|Keough, Stacy - Indiana University-Purdue University|
|Danielson, Jonathan - Indiana University-Purdue University|
|Marshall, Jordan - Indiana University-Purdue University|
|Voegtlin, David - University Of Illinois|
|Srinivasan, Rajagopalbabu - University Of Georgia|
|Nachappa, Punya - Indiana University-Purdue University|
Submitted to: Environmental Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/22/2018
Publication Date: 3/1/2018
Citation: Keough, S., Danielson, J., Marshall, J.M., Lagos-Kutz, D.M., Voegtlin, D., Srinivasan, R., Nachappa, P. 2018. Factors affecting population dynamics of thrips vectors of soybean vein necrosis virus. Environmental Entomology. 47(3):734-740. doi: 10.1093/ee/nvy021.
DOI: https://doi.org/10.1093/ee/nvy021 Interpretive Summary: The sugarcane aphid, is an exotic species in the United States that was first reported in Florida in 1978 and in Louisiana in 2001. Its distribution has expanded to many south-eastern and central states, and has been a major concern for sorghum production in Texas and some surrounding states since 2013. In our study, based on the Midwest Suction Trap Network, we recorded the aphid at new locations in 2015, 2016, and 2017 with some catches as far north as northern Wisconsin. This species is a threat to sorghum and potential other cereal and energy crops of economic importance. This information is useful for researchers, extension agents, and producers that are interested in the sugarcane aphid and dispersal of aphids and insects in general across the crop production areas in the United States.
Technical Abstract: Thrips-infesting soybeans were considered of minor economic importance, but recent evidence of their ability to transmit a newly identified soybean virus, Soybean vein necrosis virus (SVNV), has raised their profile as pests. Season-long surveys were conducted using suction traps to determine the effects of temperature and precipitation on the spatiotemporal patterns of three vector species of SVNV, Neohydatothrips variabilis (Beach) (Thysanoptera: Thripidae) (soybean thrips), Frankliniella tritici (Fitch) (Thysanoptera: Thripidae) (eastern flower thrips), and Frankliniella fusca (Hinds) (Thysanoptera: Thripidae) (tobacco thrips) in soybean fields in Indiana in 2013 and 2014. In addition, soybean fields were surveyed for presence of SVNV in both years. We found that the magnitude and timing of thrips activity varied greatly for the three species. N. variabilis activity peaked in mid-August each year. The peak activity for F. tritici occurred between late-June, and a second peak in activity was observed in early-August, while F. fusca activity remained more or less the same with no peak. There was no gradient in thrips populations from southern to northern locations. This suggests that these insects are not migratory and may overwinter in soil or perennial noncrop host plants and other weed hosts in Indiana. The capture rates of N. variabilis and F. tritici were only related to temperature, and capture rates of F. fusca were not related to either variable. SVNV was first detected in mid-late August, which coincided with the peak of the primary vector, N. variabilis. The virus was not detected earlier in the season despite peaks in F. tritici activity. Our results may be used in weather-based models to predict both thrips dynamics as well as SVNV outbreaks.