Abstract: Based on the establishment of the optimal PCR and RT-PCR for the detection of single virus，a multiplex PCR protocol for the detection of three main viruses (Banana bunchy top virus，BBTV；Cucumber mosaic virus，CMV；Banana streak virus，BSV) in banana is developed. Three specific fragments with molecular weights at 615 bp for BBTV，480 bp for CMV and 945 bp for BSV were simultaneously amplified in one PCR reaction system. The sequence analysis of amplified fragments indicates that three virus fragments shared above 91 percent identities with that of other relative viruses. It was showed that the sensitivity of this protocol equaled to be able to detect the three viruses at the level of 10-2 mg banana tissue.

Key words: banana, virus, Cucumber mosaic virus, Banana bunchy top virus, Banana streak virus, multiplex PCR