Birds, bees, and fruiting bodies

    Most fungi can reproduce sexually as well as asexually, and the false morel is no exception.  In the asexual life cycle, the mycelium produces spores called conidia in structures called conidiophores (right).  The spores then germinate into more mycelium.  Sexual reproduction is a little more interesting and produces the things we call mushrooms.  It usually only occurs when environmental conditions are bad.  An example of this is the black bread mold Rhizopus stolonifer.  It uses asexual reproduction when it is growing on bread because there is plenty of nourishment.  That is why we don't usually see mushrooms sprouting from pieces of moldy bread.

     Like most fungi, Gyromitra esculenta spends most of its life as a mycelium.  To reproduce sexually, the mycelium forms a fruiting body, a conspicuous mushroom that most people associate with fungi.  The false morel fruiting body consists of a short white stem and a large cap with many wrinkles and folds, and a chambered interior.  The purpose of the fruiting body is to lift spores into the air so they can be distributed by the wind. 
    The surface of the mushroom produces haploid (one set of chromosomes) spores in structures called asci,(pronounced ASS-eye) pictured above.  The asci are tube-shaped with a cap at the end, and they contain eight spores each.  All fungi in the ascomycota reproduce this way.  The picture above is a generalized ascus structure.  The spores of Gyromitra esculenta are different, however. 
    The false morel's spores are ellipse shaped, smooth, and have an oil drop at each end. (Below)  They can be anywhere from 18x10µm to 30x13.5µm.  When the spores mature the operculum at the end of the ascus rips open, and they are released forcibly into the air.  Sometimes a cloud of spores can even be seen rising from the mushroom. 
                 

    After spores are released, they land and germinate into a new mycelium.  The mycelium grows and branches while conditions are still good.  However, if the fungus can’t get enough nutrients, it starts to consider its own mortality.  It moves toward reproduction. 
    Two haploid mycelium fuse, but only the cytoplasms, not the nuclei.  This process is called plasmogamy.  When conditions are right, the new mycelium, called a dikaryotic mycelium, forms a fruiting body.  In the fruiting body, the nuclei fuse in a process called karyogamy and form a diploid cell.  Meiosis occurs, haploid spores are produced, and the life cycle starts again.  There is no way to know exactly when a fruiting body will pop up (Yet! Check when this site was updated).  However, it has been found that when nutrients are low and water is abundant, mushrooms are more apt to form.  A diagram of the life cycle is shown below.

                        
                                    Life cycle visual taken from lecture notes by Dr. Tom Volk
   
    Since the process is somewhat ambiguous, it is hard to say exactly when in the year the fruiting bodies will appear.  In the upper Midwest the season for false morels is April and May.  This depends heavily on environmental factors.  These factors also affect where morels can be found. 

    To learn about where these mushrooms are usually found and why, see the habitat page.

Pictures on this page taken from Wikipeida.com.

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