Loop-mediated isothermal amplification (LAMP) assays for the detection of abaca bunchy top virus and banana bunchy top virus in abaca

Abaca bunchy top virus (ABTV) and banana bunchy top virus (BBTV) are pathogens that infect abaca in the Philippines causing significant reduction in abaca fiber yield and quality. In this study, a sensitive loop-mediated isothermal amplification (LAMP) assay was developed for detecting ABTV and BBTV in abaca, Musa textilis Nee. Five primer sets were designed and tested to detect ABTV while three primer sets were designed and tested to detect BBTV. Out of which only one primer set for each virus was specific to their respective targets that is DNAN for ABTV and DNA-S for BBTV for successful LAMP based detection applications. The concentrations of Bst DNA polymerase, dNTPs, incubation time and temperature were optimized for both viruses using either GelRed (TM) or SYBR (TM) Green I as detection dyes. The ABTV and BBTV LAMP assays were more sensitive than conventional PCR and were able to detect ABTV or BBTV in asymptomatic abaca samples. The developed LAMP protocols provide a simple, fast and accurate detection method that will be indispensable for the production of ABTV- and BBTV-free abaca tissue cultured plantlets. This is the first report of a LAMP-based assay for detection of ABTV and BBTV in abaca.