Abstract
The aim of the INDICANTS project is to develop innovative diagnostics for four banana wilt pathogens, including Fusarium oxysporum f. sp. cubense (Foc) TR4 (Fusarium wilt), Ralstonia solanacearum (Moko disease), R. syzygii subsp. celebesensis (Blood disease), and Xanthomonas vasicola pv. musacearum (Xanthomonas wilt). The main objectives are to: (I) develop low-cost LAMP (loop-mediated isothermal amplification) assays (II) compare simplified DNA extraction methods for field application; (III) validate the LAMP protocols via inter-laboratory and field tests. LAMP primer sets were designed for the bacterial pathogens, using in silico comparative genomic analysis of target and non-target genomes, and showed 100% specificity when tested with a wide range of target and non-target strains. A limit of detection of 104 CFU/ml was obtained for the LAMP assays. A simplified DNA extraction method from banana tissue was developed and successfully validated in a banana plantation infested with Foc TR4, using several candidate LAMP primer sets. Ready-to-use diagnostic kits, based on these protocols, are currently being developed by a private company. These point-of-care diagnostic tools will allow rapid identification of the different pathogens in the field for disease management.