Cladosporium: the cause of ghost leaf spot of Taro in Thailand

Colocasia esculenta (Taro) is a high consuming root vegetable in Thailand. The ghost leafspot has been observed on C. esculenta in Chiang Mai province. The symptoms began as brown leaf spots on older leaves. The lesions were observed to be less evident on the opposite surface of the leaves. Pathogenicity assay was performed on detached, wounded leaves using the spore suspension. The disease symptoms appeared 10 days after the inoculation. The re-isolation of the fungi from the symptomatic tissues confirmed our isolate as the pathogen. The morphology shows the pathogen morphologically resembles Cladosporium. The phylogenetic placement of the pathogen was performed using concatenated internal transcribed spacers (ITS) Translation elongation factor 1-alpha (TEF-1α) and actin (ACT). The morphology and phylogeny revealed this fungus belongs to Cladosporium.