Evaluation of Dot-Immunobinding Assay and Rapid Immunofilter Paper Assay for　Detection of Cymbidium Mosaic Virus in Orchids

Dot-immunobinding assay (DIA) on nitrocellulose membranes and rapid immunofilter paper assay (RIPA) were examind for their usefulness in the detection of cymbidium mosaic virus (CyMV) in orchids. The minimum detection levels of CyMV by these methods were 100 ng/ml in purified preparations and at 10-4 dilution of extracts from infected leaves of orchids could be detected by these methods. Although DIA took 5 to 6 hours for the detection of the virus, it was reliable method for diagnosis of a large-number of samples. On the other hand, RIPA, which enabled detection of CyMV within a few minutes with sensitivity similar to that of DIA, will be suitable as a rapid and handy tool for virus disease diagnosis in orchids. Moreover, by RIPA, we could detect CyMV and odontoglossum ringspot virus (ORSV) simultaneously form doubly infected plant.

Dot-immunobinding assay （DIA）法とrapid immunofilter paper assay （RIPA）法の2種の血清学的診療法をcymbidium mosaic virus （CyMV）の検出に適用したところ、両方法とも少なくとも純化ウイルスで100ng/ml、罹病葉汁液では10-4希釈まで検出可能であった。DIA法では検出に5～6時間要したが、本法は多量の資料の診断に適していると思われた。一方、RIPA法では本ウイルスをDIA法と同程度の検出感度で数分以内で正確に検出できたことから、本法は今後のCyMVの簡易・迅速診断法として多種属のラン科植物に広く活用できると考えられた。さらにRIPA法ではCyMVとORSVに重複感染した植物から両ウイルスを同時に検出できた。