The partial characterization of Ilarviruses infecting Prunus species in Australia
Ilarviruses infect Prunus species with significant economic impact on commercial Prunus industries in Australia. Important Ilarvirus species of Prunus species in Australia are Apple mosaic virus (ApMV), Prunus necrotic ringspot virus (PNRSV) and Prune dwarf virus (PDV) and their diversity and incidence in Australia is not well understood. To understand their strain variation, 178 Prunus tree samples were tested using species-specific Ilarvirus RT-PCR tests targeting the coat protein gene of PNRSV, ApMV and PDV and genus-specific RT-PCR test that targets the RdRP gene of ilarviruses. Variation in the detection of ilarviruses between the species-specific and genus-specific RT-PCR tests indicated genetic variation of ilarviruses in the Prunus trees. Selected samples were inoculated on cucumber (Cucumis sativus) indicators and a variation in symptom expression and detection of ilarviruses using the species-specific and genus-specific RT-PCR tests was observed. The PCR products from the Prunus tree and cucumber indicators were sequenced and phylogenetic analysis of the coat protein and RdRP sequences showed clustering of cucumber Ilarvirus isolates away from the Prunus tree isolates suggesting that the cucumber indicators were selecting for specific sequence variants. Further sequence analysis indicated presence of genetic variation amongst Ilarvirus variants in Prunus tree and and the cucumber indicators were selecting for these sequence variants.
Kinoti, W., Plummer, K., Constable, F., Nancarrow, N. and Rodoni, B. (2016). The partial characterization of Ilarviruses infecting Prunus species in Australia. Acta Hortic. 1109, 243-248
Ilarvirus, Prunus, PNRSV, ApMV, PDV, RT-PCR, variation, diversity