Elimination of Bean yellow mosaic virus through thermotherapy combined with meristem-tip culture in gladiolus corms

Bean yellow mosaic virus (BYMV, Potyvirus, Potyviridae) causes serious disease in Gladiolus spp. In this work, the possibility of obtaining BYMV free plant material from virus infected gladiolus corms was studied. Thermotherapy, meristem-tip culture and combination of both techniques on infected corms/meristem-tip explants (0.5–1 mm in length) resulted in BYMV elimination up to 15.38, 78.04 and 86.66%, respectively, as determined by double antibody sandwich-enzyme-linked immunosorbent assay (DAS-ELISA) and reverse transcription-polymerase chain reaction (IC-RT-PCR). Individual virus-free shoots readily rooted in vitro and were transferred to corm formation medium. The results showed that thermotherapy promotes the survival rate of explants during meristem-tip culture steps (except regeneration step) and also plantlet acclimatization. Statistical analysis showed that the BYMV elimination in gladiolus corms was significantly (P ? 0.01) affected by thermotherapy treatment of infected corms. Thermotherapy combined with meristem culture can greatly improve BYMV elimination efficiency from infected gladiolus corms, resulting in the production of BYMV free gladiolus plants.