Molecular phylogeny and genetic diversity of Fusarium oxysporum from various hosts in Malaysia.

Fusarium oxysporum is a cosmopolitan fungus, consisting of both pathogenic and non-pathogenic members and known to be the causative agent of several diseases on various host plants. In Malaysia, most studies have focused on pathogenic F. oxysporum isolates because of their implications for agricultural production, but less attention has been given to non-pathogenic isolates. The aim of this study was to determine the phylogenetic relationship, genetic diversity, pathogenicity and host range of F. oxysporum in Malaysia. A total of 133 isolates of F. oxysporum were isolated from symptomatic plants of Abelmoschus esculentus, Solanum melongena, Solanum tuberosum, Cucumis sativus, Solanum lycopersicum, Cucumis melo, Musa paradisiaca var. awak, Hymenocallis littoralis, Asparagus officinalis, and Sansevieria trifasciata and non-agricultural soils in Malaysia. Comparison of nucleotide sequences of translation elongation factor 1-alpha (tef1-α) and mitochondrial small subunit (mtSSU) showed that the isolates were 98-100% similar to F. oxysporum from GenBank, thus, confirming the fungal identity. Besides, Malaysian isolates of F. oxysporum exhibited polyphyletic evolutionary origin, wide host range, and genetically diverse by grouping into 20 VCGs and 17 IGS haplotypes. This finding is beneficial for the purpose of quarantine, monitoring and disease management in the agricultural settings in Malaysia.