Urediniospores (or uredospores) are thin-walled spores produced by the uredium, a stage in the life-cycle of rusts.
Development Urediniospores develop in the uredium, generally on a leaf's under surface.
Morphology Urediniospores usually have two dikaryote nuclei within one cell. In mass they are usually pale brown in contrast to teliospores which are generally dark brown.
See also
Chlamydospore Urediniomycetes Pycniospore Aeciospore Teliospore Ustilaginomycetes Rust fungus: Spores
References C.J. Alexopolous, Charles W. Mims, M. Blackwell, Introductory Mycology, 4th ed. (John Wiley and Sons, Hoboken NJ, 2004) ISBN 0-471-52229-5