Location: Floral and Nursery Plants ResearchTitle: First report of Apple necrotic mosaic virus infecting apple trees in Korea Author
Submitted to: Journal of Plant Pathology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/18/2017
Publication Date: N/A
Citation: N/A Interpretive Summary: Virus and viroid disease cause losses in yield and quality in a wide range of horticultural crops, including ornamentals and fruit trees. A mosaic disease similar to that caused by Apple mosaic virus was observed in apple trees grown in Poncheon, Korea, but Apple mosaic virus was not detected by standard tests. The use of molecular methods to detect Apple necrotic mosaic virus, a recently discovered distinct virus causing similar symptoms in apple reported recently from China and Japan, confirmed the presence of this new virus in two apple trees in Korea. Knowledge of the presence of Apple necrotic mosaic virus in Korea will allow screening of apple propagation stocks for the presence of this new virus in order to minimize the spread of the virus and possible additional crop losses caused by Apple necrotic mosaic virus.
Technical Abstract: In September 2016, two apple trees (Malus domestica Borkh) cv. Shinano Sweet showing bright cream spot and mosaic patterns on leaves were observed in Pocheon, South Korea. Mosaic symptoms are common on leaves of apple trees infected with Apple mosaic virus (ApMV). Symptomatic leaves were tested by enzyme-linked immunosorbent assay (ELISA) and reverse transcription (RT)-PCR for ApMV, but this virus was not detected in either of the samples. Apple necrotic mosaic virus (ApNMV) is a recently described novel ilarvirus isolated from apple trees in Japan and China and correlated with a mosaic disease similar to that caused by Apple mosaic virus (ApMV). The presence of ApNMV was confirmed by RT-PCR with specific primer pairs ApNMV-CP+1 and ApNMV-CP-1. Expected PCR fragments of ca. 650bp were amplified and directly sequenced. BLASTn results showed 94% nucleotide sequence identity with the CP region of the previously published ApNMV (LC108995). The consensus sequence of Korean strain KO (LC276940) was deposited in GenBank. The ApNMV-positive samples were also infected with Apple chlorotic leaf spot virus (ACLSV), Apple stem grooving virus (ASGV) and Apple stem pitting virus (ASPV). To our knowledge, this is the first report of ApNMV infecting apple trees in Korea. Further research is needed to establish the relationship between ApNMV and ApMV causing mosaic disease on apple trees.