Studies to Determine the Causal Agents of Soil-borne Fungal Diseases of Strawberries in Aydin and to Control them by Soil Disinfestation

This study was aimed to determine the causal agents of soil-borne fungal diseases that pose a threat to the strawberry production in Aydin, Turkey and to investigate the potential effects of solarization and three fumigants (metam sodium, dazomet and methyl bromide) on these diseases. As the agents of the diseases, Rhizoctonia solani Ku¨ hn. Phytophthora cactorum (Lebert and Cohn) J. Schro¨ t., Verticillium dahliae Kleb. were detected. Trials to determine the effects of solarization and the fumigants were conducted in two successive cropping seasons of strawberries. Soil temperatures at 0, 10 and 20 cm depth of solarized and unsolarized plots were measured. In 1998–99, soil solarization gave significantly better control of the diseases than fumigants and the highest yield of 59 tons/ha was obtained from the solarized plots. This is followed by dazomet (50 g/m2) treated plots with the yield of 34.4 tons/ha, while non-treated control plots yielded 22.4 tons/ha. In 1999–2000, all treatments gave higher yields than non-treated control plots (26.1 tons/ha), but there were no difference (P < 0.05) among the treated plots where the yields varied between 33.3 and 36.1 tons/ha