|Kamenova, Ivanka - USHRL, ARS, USDA|
Submitted to: Plant Disease
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: August 22, 2003
Publication Date: January 1, 2004
Citation: Kamenova, I., Adkins, S. 2004. Comparison of Detection Methods for a Novel Tobamovirus Isolated From Florida Hibiscus. Plant Disease. 88:34-40. Interpretive Summary: Hibiscus (Hibiscus rosa-sinensis) is a landscape plant in the southern U.S. and a popular indoor/outdoor potted plant in the northern U.S. We recently isolated a putative tobamovirus from hibiscus in Florida landscape plantings. An initial survey for the distribution of this virus in landscape plants in Florida has shown a high level of incidence. Hibiscus and many of its relatives are vegetatively propagated. This important horticultural practice, however, is also a very effective method for plant infection and virus spread. A key element of disease management for such crops is indexing of stock plants to eliminate virus-infected plants prior to propagation. Thus, we tested and compared several methods for detection of this virus with the aim of selecting a procedure suitable for indexing stock plants. The rapidity, ease and sensitivity of these methods for the diagnosis of infected plants makes them amenable for routine testing to index stock plants as a general management plan to decrease the propagation of virus-infected hibiscus plants.
Technical Abstract: A novel tobamovirus was recently isolated from hibiscus in Florida. Serological and molecular methods including enzyme-linked immunosorbent assay (ELISA), dot blot immunoassay (DBIA), tissue blot immunoassay (TBIA) and immunocapture-reverse transcription-polymerase chain reaction (IC-RT-PCR) were compared to evaluate their usefulness for diagnosis of this virus. Each method was tested with partially purified virus preparations and tissue samples from infected hibiscus plants. Indirect ELISA was more sensitive than double antibody sandwich (DAS)-ELISA with all samples tested. End-point dilutions of partially purified virus preparations from indirect and DAS-ELISA were 4 ng/ml and 31 ng/ml, respectively. DBIA was less sensitive than either ELISA method. The virus was also reliably detected by TBIA from leaves and bark of hibiscus plants. The most sensitive method was IC-RT-PCR, which could detect as little as 500 pg/ml of virus in partially purified preparations and was 16- and 32-fold more sensitive than DAS-ELISA with hibiscus bark and leaf extracts, respectively. Over six hundred hibiscus samples were tested by various combinations of these methods to validate their usefulness.