Plant pathogens often cause disease through protein effectors, a case in point being the fungus Botrytis cinerea. Arne Weinberg of the University of California at Riverside and colleagues have now elucidated the exact mechanism. The fungus infects tomatoes and strawberries, causing grey mold, and is also the "noble rot" that is essential in the production of desert wines like Sauternes. The researchers have found that it uses small RNAs (sRNAs), typically 20 to 24 nucleotides long, to disrupt plant cell functions. More than 800 sRNAs are produced by Botrytis – a remarkable fact to contemplate over some Chateau d’Yquem.