A Test of Vitis Resistance to Xiphinema Index

Abstract

Techniques are described for testing the resistance of rooted grapevines in the greenhouse to the ectoparasitic nematode Xiphinema index . Resistance ratings are based upon both visible root symptoms and the change in population of nematodes on the roots of the test plants over an inoculation period of eight months. It is possible to assign the degrees of resistance possessed by different Vitis species. Resistance was highest in V. candicans, V. solonis, V. arizonica, V rufotomentosa , and V. smalliana . Among commercial rootstocks, 9Solonis9 X 9Othello9 1613 showed moderate resistance, all others tested were quite susceptible (including V. vinifera ).