Figure 5. Germination of WT and Δpah5 ascospores.

Ascospores were incubated for 6 h at 27°C on germination medium and observed by light microscopy. A. WT ascospores from a WT mat+ × WT mat− cross are melanized and germ tubes originate from a germination peg (*) located at the pole opposite to the primary appendage (arrowhead). B. Δpah5 ascospores from a trikaryotic culture (see Results) are not fully melanized and germ tubes appear at both poles (arrow points at the germ tube originating from the primary appendage (*)). Numerous Δpah5 ascospores did not germinate even after incubation for several days.