Proposal Objectives & Goal Statements:
• Objective 1: Assessing combined effects of Japanese beetle and soybean aphid on soybean
o Goal 1: Determine combined effects of Japanese beetle and soybean aphid on soybean yield and quality
o Goal 2: Determine effects of Japanese beetle feeding alone and in conjunction with soybean aphid on plant spectral reflectance
Proposal (15,000 characters):
The project proposed here aligns well with the mission statement of the MSR&PC Production Action Team and specifically addresses the following “Grower Assessed Priority Areas”:
1. “Soybean Farmers need integrated pest management strategies that deal with new or acute infestations of insect pests…” (Japanese is a new invasive insect affecting MN agriculture)
Background: The soybean aphid (Aphis glycines), continues to be the most damaging insect pest of soybean. However, the Japanese beetle (Popillia japonica), another invasive species from Asia, is spreading and causing increasing injury to soybean. Japanese beetle is an emerging crop pest concern across the region. These two pests now co-occur in soybean fields in southern Minnesota, but it remains unknown how their combined injury affects soybean. Without this knowledge, growers are unable to make fully informed manage decisions. Growers could be unnecessarily increasing insecticide inputs or incurring yield losses due to damaging infestations not being treated appropriately. Likewise, it is unclear how Japanese beetle feeding could affect efforts to use drone-based scouting for soybean aphid. The aim of this project is to improve the sustainability of soybean production by advancing management recommendations for combined infestations of soybean aphid and Japanese beetle.
Objective 1: Assessing combined effects of Japanese beetle and soybean aphid on soybean. (Koch, Cira, Behnken & Miller)
Justification:
This objective will improve management of and scouting for combined infestations of soybean aphid and Japanese beetle in soybean fields. The first component of this objective will quantify the effects of combined infestation of soybean aphid and Japanese beetle on soybean yield and quality. These results will inform management recommendations (treatment thresholds) to ensure these pests are being optimally managed. Thresholds exist for determining when to apply insecticides for either of these pests alone, but research-based recommendations are lacking for management of combined infestation by these pests. Research in other crops indicates combined attack by two or more different insect pests may result in additive (impact to the plant equal to sum of impacts from individual pests), synergistic (impact to the plant greater than sum of impacts from individual pests) or antagonistic (impact to the plant less than sum of impacts from individual pests) effects on the crop. Because the interactions between soybean and these two insects remain unknown, growers may be making incorrect decisions for management of these pests, such as: 1. applying insecticide when not necessary (wasted input costs) or not applying insecticide when it would have been necessary (lost yield due to unmitigated pest injury). Therefore, research is needed to characterize the combined effects of Japanese beetle and soybean aphid on soybean yield, which will provide a research-based foundation to improve management of these two pests.
The second objective will characterize the effects of soybean aphid and Japanese beetle feeding individually and combined on plant spectral reflectance to increase the accuracy of drone-based remote sensing for soybean insect pests. Previous work from the Koch lab has shown potential for use of drones to scout for soybean aphid. This new technology could reduce the time and effort needed to scout for aphids. However, the potential confounding impact of other stressors, such as Japanese beetle, on remotely sensed spectral data need to be understood