Citrus canker: Is a disease caused by

Citrus canker is a disease caused by the bacterium Xanthomonas citri subsp. citri (synonym X. axonopodis pv. citri). It thrives in areas with high rainfall and warm temperatures. Citrus canker is found throughout Florida and in limited areas of Alabama, Louisiana, and Texas. Citrus canker is a ravaging bacterial disease threatening citrus crops. Its major types are Asiatic Canker , Cancrosis B, and Cancrosis C, caused by Xanthomonas citri pv. citri (Xcc), Xanthomonas citri pv. aurantifolii pathotype-B (XauB), and pathotype-C (XauC), respectively. In canker , leaves are not distorted. Lesions are typically circular with yellow halo; appear on both sides of leaf, severe in acid lime (difference from scab) When lesions are produced on twigs, they are girdled and die. On fruits, canker lesions reduce market value. Disease Cycle of Citrus Canker : Bacteria gain entrance to the host through stomata, lenticels, and wound. They perennate in the affected host tissue. The inoculum is disseminated by wind rains and sometimes by insects. But the disease is commonly disseminated through infected nursery stock.