Antagonism of isolates of Trichoderma spp. at egard of Botrytis cinerea pers. agent of gray rot of tomato (Lycopersicum esculentum Mill.) under greenhouse

The study of the antagonistic activity eleven isolates Trichoderma spp., against four Botrytis cinerea, collected from diseased tomato plants cultivated in greenhouses located on Algiers coast and north-east Sahara. vitro antagonism was compared to fungicidal "PROLEX", widely used by farmers this phytopathogen Algeria. results revealed a complete inhibition sporulation, germination, production germination sclerotia as well morphological changes vitro. A significant reduction their pathogenicity strong sporulation were recorded vivo. In conclusion, spp. antagonists particular, "T4, T11, T8 T10" are therefore promising for biocontrol grey mould tomato.