Reliable detection of the fungal pathogen Fusarium oxysporum f.sp albedinis, causal agent of Bayoud disease of date palm, using molecular techniques

Bayoud, caused by the soilborne fungus Fusarium oxysporum f.sp. albedinis ( FOA), is the most serious disease of date palm. Since the disease is locate d in the North African countries of Morocco and Algeria, and advancing stea dily eastwards, the ultimate goal is to prevent spread of the pathogen to o ther date-growing areas in the region and farther afield. Molecular diagnos tic techniques have been developed for detection of FOA. In view of the fac t that the fungus does not exist in Israel, DNA of FOA was obtained to dete rmine the reliability of these methods for diagnostic purposes. Random ampl ified polymorphic DNA was not reliable enough for differentiation between F OA and various pathogenic and saprophytic Fusarium isolates. However, the p olymerase chain reaction utilizing FOA-specific primers was accurate and en abled amplification of a unique band specific to FOA DNA alone, and not tha t of the other tested pathogenic and saprophytic Fusaria. The availability of a rapid and reliable diagnostic tool for detection of FOA will enable th e Plant Protection and Inspection Services of the Israel Ministry of Agricu lture to test date palm tissue for the presence of the pathogen.