Researchers identify new potential switchgrass virus

By Anna Austin | November 11, 2010

Diagnosing a virus is often the key to stopping it, but that is difficult when there is little or no prior information about the virus or the crop it’s attacking. This situation is particularly relevant to biomass energy crops, many of which have never been commercially produced in the U.S.

Recently, researchers at the University of Illinois identified a potential new insect-transmitted switchgrass virus that could reduce photosynthesis and biomass yields. Twenty to 30 percent of a switchgrass research field near the campus was infected with a virus, belonging to the genus Marafivirus, that is characterized by mosaic and yellow streaks on the switchgrass leaves. Members of this genus are notorious for causing severe yield losses in other crops, such as corn.

Although it is known that leafhoppers, which are minute plant-feeding insects, are responsible for transmitting the virus in corn fields, researchers are still working to identify the exact species that causes the virus in switchgrass, according to Bright Agindotan, research associate at the Energy Biosciences Institute in the Institute for Genomic Biology at the university.   

Typically, a virus must be characterized and diagnostic reagents must be developed before it can be correctly identified. However, because energy crops are new to North America, there is little information about which viruses will infect them. That is expected to change, as Agindotan has successfully developed a method that allows for the identification of a virus without prior knowledge, using sequence-independent amplification (SIA) to identify ribonucleic acid (RNA) viruses.

Currently, researchers can’t confirm whether the virus could affect other crops, but to test the identification method, virus-infected corn, soybean and wheat plants were analyzed, and all three test viruses were correctly identified. In the bioenergy crops, the method detected a new virus in switchgrass and a virus commonly found in corn in both miscanthus and switchgrass.

Researchers believe the method will be of interest to scientists who are interested in identifying and characterizing new viruses or new virus diseases of plants.

“Application of Sequence-Independent Amplification (SIA) for the Identification of RNA Viruses in Bioenergy Crops” was published in the Journal of Virological Methods in October.