First Report of Soybean Mosaic Virus on Soybean in North Dakota

Authors: NELSON, BERLIN - North Dakota State University; Domier, Leslie

Submitted to: Plant Disease
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/5/2009
Publication Date: 7/1/2009
Citation: Nelson, B. and Domier, L.L. 2009. First Report of Soybean mosaic Virus on Soybean in North Dakota. Plant Disease. 93(7):760.

Interpretive Summary: Soybeans are grown on more than 3,500,000 acres in North Dakota and are the most important oilseed crop in the state. Virus infections in commercial soybean fields have not been reported previously from North Dakota. In July and August of 2007, 64 soybean fields in Cass, Richland and Sargent counties in southeastern North Dakota were surveyed for Soybean mosaic virus (SMV). SMV was detected in 19 of the 64 soybean fields sampled with immunological reagents that detected SMV proteins. To confirm the presence of SMV, 12 SMV-positive samples also were tested for the presence of SMV genomic RNA. Eight of the 12 samples were shown to also contain SMV genomic RNA, confirming the presence of SMV in the samples. This is the first report of SMV infecting soybean in North Dakota. The incidence of SMV infection in commercial soybean fields has been very low for several years. Since they were first detected in the United States in 2000, soybean aphids, which can transmit SMV, have become perennial pests in soybean fields in north central states. The detection of SMV in multiple commercial soybean fields in this region may indicate an increasing incidence of the virus and a potential for it to cause crop losses. These finding will be of interest to soybean breeders because few commercial soybean lines are resistant to SMV infection.

Technical Abstract: Soybean, Glycine max (L) Merr., is grown on 1,420,000 ha in North Dakota and is the most important oilseed crop in the state. Viruses in soybean have not previously been reported from North Dakota (1). In July and August of 2007, 64 soybean fields in Cass, Richland and Sargent counties in southeastern North Dakota were surveyed for Soybean mosaic virus (SMV). These counties have a high concentration of soybean hectares, a long history of soybean production and soybean aphid infestations have been observed. Fields were sampled on a grid pattern across the area with at least 5 miles between fields. A transect of about 60 m through each field was made and 20 leaves were collected at random. Sap was extracted in phosphate buffer and stored at -80° C until tested first with double antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA) using positive controls and reagents and protocol from Agdia (Elkhart, IN). Using DAS-ELISA, SMV was detected in 19 of the 64 soybean fields sampled. To confirm the presence of SMV, twelve samples that were positive for SMV by DAS-ELISA also were tested using reverse transcription-polymerase chain reaction (RT-PCR). RNA was extracted from sap using Qiagen RNeasy Plant Mini Kit (Germantown, MD), reverse transcribed, and amplified with SuperScrip III Platinum SYBR Green One-Step qRT-PCR kit (Invitrogen, Carlsbad, CA), and SMV-specific primers (5'-TTCAGCACAATGGGTGAGGATG-3' and 5'-AATTCTGTGTGGCTTGATGTTGC-3'). Eight of the 12 ELISA-positive samples were positive for SMV by RT-PCR, confirming the presence of SMV in the samples. To our knowledge this is the first report of SMV infecting soybean in North Dakota.