Effect of three antagonists on the development of bacterial leaf streak of rice

Among 11 epiphytic microorganisms one species each of Pseudomonas, Erwinia, and Aspergillus were antagonistic to Xanthomonas translucens subsp. oryzicola. Symptoms of bacterial leaf streak did not develop when the antagonists were sprayed on rice leaves 24 h before inoculation. Although the symptoms developed when the antagonists were applied 24 h after inoculation, the number of lesions and their length was significantly reduced over control. When the mixture of each antagonist and the pathogen was applied, no symptoms developed with Pseudomonas and Aspergillus sp. However, the symptoms could develop with Erwinia sp. although the number and length of the lesions was reduced over control.