GFP-PMK1 was highly expressed in developing conidia. When blocks of Xh14 oatmeal cultures were examined in situ by epifluorescence microscropy, a strong fluorescence signal was observed in young developing conidia. Conidiophores bearing young conidia were also fluorescent, but the signal was much weaker. Mature conidia exhibited only weak fluorescence. CP, conidiophore; YC, young conidium; MC, mature conidium. Bar = 10 μm.