Citrus Canker Approaching Century: A Review

摘要

Citrus canker was recognized in 1912 in Florida, USA, and it became so severe that mass eradication of diseased plants was undertaken in the United States to prevent further spread. The campaign to eradicate citrus canker in the USA began in 1915 andthe disease was declared eradicated from these areas by 1947. The pathogen originated in the tropical areas of Asia, such as South China, Indonesia and India, where Citrus species are presumed to have originated. The disease is presently prevalent in Africa, Asia, Australia, Oceania and South America. Citrus canker causes heavy losses when the infection occurs at early stages of plant growth. The causal bacterium, Xanthomonas axonopodis pv. citri (Hasse) Vauterin, has three distinct forms (A, B and C) based on geographical distribution and host range. This review focuses primarily on historical developments of canker disease, host-pathogen interactions, variability, and latest achievements in the management of the disease though quarantine, cultural means, resistance sources, biocontrol techniques and biotechnological approaches. It also takes stock of the situation where restricted chemicals are still being used in some countries for managing the disease and will be a source of information for researchers and extension workers.