Recovery of Olive Trees with Verticillium Wilt After Individual Application of Soil Solarization in Established Olive Orchards. E. C. Tjamos, Agricultural University of Athens, Laboratory of Plant Pathology, Votanikos 118 55 Athens, Greece. D. A. Biris, and E. J. Paplomatas. Plant Protection Institute, 380 01 Volos, Greece; and University of California, Department of Plant Pathology, Davis 95616. Plant Dis. 75:557-562. Accepted for publication 14 September 1990. Copyright 1991 The American Phytopathological Society. DOI: 10.1094/PD-75-0557.

Evidence was obtained suggesting that olive trees with Verticillium wilt (caused by Verticillium dahliae) could be recovered after soil solarization of individual 10- to 15-yr-old trees. Rate of recovery of trees in solarized soil significantly exceeded natural recovery of untreated control trees and was attributed to the lack of root reinfection. Microsclerotia of V. dahliae were nearly eliminated in the soil around treated trees, whereas propagules of Talaromyces flavus, a known antagonist of V. dahliae, not only survived solarization but also increased in treated soil, compared with untreated control soils. Because the differences in symptom remission or recovery persisted for at least three successive years, soil solarization of individual diseased trees, when combined with chemical weed control, could be of practical value in controlling Verticillium wilt of olive trees.