In vitro studies on fire blight control by bacterial antagonists

摘要

Both biological and chemical control agents for management of fire blight (Erwinia amylovora) areapplied during blossom blight phase, which is considered as a key point in the management of thisdestructive disease of pome fruits. Prevention of blossom infections should lead to interruption of thedisease cycle [2,7]. Biological control methods as application of antagonistic microorganisms [1,6,10] are alternativemethods to the use of the controversal antibiotic streptomycin sulfate. Pantoea agglomerans (P. a.) is theagent of the biological control product Blossom Bless. The objectives of the present studies were 1) theisolation of E. amylovora suppressive bacteria, especially P. agglomerans, from fire blight host plants inAustria and 2) the comparison of four agar diffusion tests for their suitability for rapid in vitro screeningfor antagonistic bacterial isolates.