Development of a diagnostic PCR assay for Aeromonas hydrophila of hypophthalmichthys molitrix

A pair of specific primers was designed and synthesized according to 16S RNA gene sequences of Aeromonas hydrophila from GenBank.The specific DNA fragment of an Aeromonas hydrophila strain separated from dead disease hypophthalmichthys molitrix was amplified by using PCR.The PCR reaction condition was optimized and the specificity and sensitivity of this PCR method were tested.The results of specificity test indicated that this primer could amplify 680 bp specific DNA fragment from Aeromonas hydrophila and it had no cross-reactivity with Vibrio anguillarum,Vibrio alginolyticus,Vibrio parahaemolyticus,Aeromonas sobria,Edwardsiella tarde,Edwardsiella ictaluli and Streptococcus iniae.The sensitivity test indicated that 10pg DNA of Aeromonas hydrophila could be detected with this method.Therefore,the PCR method established in this study could be used to detect Aeromonas hydrophila of hypophthalmichthys molitrix rapidly,and it had important significance on the effective diagnosis and control of Aeromonas hydrophila.