Rapid detection of the Fusarium oxysporum lineage containing the Canary Island date palm wilt pathogen

Fucsarium oxysporum f. sp. canariensis causes Fusarium wilt disease on the Canary Island date palm (Phoenix canariensis). To facilitate disease manage ment, a polymerase chain reaction diagnostic method has been developed to r apidly detect the pathogen. A partial genomic library of F. oxysporum f. sp . canariensis isolate 95-913 was used to identify a DNA sequence diagnostic for a lineage containing all tested isolates of F. oxysporum f. sp. canari ensis. Two oligonucleotide primers were designed and used to amplify a 567- bp fragment with F. oxysporum f. sp, canariensis DNAs. DNA from 61 outgroup isolates did not amplify using these primers. Once the primers were shown to amplify a 0.567-kb fragment from DNA of all the F: oxysporum f. sp. cana riensis isolates tested, a rapid DNA extraction procedure was developed tha t led to the correct identification of 98% of the tested F. oxysporum f. sp . canariensis isolates.