Evaluating Thirty-Four Grape Rootstocks for Resistance to Root-knot Nematode Strains

Grape rootstocks with broad resistance against nematodes and other soils pests, combined with the ability to produce high quality fruit, are greatly needed. Thirty-four grape rootstocks were screened for resistance to Meloidogyne incognita Race 3 (Chitwood 1949) under greenhouse conditions. Resistance was evaluated by counting egg masses on the roots after staining with eosin dye. The genotypes 043-43, 10-17A, 10-23B, 101-14Mgt, 1103P, 1447P, 1616C, 6-19B, Boerner, Dog Ridge, Freedom, Harmony, K51-32, 5BB, and Ramsey were resistant to M. incognita Race 3. These rootstocks were then screened for resistance under the same conditions to 50/50 mixture of a M. arenaria and a M. incognita strain selected for their ability to feed on Harmony and Freedom. The genotypes 10-23B, 1616C, 043-43, 99R, 10-17A, Bogner, 101-14Mgt, and Ramsey were resistant to this mixed inoculum.