Bacterial Exudation from Lesions of Asiatic Citrus Canker and Citrus Bacterial Spot

When water was added to wells surrounding young lesions of Asiatic citrus canker (caused by Xanthomonas campestris pv. citri) on detached, field-collected leaves of grapefruit, about 10 4 -10 5 bacteria per milliliter were exuded immediately. Bacterial exudation into the water continued at high levels for 24 hr, and cumulative release ranged from 10 5 to 10 6 per lesion. Fewer bacteria were exuded and bacteria were exuded more slowly from old lesions than from young lesions. Bacterial exudation from lesions of citrus bacterial spot (CBS) produced by X. c. pv. citrumelo on grapefruit and Swingle citrumelo was substantially less than that from Asiatic citrus canker lesions (.)