Suitability of membrane-filter techniques to study the ultrastructure of Fusarium solani in soil.

The suitability of two types of membrane filters for scanning and transmission electron-microscopical examination of chlamydospores formed from macroconidia of Fusarium solani from soil was tested. An improved method to incubate propagules in soil and to collect them free from soil particles for electron-microscopical observations is described. Best results were obtained if macroconidia were incubated in soil between two Nucleopore membrane filters. Both chlamydospore morphology and lysis, however, were affected to some extent in comparison with that on single membranes. This is probably due to a selective effect on the microflora colonizing the chlamydospores.