Xanthomonas hortorum campestris vitians

Bacterial leaf spots is a disease affecting lettuce plants caused by Xanthomonas campestris pv. vitians, recently reclassified as X. hortorum pv. vitians [74]. This disease does not normally produce severe losses [75], but outbreaks occur during periods of heavy rainfall [76]. The leaves of infected plants show translucent, water-soaked brown lesions that become dark with age. These types of symptoms, and the fact that the bacterium is generally not isolated from the chlorotic halos surrounding the dead tissues, suggest the involvement of toxic compounds in the disease developments. Two phytotoxic metabolites were isolated from the culture filtrates of X h. pv. vitians, which were identified as 3-methylthiopropanoic and -methylthiopropenoic... 

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