Simple techniques suitable for long-term storage of Plasmopara viticola

Summary. Propagules of Plasmopara viticola or fragments of P. viticola infected host tissue were stored by three techniques, freezing at –25°C, dehydration with CaCl2, and freeze-drying. Viability tests were performed periodically until exhaustion of the testing sample. P. viticola samples that were frozen at -25°C remained viable for eight years, whereas the CaCl2 dehydrated samples remained viable for eight and a half years. Freeze-drying was the most successful long-term storage method, being able to preserve samples for almost 21 years.