Evaluation Of PCR-Based Protocols For The Detection Of Acidovorax Citrulli

Bacterial fruit blotch (BFB) of cucurbits is a destructive disease caused by the Gram-negative bacterium Acidovorax citrulli which has harmed cucurbit industry destructively. Acidovorax citrulli is a seedborne pathogen and accurate diagnosis approaches of Acidovorax citrulli are crucial for plant quarantine agencies to facilitate early detection and incursion management. Currently molecular techniques such as PCR are routinely used for the detection of plant disease and especially useful for the seedborne pathogen. Many conventional PCR protocols have been devised to detect and identify Acidovorax citrulli while the most widely-used PCR protocol-WFB1/2which is targeted16SrDNA region was reported to having some false positive results in Acidovorax citrulli’s counterfeit species. The specificity and sensitivity of conventional protocols for the detection of Acidovorax citrulli haven’t been compared comprehensively. A collection of72geographically diverse bacteria which were closely related to Acidovorax citrulli and63genetically diverse strains of Acidovorax citrulli were used to test seven published conventional specific-PCR prime protocols. The result had shown that only the protocol BX-SL1R/S-R2which is targeted repetitive extragenic palindromic named BOX element attained the requirements of specificity for structural inspection in this study; two protocols which are targeted16SrDNA region had3false positive amplifications in Acidovorax citrulli’s counterfeit species, and3or4false negative amplifications respectively; two protocols which are targeted ITS region were protocols Aacf2/r2and protocol SEQID4/5, the protocol Aacf2/r2had6false positive amplifications in Pseudomonas syringae and5false negative amplifications while the protocol SEQID4/5had none positive amplification and3false negative amplifications; two protocols which are targeted TRAP dicarboxylate transporter region were protocols RST49/51and Seminis WFB1/2which were both had false positive amplification in Acidovorax avenae snbsp.avenae, the protocol RST49/51had6false negative amplifications while the protocol Seminis WFB1/2had10false negative amplifications. While using inaccurate prime protocols as the disease detection standard would misinterpret detection result. Relatively, prime protocol BX-SL1R/S-R2is suitable for the detection of Acidovorax citrulli, besides it didn’t have any false negative or false positive result makes its more fit for the Acidovorax citrulli-specific PCR-based detetion. And this research showed that the application of repetitive extragenic palindromic used in the detection of plant pathogen should get noticed.