First report of Xanthomonas campestris causing black rot of chard in Cuba.
In March 2016, leaves of chard (Beta vulgaris var. cicla) with blackened veins and v-shaped necrotic lesions on the leaf margins surrounded by yellow halos were collected from plants growing in the "Organoponico" (a system of urban organic agriculture) in Havana Province, Cuba. The symptoms were similar to those observed in black rot disease on cabbage. Based on cultural, physiological and biochemical characteristics as well as pathogenicity and molecular data (amplifying and sequencing of 16SrDNA and DNA gyrase subunit B genes), the causal agent was identified as Xanthomonas campestris. This is thought to be the first report of X. campestris in chard.