SYRINGOMYCIN-E PRODUCED BY BIOLOGICAL-CONTROL AGENTS CONTROLS GREEN MOLD ON LEMONS

Pseudomonas syringae strains ESC-10 and ESC-11 suppressed green mold o f citrus, caused by Penicillium digitatum. In this paper, we demonstra ted that strains ESC-10 and ESC-11 produced syringomycin E in vitro wh ich was inhibitory to Geotrichum citriaurantii, Penicillium digitatum, and Rhodotorula pilimanae. Purified syringomycin E from strains ESC-1 0 and ESC-11 controlled green mold on lemons to the same extent as it did the bacteria when syringomycin E was applied to wounds at 1000 tim es the concentration needed for in vitro inhibition of Penicillium dig itatum. Syringomycin E may be involved in biological control of green mold on citrus by strains ESC-10 and ESC-11.