STUDIES ON BIOLOGICAL CONTROL OF FIRE BLIGHT

Studies on biocontrol of fire blight (Erwinia amylovora) were undertaken with antagonistic bacteria under in vitro and field conditions.
Among 81 bacterial isolates from leaves and flowers of different fire blight host plants, 30 strains showed antagonistic activity against the pathogen when tested in a screening with agar-diffusion-test and in a bioassay on immature pear fruits.
In a field test with the highly susceptible ornamental Cotoneaster salicifolius floccosus prophylactic sprayments were carried out with different antagonists of the genus Erwinia, Pseudomonas and Bacillus against blossom blight.
With a strain of Erwinia herbicola the highest control of 70% in comparison to streptomycin with 73% could be obtained. E. herbicola was effective in all experiments whereas other isolates were more effective in vitro. In general some active isolates with very good bactericidal effects for the biological control of fire blight could be found, so that these studies will be continued.

VII International Workshop on Fire Blight

W. Zeller, B. Wolf

https://doi.org/10.17660/ActaHortic.1996.411.69