Location: Vegetable Crops ResearchTitle: First report of soybean vein necrosis disease caused by soybean vein necrosis-associated virus in Wisconsin and Iowa Author
Submitted to: Plant Disease
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/26/2012
Publication Date: 5/20/2013
Citation: Smith, D.L., Fritz, C., Watson, Q., Willis, D.K., German, T.L., Phibbs, A., Mueller, D., Dittman, J.D., Saalau-Rojas, E., Whitham, S.A. 2013. First report of soybean vein necrosis disease caused by soybean vein necrosis-associated virus in Wisconsin and Iowa. Plant Disease. 97(5):693. Interpretive Summary: This report describes first identification of Soybean vein necrosis-associated virus in soybean fields Wisconsin and Iowa. The discovery of this disease in these states demonstrates the spread of this important soybean virus. At present, we assume the thrips insect vector that is wide spread in soybean growing areas transmits the virus. This information is important to soybean growers in Wisconsin and Iowa and will aid in the control of this new viral disease.
Technical Abstract: Several viral diseases of soybean (Glycine max) have been previously identified in the north-central U.S. soybean production area, which includes Wisconsin and Iowa (Hartman et al., 1999). In September 2012, soybean plants with symptoms similar to those reported for soybean vein necrosis disease (SVND) caused by Soybean vein necrosis-associated virus (SVNaV) (Zhou et al., 2011) were observed in fields across Wisconsin and Iowa. Symptoms included leaf-vein and leaf chlorosis, followed by necrosis of the leaf veins and eventually necrosis of the entire leaf. Six samples with symptoms indicative of SVNaV were collected from research plots located at the West Madison Agricultural Research Station located in Madison, WI. An additional three samples were collected from three locations in central Iowa. PCRs of two of the six Wisconsin samples and two Iowa samples were distinctly positive. The other five samples had weak or no positive amplification products. BLASTn (Altshul et al., 1990) alignments of the 915 bp consensus sequence revealed 98% and >99% identity of the Wisconsin and Iowa samples, respectively, with the ‘S’ segment of the SVNaV ‘TN’ isolate (GenBank Accession No. GU722319.1). Independent samples from the leaf tissue used above, were subjected to serological tests for SVNaV using antigen coated-indirect enzyme-linked immunosorbent assay. These tests confirmed the presence of SVNaV in eight symptomatic soybean leaflets collected in Wisconsin and Iowa.