Resistance to Cucumber mosaic virus in Gladiolus plants transformed with either a defective replicase or coat protein subgroup II gene from Cucumber mosaic virus.

Transgenic Gladiolus plants that contain either Cucumber mosaic virus (CMV) subgroup I coat protein, CMV subgroup II coat protein, CMV replicase, a combination of the CMV subgroups I and II coat proteins, or a combination of the CMV subgroup II coat protein and replicase genes were developed. These plants were multiplied in vitro and challenged with purified CMV isolated from Gladiolus using a hand-held gene gun. Three out of 19 independently transformed plants expressing the replicase gene under control of the duplicated CaMV 35S promoter were found to be resistant to CMV subgroup I.

Preparation of immunogens and production of antibodies.

The quality of reagents greatly affects the interpretation of serological tests. Methods used in conventional viral purification and molecular cloning and expression of target viral proteins to obtain antigens for immunization are presented. Immunization of rabbits, mice and chickens and isolation of immunoglobulin from immunized animals also are described.

Development of enzyme linked, tissue blot and dot blot immunoassays for plant virus detection.

Immunoassays are among the most powerful and useful techniques for analysis of biological materials. There are numerous variations in which immunoassays can be performed. Coupled with enzyme, using chromogenic substrates, the enzyme immunoassay technique is used to trace the target antigen in tissues.

Identification of Common Epitopes on a Conserved Region of NSs Proteins Among Tospoviruses of Watermelon silver mottle virus Serogroup.

ABSTRACT The NSs protein of Watermelon silver mottle virus (WSMoV) was expressed by a Zucchini yellow mosaic virus (ZYMV) vector in squash. The expressed NSs protein with a histidine tag and an additional NIa protease cleavage sequence was isolated by Ni(2+)-NTA resins as a free-form protein and further eluted after sodium dodecyl sulfate-polyacrylamide gel electrophoresis for production of rabbit antiserum and mouse monoclonal antibodies (MAbs). The rabbit antiserum strongly reacted with the NSs crude antigen of WSMoV and weakly reacted with that of a high-temperature-recovered gloxinia isolate (HT-1) of Capsicum chlorosis virus (CaCV), but not with that of Calla lily chlorotic spot virus (CCSV).

Serological Comparison and Molecular Characterization for Verification of Calla lily chlorotic spot virus as a New Tospovirus Species Belonging to Watermelon silver mottle virus Serogroup.

ABSTRACT Calla lily chlorotic spot virus (CCSV) isolated from central Taiwan was recently identified as a tospovirus serologically but distantly related to Watermelon silver mottle virus (WSMoV). To clarify the serological relationship between the two viruses, rabbit polyclonal antibody (PAb) to CCSV and mouse monoclonal antibodies (MAbs) to WSMoV NP or CCSV NP were produced in this investigation, using purified nucleocapsid protein (NP) as immunogens. The PAb to CCSV NP reacted stronger with the homologous antigen than with the heterologous antigen, with much lower A(405) readings in indirect enzyme-linked immunosorbent assay (ELISA) and low-intensity banding in immunoblotting.

Purification and serological analyses of tospoviral nucleocapsid proteins expressed by Zucchini yellow mosaic virus vector in squash.

A plant viral vector engineered from an in vivo infectious clone of Zucchini yellow mosaic virus (ZYMV) was used to express the nucleocapsid proteins (NPs) of tospoviruses in planta. The open reading frames (ORFs) of NPs of different serogroups of tospoviruses, including Tomato spotted wilt virus, Impatiens necrotic spot virus, Watermelon silver mottle virus, Peanut bud necrosis virus, and Watermelon bud necrosis virus (WBNV), were in frame inserted in between the P1 and HC-Pro genes of the ZYMV vector. Six histidine residues and an NIa protease cleavage site were added at the C-terminal region of the inserts to facilitate purification and process of free form of the expressed NPs, respectively.

Biolistic inoculation of gladiolus with cucumber mosaic cucumovirus.

A new method of inoculation of gladiolus with cucumber mosaic virus (CMV) was developed using the Bio-Rad Helios Gene Gun System. This method circumvents the traditional use of aphids to transmit CMV, a virus that is mechanically transmissible to many plant species but only with difficulty to gladiolus. Cartridges containing virus-coated gold microcarriers were prepared and the virus shot into Nicotianabenthamiana leaves and gladiolus corms and cormels.

Multiple virus infections in the honey bee and genome divergence of honey bee viruses.

Using uniplex RT-PCR we screened honey bee colonies for the presence of several bee viruses, including black queen cell virus (BQCV), deformed wing virus (DWV), Kashmir bee virus (KBV), and sacbrood virus (SBV), and described the detection of mixed virus infections in bees from these colonies. We report for the first time that individual bees can harbor four viruses simultaneously. We also developed a multiplex RT-PCR assay for the simultaneous detection of multiple bee viruses.