Submitted to: Journal of Virological Methods
Publication Type: Peer reviewed journal
Publication Acceptance Date: 1/9/2003
Publication Date: 5/25/2003
Citation: Redinbaugh, M.G. 2003. Transmission of maize streak virus by vascular puncture inoculation with plasmid dna genome monomers. Journal of Virological Methods. 109:95-98. Interpretive Summary: Technically simple methods for transmission of viruses without the use of insect vectors are needed to facilitate research on plant viruses and the diseases they cause. Several years ago, a scientist in the Corn and Soybean Research Unit developed vascular puncture inoculation (VPI) to transmit viruses to maize without insects. VPI involves using a jeweler's engraving tool to push very fine pins through a virus-containing drop into the scutellum of germinating kernels. More recently, we demonstrated that RNA and DNA that encode maize viruses can be transmitted by VPI. In this report, a simplified approach for transmitting Maize streak virus from cloned DNA was developed. Use of this approach will save researchers several steps and several days in preparing clones of the virus for inoculation into maize. This will facilitate analysis of multiple clones in research to identify virus gene function.
Technical Abstract: The infectivity of cloned maize streak virus (MSV) monomers was tested using vascular puncture inoculation (VPI). Plasmid DNA containing either a single copy of the MSV genome (MSV monomer) or a head-to-tail dimer of the MSV genome (MSV dimer) cloned into the BamHI site of pUC19 were used as inoculum. VPI of kernels with the MSV dimer incited infection in 38+/-12% of inoculated plants. In contrast, VPI with the MSV monomer produced no infection. However, if the MSV monomer was digested with BamHI prior to VPI, 16+/-3% of plants became infected. Extracts of systemically infected leaves from plants inoculated with MSV dimer and the BamHI-digested MSV monomer were equally infectious suggesting the inocula produced similar systemic infections.