. Spores are usually “dry” spores and A number of mechanisms have hydrophobic. Why? evolved in fungi to disperse spores: Most studied group of spores: Wind Aerobiology deals with particles Water transported in air. Insects Fungal spores can cause allergies Animals unknown until 1924. Active mechanisms Mostly caused by common microscopic fungi = molds 2 Wind: Air Borne Spores Wind: Air Borne Spores Most studied group of spores: Most studied group of spores. Thousands of tons of spores of Christensen (1975): Demonstrated two most common air borne fungi, effectiveness of air dispersal: Cladosporium and Penicillium, Utilized Cladosporium resinae, have been measured. as a marker fungus. Air samples may contain Species known only from resin approximately 200,000 permeated soil or wood spores/meter3. impregnated with coal tar Particles easily suspended in light creosote, i.e., telephone poles beam. and in diesel fuel. Wind: Air Borne Spores Christensen (1975): Demonstrated effectiveness of air dispersal: 4 Species released in Plant Pathology Building at University 3 of Minnesota. A building with four floors and no central air 2 conditioning. 1 Side View of Building Hallway Top View of Building Cladosporium resinae spores “brushed” into air on 1st floor. 3 Wind: Air Borne Spores Cladosporium Plate Christensen (1975): Demonstrated effectiveness of air dispersal: In order to grow C. resinae, special medium with creosote required. Creosote medium also prevented other fungi from growing. Wind: Air Borne Spores Wind: Air Borne Spores Christensen (1975): Demonstrated effectiveness of air dispersal: In order to ensure that C. resinae was not already in the air. Plates with creosote medium exposed in building, and soil and wood samples before experiment. Why? Thus, C. resinae not present in plant material and in soil. Wind: Air Borne Spores Wind: Air Borne Spores Christensen (1975): Demonstrated effectiveness of air dispersal: Why select Cladosporium resinae to be experimental fungus? Thus, C. resinae not present in air and experiment sight. 4 Wind: Air Borne Spores Wind: Air Borne Spores Christensen (1975): Demonstrated Christensen (1975): Demonstrated effectiveness of air dispersal: effectiveness of air dispersal: Experiment was in two parts: Experiment demonstrates Plates exposed from 1st to 4th ability of air borne spores to floor, at 5 minute intervals, in stay afloat. labs and hallway. Why select Cladosporium Seven sets of plates exposed resinae to be experimental from 1st to 4th floor, at fungus? intervals of 0-5, 5-10, 10-20, 20-30, 30-60, 60-120 and 120- 240 minutes. Wind: Air Borne Spores Wind: Air Borne Spores Christensen (1975): Demonstrated effectiveness of air dispersal: An experiment that you can do: Place mature mushroom, in box, about 10” high, 36”long. Intuitively, what do you think will happen? Wind: Air Borne Spores Wind: Air Borne Spores Mushroom Ability of spores to stay afloat, placed here indoors, is reason why allergies worst indoors, for some. Allergies worst when sweeping and vacuuming. Top view of spores on cardboard box bottom. Some spores stay afloat and land on opposite end of box! 5 Wind: Air Borne Spores Wind: Air Borne Spores Mechanism of basidiospore release: Basidium ejects basidiospores and Lower magnification of falls between gills to be carried basidiospores falling between the away by wind. gills. Wind: Air Borne Spores Wind: Air Borne Spores So if somebody sneezes in another room, they may as well be sneezing right in your face! Ascomycota fruiting body with asci and ascospores. Wind: Air Borne Spores Puffballs With Flexible Peridium Ascospores Ostiole disperse when Flexible Flexible pressure Peridium within ascus “shoots” spores through operculum Lycoperdon perlatum: Has flexible peridium with an apical ostiole where spores are dispersed when peridium is depressed. 6 Puffballs With Flexible Peridium Puffballs With Flexible Peridium Outer Peridium Inner Peridium with ostiole Geastrum tripex (Earthstar): Has flexible inner peridium with an apical ostiole and a thick, tough outer peridium that dehisces Geastrum tripex: dispersing spores to form a star-shape. following depression of peridium. Puffball With Thick Rigid Peridium Puffballs With Rigid Peridium Peridium Basidiospores Pisolithus tinctorius: Dispersal of Scleroderma levae: Peridium must basidiospores after disintegration dehisce for basidiospores dispersal. of peridium. Peridium Dehiscent How Far and How High? Some spores believed to Battarraea steveni: disperse species world wide. Peridium has a Some spores have been found circumscision as high as 36,000-71,000 feet. dehiscence. Entire So what! top portion of the peridium removed when basidiospores dispersed. 7 Water Dispersed Spores Water Dispersed Spores Water dispersed spores are hydrophillic. They readily absorb water. Spores are usually also borne in slime and are carried away in mass, passively. Some spores have long appendages or are coiled. Shapes give high surface tension to stay afloat. Air also may be trapped. Water Dispersed Spores Water Dispersed Spores Zoospores chemotactic: Movement towards chemical stimulus. Stimulus normally towards food source. Zoospores have flagella, can swim, but is this important? Insect (Fly) Dispersal Insect (Fly) Dispersal Aeroe rubra: A species of stinkhorn. Foul odor attracts flies. Spores, in slime eaten and/or adhere to their Phallus rubicundus, another stinkhorn. bodies. 8 Insect (Fly) Dispersal Mimicry (Pseudoflowers) Puccinia monoica, plant pathogen Dictyophora cinnabarina, yet another induces pseudoflower formation. stinkhorn. Mimicry (Pseudoflowers) Mimicry (Pseudoflowers) Yellow pseudoflowers, mimic flowers and attract pollinators. Pollinator facilitates sexual reproduction in fungus. Puccinia monoica, plant pathogen induces pseudoflower formation. Bird’s Nest Fungi Dispersal Bird’s Nest Fungi Dispersal Common name from its Peridioles (eggs) resemblance to a bird’s nest. Peridium Peridiole contains Cyathus pallidus basidiospores and is the unit that is dispersed 9 Bird’s Nest Structure Bird’s Nest Structure Bird’s Nest Structure Peridiole Dispersal Rain drop Rain drop Peridiole Dispersal Peridiole Dispersal Peridiole Funicular cord wraps Funicular cord wraps around nearby plant. completely around substrate. 10 Bird’s Nest Fungi Dispersal Animal Dispersal Once attached, peridiole can Some puffballs are buried grow on attached substrate. underground and do not have an obvious mechanism for Also may be consumed by dispersal. foraging animals. These fungi are typically dug up Peridiole passes through by animals and taken elsewhere animal’s digestive system to be eaten and later dispersed unharmed. Animal Dispersal Animal Dispersal Rhizopogon: An example of a Tuber sp.: The “Truffle” is probably common puffball that is probably the most famous example of a dispersed by foraging animals. fungus that is animal dispersed. 11.