Molecular detection and identification of the foliar nematode Aphelenchoides fragariae on Andrographis paniculata in Indonesia

A PCR-based diagnostic assay using species-specific primers was performed to molecularly detect and identify the foliar nematode Aphelenchoides fragariae, which had initially been morphologically identified on Andrographis paniculata (locally known as ‘bitter king’) in Indonesia. All samples of Aphelenchoides isolates assayed were positively identified as A. fragariae as all amplified a 169-bp PCR product from the ITS1 rDNA region. The phylogenetic tree of ITS1 rDNA supported the morphological identification of the samples of Indonesian A. fragariae as clustered with other A. fragariae species reported from other countries. This is the first report of molecular identification of A. fragariae on bitter king in Indonesia or elsewhere.