The Viruses in Gladiolus hybridus cultivated in Korea 1. Bean Yellow Mosaic Virus and Clover Yellow Vein Virus

한국산 글라디올러스에 발생하는 바이러스

Gladioli (Gladiolus hybridus) showing flower colour breaking, leaf mosaics, necrotic fleck, and dwarfing or lack of visible symptoms were collected from gladioli growing areas in Taegu and Kyungpook province, Korea. The two viruses isolated from the naturally infected gladioli were identified as ban yellow mosaic virus (BYMV) and clover yellow vein virus (CIYVV) by their host range, immunosorbent electron microscopy (ISEM), enzyme-linked immunosorbent assay (ELISA), direct tissue blotting immunoassay (DTBIA) and intracellural symptoms. In ultrathin sections of BYMV and CIYVV infected tissues, laminated aggregate-type inclusions, cytopalsmic bodies and nuclear inclusions as well as filamentous virus particles were observed in the cytoplasm of parenchyma cells. By DTBIA and ISEM, BYMV was detected in all tested gladiolus plants showing severe or mild mosaic symptoms, whereas CIYVV were mainly detected from those of mild mosaic symptoms. BYMV is the most prevalent in commercial gladioli and present major production problems. Detection sensitivity of BYMV and CIYVV in crude sap of infected gladiolus leaves by ISEM was about twice compared with ELISA. In a comparison of ELISA, ISEM, DTBIA, BYMV was detected in same degree by DTBIA in samples where sap extracts were positive in both ELISA and ISEM. DTBIA provides a specific, rapid, and simple tool for large-scale diagnosis of BYMV.