Cryopreservation of air-dried conidia of Uncinula necator

Conidia of Uncinula necator, the causal agent of grapevine powdery mildew, were viable after storage at -70 degrees C for up to 12 months following ai r drying without cryoprotectants, as determined by ability to infect surfac e-sterilised, detached grapevine leaves. The fungus was stored as cyclone-h arvested conidia and on segments of infected leaves. Conidia also survived five freeze/thaw cycles. Southern blot analysis revealed that DNA extracted from colonies resulting from cryopreserved and fresh conidia produced the same DNA fingerprints.