Variability of germinative potential among pathogenic species of Aspergillus

The objective of our study was to evaluate parameters influencing the germination of Aspergillus conidia. Inoculum concentration and age significantly influenced germination. Different incubation temperatures revealed significant differences among Aspergillus species. The internal human milieu provides the ideal conditions for the development of invasive disease by Aspergillus fumigatus but restricts invasion by Aspergillus flavus and Aspergillus niger. Aspergillus spp. are ubiquitous organisms, progressively as-sociated with a growing spectrum of infections in immunocom-promised hosts (9, 11). Aspergillus fumigatus is responsible for over 90 % of cases of invasive aspergillosis (7). Germination of conidia is the most crucial step in the de-velopment of Aspergillus, as hyphae represent the invasive form (4, 8). Thus, germination rate and hyphal growth represent good indicators of interspecies variability and may be useful in designing potential antifungal compounds (10). Several studies have reported higher MICs for a hyphal inoculum than for