Induced Suppressiveness in Solarized Soils

Publisher Website
Google Scholar
Abstract
The fate of inoculum added to untreated or previously disinfested soils and disease incidence in these soils were investigated. In most of the solarized soils tested, disease incidence was lower than in the comparable untreated soils, as shown with bean plants in soils infested with Sclerotium rolfsii and tomato seedlings inoculated with Fusarium oxysporum f. sp. lycopersici. The incidence of Fusarium wilt of tomato was also lower in artificially heated soil but higher in one out of 10 solarized soils and one out of two soils fumigated with methyl brumide. In solarized soils, chlamydospore formation by F. o. f. sp. lycopersici was suppressed. In these soils, populations of lysing bacteria of S. rolfsii frequently increased, and fungistasis to this pathogen decreased, proportionally to the level of fungistasis in untreated soils. Establishment of F. o. f. sp. lycopersici was better in soils preheated to temperatures above 75 C. Solarized soils are frequently more suppressive and less conducive to certain soilborne pathogens than nonsolarized soils.