Figure 5

Pycnidia development progresses slowly in the mutant S. nodorum strains under study. Longitudinal sections of a wax embedded excision of a S. nodorum gga1- 25 culture -stained with toluidine blue, is pictured. Slow differentiation of mycelia into pycnidia allowed all stages of development to be captured in an excision from a single culture. Pynidia formation begins with the intertwining of mycelia to form a mycelial knot (A), which is followed by differentiation and enlargement of the cells (Ec), forming a primordium (B through F), which matures into the pycnidium (G), eventually producing pycnidiospores from the conidiogenous cells (Cv) within the pycnidial cavity.