Ultrastructure of Urediniospore Development in Coleosporium ipomoeae as Revealed by High‐Pressure Freezing Followed by Freeze Substitution

Autor: Elizabeth A. Richardson, Charles W. Mims
Rok vydání: 2005
Předmět:
Zdroj: International Journal of Plant Sciences. 166:219-225
ISSN: 1537-5315
1058-5893
DOI: 10.1086/427199
Popis: Transmission electron microscopy of high‐pressure frozen/freeze‐substituted samples was used to study urediniospore development in Coleosporium ipomoeae in leaves of Ipomoea coccinea. The urediniospores of this species are morphologically identical to aeciospores. Our study showed that these spores developed in the same fashion as aeciospores. Spores formed in a basipetal fashion along with intercalary cells from a layer of binucleate sporogenous cells lining the base of each uredinium. High‐pressure freezing/freeze substitution yielded excellent preservation of ultrastructural details of the spore formation process until the point of secondary wall formation in maturing spores. When viewed with scanning electron microscopy, mature urediniospores were verrucose in appearance, except for a slightly reticulate area at the base of each spore. Both the reticulations and the small wartlike ornaments present on spore surfaces arose from tiny electron‐transparent deposits that formed on the outer surface of the ...
Databáze: OpenAIRE