Category: Archived

#143: <em>Boletinellus merulioides</em>, the Ash Tree Bolete [Archived] 0

#143: Boletinellus merulioides, the Ash Tree Bolete [Archived]

Boletinellus merulioides is an odd mushroom, both in appearance and ecology. The Ash Tree Bolete can be readily identified by its pore surface – which is only a few millimeters thick and looks more like a network of ridges – and by the fact that it fruits only under ash trees.  merulioides appears under ash because it has a unique symbiotic relationship with a pest of ash trees: the Leafcurl Ash Aphid.

#049: Coffee Rust [Archived] 1

#049: Coffee Rust [Archived]

Coffee Rust (la roya in Spanish) is a disease of coffee plants that is caused by the fungus Hemileia vastatrix. If you enjoy a fine cup of coffee, then this is one fungus you should be very interested in.  The Coffee Rust is currently ravaging coffee trees in Central America, where 60% to 75% of the region’s crops are infected with the pathogen.  The result of this has been a 15% drop in Central America’s coffee output and a corresponding loss of more than 100,000 jobs over the last two years.  The high-end Arabica trees are particularly susceptible to the disease.  America’s major coffee producers have been able to find enough coffee to meet demand without a noticeable impact on price*, but smaller, specialty brewers are having a harder time.  And we haven’t seen the worst of it yet: the United States predicts that Central American coffee production could fall...

#027: Mushroom Morphology: Gilled Mushrooms (“Agarics”) [Archived] 4

#027: Mushroom Morphology: Gilled Mushrooms (“Agarics”) [Archived]

The gilled mushrooms, informally referred to as “agarics,” are the type of mushroom with which we are most familiar. The most common edible mushrooms (white/button/portabella mushrooms, oyster mushrooms, and shiitake mushrooms) are all gilled mushrooms.  Amanita muscaria, the most recognizable mushroom in the world and the inspiration for Mario-style mushroom art, and the “magic mushrooms” are also gilled mushrooms.  What all of these mushrooms have in common is a hymenium (spore-bearing surface) that is separate from the sterile, upper part of the fruiting body (the cap/pileus) and that forms “gills.”  Gills (known to mycologists as “lamellae”) are plates of spore-producing tissue that form perpendicular to the pileus and radiate out from a single point.  The shape of these plates of tissue is reminiscent of fish gills, resulting in the term “gills.”  This morphology has apparently been highly successful among mushrooms.  If you pick up any field guide to mushrooms, agarics...

#015: Characteristics of Phylum Glomeromycota [Archived] 1

#015: Characteristics of Phylum Glomeromycota [Archived]

The Glomeromycota are all fungi which form arbuscular mycorrhizae (AM). Mycorrhizae are a type of mutualism with plants where the fungus gets sugars and gives up hard-to-extract nutrients (especially phosphorous).  AM fungi accomplish this by forming structures within the plant’s root cells while not causing a disease reaction.  Most land plant species form AM, and only a few families are considered non-mycorrhizal.  AM fungi tend to be generalists, colonizing a variety of different plant species.  Each plant is usually colonized by multiple AM species.  This mycorrhizal network has a variety of different roles in an ecosystem.  It supplies nutrients to plants, determines what species make up an ecosystem’s plant community, and allows other plants (like orchids and Indian pipe) to parasitize larger plants via the network.  A recent study has also suggested that plants use AM fungi to communicate with their neighboring plants.  For more on AM, see FFF#074.  Only...

#013: Characteristics of Phylum Basidiomycota [Archived] 18

#013: Characteristics of Phylum Basidiomycota [Archived]

Phylum Basidiomycota accounts for about 35% of all described fungal species.* This phylum contains the fungi that people are most familiar with. The classic “Mario mushroom” (based on Amanita muscaria), the grocery store button mushroom and other varieties of Agaricus bisporus, shiitakes, oyster mushrooms, and even the major “magic mushrooms” are all basidiomycetes.  However, basidiomycota also includes rusts and smuts, which are economically important plant pathogens, some yeasts, and a few lichenized fungi.  Like the ascomycota, the basidiomycota fill a variety of different ecological roles.  Many form mycorrhizae with plants (amanitas, chanterelles, russulas, etc.), others parasitize plants (rusts, smuts, honey mushrooms, etc.), a lot decompose organic material (cultivated mushrooms, yeasts, etc.), and some live in a variety of symbioses with insects (this includes some interesting mutualisms with leaf cutter ants and termites).