Root rot is considered one of the serious widely spread tomato diseases in plastic houses culture of Syria. Soil solarization, using transparent polyethylene (PE) covering, was applied during July and August (١٩٩٤-١٩٩٦) in Tartoos governorate for controlling soilborne pathogenic fungi. Results indicated that, native fungal populations in covered moist soil supplied with or without sulfur were significantly reduced in comparison with the uncovered treatment.