The earlier the better? Impact of planting date and maturity group on Megacopta cribraria management in soybeans

Since its introduction in 2009, Megacopta cribraria (F.) has spread rapidly throughout the southeastern US, mainly feeding and reproducing on kudzu and soybeans. Megacopta cribraria has become a serious economic pest in soybeans, forcing growers to rely solely on insecticide applications to control this insect. The main objective of this study was to investigate if variation in planting date and maturity group of soybeans had an impact on management of M. cribraria populations. Experimental fields were located in NC and SC, and replicated in 2012 and 2013. Treatment consisted of three planting dates, four maturity groups, and insecticide treated vs. untreated (split-plot) at each location. Significantly more M. cribraria were found in early-planted soybeans. Generally, maturity group did not influence M. cribraria population densities. Yield was significantly reduced by the presence of M. cribraria when soybeans were planted in April and received no insecticide treatment. Although early-planted soybeans may avoid potential large abundance of stink bug and corn earworm, these fields may be more at risk for infestation by M. cribraria.