FIG. 7.

Electron micrographs of stuA and medA mutants. In the stuA mutant, abnormal conidia are formed either directly from the conidiophore vesicle (A) or from abnormal sterigmata (B and C). Normal metula and phialides are not produced. medA mutant conidiophores are initially nearly normal, but multiple layers of metulae are produced before phialides differentiate and begin to form conidia (D and E). Sometimes sterigmata redifferentiate to produce secondary conidiophores (F). Reproduced from reference 6 with permission of the publisher.