11 Jul 2001 14:56 AR AR138-06.tex AR138-06.SGM ARv2(2001/05/10) P1: GJB Annu. Rev. Phytopathol. 2001. 39:103–33 Copyright c 2001 by Annual Reviews. All rights reserved BIOLOGICAL CONTROL IN GREENHOUSE SYSTEMS Timothy C. Paulitz USDA-ARS Root Disease and Biocontrol Research Unit, 363 Johnson Hall, Washington State University, Pullman, Washington 99164-6430; e-mail:
[email protected] Richard R. Belanger´ Departement´ de Phytologie, Universite´ Laval, Ste. Foy, Quebec,´ Canada G1K 7P9; e-mail:
[email protected] Key Words biological control, Pythium root rot, powdery mildew, Pseudomonas, Trichoderma, Pseudozyma flocculosa ■ Abstract The controlled environment of greenhouses, the high value of the crops, and the limited number of registered fungicides offer a unique niche for the biological control of plant diseases. During the past ten years, over 80 biocontrol products have been marketed worldwide. A large percentage of these have been developed for green- house crops. Products to control soilborne pathogens such as Sclerotinia, Pythium, Rhizoctonia and Fusarium include Coniothyrium minitans, species of Gliocladium, Trichoderma, Streptomyces, and Bacillus, and nonpathogenic Fusarium. Products con- taining Trichoderma, Ampelomyces quisqualis, Bacillus, and Ulocladium are being developed to control the primary foliar diseases, Botrytis and powdery mildew. The development of Pseudomonas for the control of Pythium diseases in hydroponics and Pseudozyma flocculosa for the control of powdery mildew by two Canadian research programs is presented. In the future, biological control of diseases in greenhouses could predominate over chemical pesticides, in the same way that biological control of greenhouse insects predominates in the United Kingdom. The limitations in formu- lation, registration, and commercialization are discussed, along with suggested future by Ondokuz Mayis Universitesi on 09/18/14.