Betty J. Jeffers
Project Topic / Abstract:
"Comparative Peridium and Spore Morphology in Bird's Nest Fungi (Nidulariaceae) and its Relation to Spore Dispersal Mechanisms"
Nidulariaceae, or bird's nest fungi, contain their
basidiospores in numerous lenticular-shaped peridioles. The
peridioles are in turn contained within a larger peridium,
or fruiting body, that ranges in shape among the five genera
of bird's nest fungi. Although peridium structure plays an
influential role in the mechanisms of spore dispersal,
little is known about the morphological basis for this. In
the present study, two species of Nidulariaceae were
examined using combined light microscopy and scanning
electron microscopy. Cyathus stercoreus has a rigid,
vase-like peridium, whereas that of Nidularia pulvinata is
more fragile and globose. This investigation focused on the
ultrastructural differences between the two species
regarding the morphology of mature peridia and peridioles,
the initiation of peridiole development, and the presence or
absence of both modified clamp connections and a funicular
cord, which functions in spore dispersal. This study also
documented morphological correlations between these
structural features and the different methods of spore
dispersal in the two species. For example, the vase-like
peridium of C. stercoreus functions as a splash-cup,
ejecting the peridioles and their attached funicular cords.
These cords act as "grapling hooks" during dispersal. By
contrast, the globose peridium of N. pulvinata does not
facilitate the ejection of peridioles, which lack funicular
cords. Here, the relatively thin-walled peridium simply
disintegrates and passively releases the enclosed peridioles.
In addition, this is the first study to examine a special
case of twinning in N. pulvinata.
Presentations:
1997 National Conference on Undergraduate
Research (Austin, TX)
1997 Truman Undergraduate Research
Symposium (Kirksville, MO)
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