10th INTERNATIONAL VERTICILLIUM SYMPOSIUM 16-20 ...

ATTEMPTS TO CONTROL VERTICILLIUM WILT ON OLIVESIN ISRAELTSROR (LAHKIM), 1* L., DAG 2 A., HAZANOVSKY 1 M., ZIPORI 2 I., BAR-ON 3N., PRIEL 3 N., TUGENDHAFT 3 Y. AND LAVEE 4 S.1 Dep. of Plant Pathology, Agricultural Research Organization, Gilat,Israel;2 Dep. of Fruit Tree Sciences;3 Kibbutz Revivim, Israel;4 Faculty of Agriculture, Hebrew University of Jerusalem, Rehovot, Israel.Verticillium dahliae represents one of the main limiting factors in intensivelyirrigated olive production in Mediterranean countries. Economic damage caused bythe disease has increased during the last twenty years, due to extensive irrigation andintercropping with V. dahliae-susceptible hosts, such as potato and cotton. The mostefficient means of controlling the disease is to simply prevent it. However, whenoutbreaks in the orchard do occur, it is necessary to look for potential ways tominimize the damage by reducing the disease. The objectives of the present studywere to evaluate soil and seedlings treatments and application of fungicides to reducethe disease.Field trials were conducted in an infested orchard located at Revivim in thesouthern part of Israel. Three types of trials were conducted in parallel. 1) Soiltreatment trial: soil solarization, solarization combined with cattle manure compost (6kg/m2), solarization combined with soy meal (2 kg/m2) and solarization combinedwith cabbage residues (5 kg/m2). 2) Fungicide treatment trials that involved injectionunder pressure into the tree trunks of: Miraz (prochloraz), Canon (phosphoric acid),TOG (8-hydroxyquinoline sulphate) and Bavistin (carbendazim). 3) Inoculating oliveseedlings at the nursery with mycorrihzae. The effect of these treatments is discussedin detail. Following the first two trials, however, the differences between treated treesand untreated control trees were not significant. With amendments of mycorrihzae istoo early to summarize. The major conclusion is that the best way to overcomeVerticillium wilt on olive is to prevent it, by avoiding planting on infested soil, byusing tolerant-resistant cultivars and by maintaining optimal management conditions.89