MicrobeLibrary - Endomycorrhizae

Mycorrhizae literally means fungal root and describes a beneficial relationship between fungal microorganisms and higher plants. Endomycorrhizae produce hyphae (thread-like nonreproductive filaments) that penetrate cortical cells (cells between the vascular bundles and the epidermis of plant roots) producing exchange structures (arbuscules) and storage structures (vesicules). Most land plants have these associations, but one must stain the roots to determine colonization. The external appearance of roots is the same to the unaided eye whether colonized or not colonized. The nonseptate (hyphal filaments without crosswalls) Zygomycetes are the class of fungi involved in these associations. Better understanding of these associations is important in low-input agricultural systems where natural biological processes can provide needed plant nutrition. Root samples were collected and stained with trypan blue or acid fuchsin to observe internal structures at different magnifications. A downloadable, high-resolution version of this movie in RealMedia format is available at http://www.agron.iastate.edu/~loynachan/mov/.

References.

1. Paul, E. A. (ed). 2007. Soil microbiology, ecology, and biochemistry, 3rd ed. Academic Press, Oxford, United Kingdom.

2. Sylvia, D. M., J. J. Fuhrmann, P. G. Hartel, and D. A. Zuberer. 2005. Principles and applications of soil microbiology, 2nd ed. Pearson Prentice Hall, Upper Saddle River, N.J.