SOIL SOLARIZATION FOR THE CONTROL OF PHYTOPHTHORA CAPSICI ON PEPPER

Experimental trials were carried out in Calabria (Italy) from 1991–1992 to evaluate the effect of soil solarization in controlling Phytophthora capsici. Disease incidence was low (2.2 – 2.9 %) in a plastichouse covered since July 1991, either in solarized or non mulched soil with transparent polyethylene sheet, while it rose from 19.5 % to 80.1 % in the control plastichouses covered before transplanting (March 1992). In the tests carried out in February 1992, a dilution-plate technique using P₅VPP-BH selective medium indicated that infective propagules were detectable only in control plastichouses. The density of the initial inoculum of P. capsici was not directly related to disease incidence. In fact low densities of inoculum induced a high percentage of infected plants. A delay in infections (4–9 weeks) was observed in the treated plastichouse (solarized and non mulched). Data on average height, dry and fresh weight, yield increase of pepper plants are also reported.