1st Place: D3079: Evaluating the impact of at-plant termination of a cereal rye cover crop with different corn planting dates on arthropod activity

Greater cover crop biomass production is expected to create a favorable microhabitat for beneficial arthropods. Cover crop termination guidelines are based on the cash crop planting date; therefore, delaying cash crop planting could result in greater cover crop biomass accumulation. However, cash crop planting delays and greater cover crop biomass accumulation have been shown to decrease the cash crop yield but haven’t accounted for the impact on arthropod activity. As a result, a two-year field study was conducted in eastern Nebraska to determine the impact of early and late corn planting dates with at-plant cover crop terminations on pest potential, beneficial arthropod activity, and agronomic parameters. Pitfall traps and corn injury assessments were used to measure arthropod and pest activity following each corn planting date during the early stages of corn development. A total of 11,054 and 43,078 arthropods were collected in 2020 and 2021, respectively. The results showed that there was no impact of the corn planting dates with at plant cover crop termination on arthropods. However, a cereal rye cover crop supported greater Araneae activity while its potential prey varied when compared to the no-cover treatment. Significant yield penalties occurred in our study when cover crop was used regardless of the corn planting dates. As pest pressure was not significant in any year, future research using different cover crop species should challenge the system with the addition of pests to be able to evaluate the trade-offs between possible cash crop yield reductions and potential biological control of pests.