Citrus fruits aren’t too easy to decay. They have thick rinds that’re chock full of aromatic essential oils that suppress most fungi. They’re alive, and can activate various defense responses to thwart invaders. Enter Penicillium digitatum, a mold that specializes in Citrus. It’d be hard to get away with saying this one’s lovely, eh? But it has a certain charm, at least in time lapse video. This lemon, which we cruelly inoculated with the mold of doom, took about 7 days to complete its act. Since we lack smell-o-vision, you’ll just have to imagine the stink of a fully rotted lemon. A memorial piece of it now resides in our Herbarium as CUP 067576. You can never have too much rotted citrus in your herbarium.
Quicktime 5+ movie
Time lapse video by Kent Loeffler
DIYers: You may have already done this experiment at home! Buy a lemon that has a water-soaked looking bruise. Take it home, and wait. Chances are good you’ll find either Penicillium digitatum (green rot) or its arch enemy, Penicillium italicum (blue rot). Look out, little lemons!