REUVENI, R., Division of Plant Pathology, Haifa post 31–999, Israel
RAVIVM, M., Division of Ornamental Horticulture, Agricultural Research Organisation, Newe-Ya'ar Experiment Station, Haifa, 31-999, Israel
BAR, R., Ginegar Plastic Co., 30053, Israel

Sporulation of Botrytis cinerea was studied in vitro under various filters and polyethylene co‐polymer (PE) sheets. It was found that continuous darkness blocked sporulation completely. Sporulation was inhibited by reduced ultraviolet (u.v.) radiation. Almost total inhibition of sporulation was also found when cultures were grown under a blue filter. The reduction of spore formation was negatively related to the ratio of transmitted blue/u.v. light. The possibility of using this effect to control the incidence of Botrytis cinerea in greenhouses is discussed. A brief report has been published (Reuveni, Raviv, Allingham & Bar, 1988). Copyright © 1989, Wiley Blackwell. All rights reserved