Location: Foreign Disease-Weed Science ResearchTitle: Aphid vectors impose a major bottleneck on Soybean dwarf virus populations for horizontal transmission in soybean
|TIAN, BIN - Kansas State University|
|GILDOW, FREDERICK - Pennsylvania State University|
|DAMSTEEGT, VERNON - Former ARS Employee|
|SCHNEIDER, WILLIAM - Former ARS Employee|
Submitted to: Phytopathology Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/25/2019
Publication Date: 10/18/2019
Citation: Tian, B., Gildow, F.E., Stone, A.L., Sherman, D.J., Damsteegt, V.D., Schneider, W.L. 2019. Aphid vectors impose a major bottleneck on Soybean dwarf virus populations for horizontal transmission in soybean. Phytopathology Research. 1:29. https://doi.org/10.1186/s42483-019-0037-3.
Interpretive Summary: Soybean dwarf virus (SbDV) is a luteovirus that causes a stunting and yellowing disease in soybean. In Japan, soybean yield losses of up to 80% have been reported. In the U.S., SbDV has been reported in soybean in localized areas only. However, it is endemic in various clover species in the U.S. If SbDV could readily move from clover to soybean, the U.S could face a much larger soybean disease outbreak. The soybean aphid, Aphis glycines, was first detected in the U.S. in 2000 and is now prevalent in all soybean growing areas. Viral fitness depends on the interaction between the virus, the plant host, and the insect vector. This manuscript describes the interaction between SbDV and the soybean aphid. We demonstrate that as SbDV adapts to soybean, transmission by the soybean aphid decreases. This trade-off may serve to limit the spread of SbDV to and within soybean by the soybean aphid.
Technical Abstract: Many RNA viruses have genetically diverse populations in a single host. Important biological characteristics may be related to the levels of diversity, including adaptability, host specificity, and host range. Shifting the virus between hosts might result in a change in the levels of diversity associated with the new host. The level of genetic diversity for these viruses is related to host, vector and virus interactions; understanding these interactions may facilitate the prediction and prevention of emerging viral diseases. It is known that luteoviruses have a very specific interaction with aphid vectors. Previous studies suggested that there may be a trade-off effect between the viral adaptation and aphid transmission when Soybean dwarf virus (SbDV) was transmitted into new plant hosts by aphid vectors. In this study, virus titers in different aphid vectors and the levels of population diversity of SbDV in different plant hosts were examined during the course of transmission assays. The diversity of SbDV populations revealed biases for particular types of substitutions and regions of the genome that may accumulate more mutations among different hosts. The selection on SbDV in soybean was probably leading to loss of the virus-vector interaction. The most probable virus binding site is at the accessory salivary gland which is known for specific interactions between aphid and virus in many systems.