Survival of Xiphinema index in clay loam soil

A sample of clay loam vineyard soil, containing the nematode Xiphinema index, was divided into equal portions and stored in plastic bags. Nematodes were extracted immediately or remained in fridge for a short time or at room temperature for longer periods. The number of extracted nematodes did not differ significantly between treatments, indicating that X. index in soil samples collected for diagnostic purposes could remain viable for a period up to six months. Four other samples, of similar soil type, were collected from different vineyards and kept stored in plastic bags at room temperature. Variable periods of nematode survival recorded, ranging from less than two years in one sample, up to five years in another one. It is concluded that a long fallow period of at least five years may be required between successive grapevine crops to eliminate the nematode from clay loam soils.