PCR BASED MOLECULAR CHARACTERIZATION OF CITRUS BACTERIAL CANKER FROM GRAPEFRUIT (CITRUS PARADISI)

Citrus bacterial canker (CBC) occurs due to Xanthomonas axonopodis pv. Citri (Xac) is a pathogenic bacteria. It was first reported in Japan, USA and many areas of India in 19th century. Synchronized by the spread of the causative agent the diversity of labelled pathogen continues to spread with new strains appearing in many other regions of the world. However, its diagnosis is quite difficult due to its symptoms similarity with other bacterial strains. This piece of study was designed to identify Xanthomonas axonopodis using polymerase chain reaction (PCR). PCR is more accurate, precise and fast method which is used for detection and quantification of many bacterial species. Two primers Xac01 and Xac02 were used for PCR based CBC detection. These primers were based on rpf gene region which give very specific results in Xac identification and can separate two much similar bacterial strains. There is another Primer pair designed on the pthA gene which act as universal primer and usually used for detection of all varieties of citrus canker bacteria. Leaves sample from different infected Citrus paradisi plants were collected for further analysis. Results confirmed that three samples among five have CBC. It is concluded that using PCR we can detect citrus canker disease more specifically which will help in discovering new eradication methods for its control.