Submitted to: Environmental Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/31/2016
Publication Date: 10/15/2016
Citation: Cornelius, M.L., Dieckhoff, C., Vinyard, B.T., Hoelmer, K.A. 2016. Parasitism and predation on sentinel egg masses of the brown marmorated stink bug (Hemiptera: Pentatomidae) in three vegetable crops: Importance of dissections for evaluating the impact of native parasitoids on an exotic pest. Environmental Entomology. 45(6):1536-1542.

Interpretive Summary: We conducted a survey to examine parasitism, predation and the species composition of native parasitoids attacking sentinel egg masses of the invasive pest, the brown marmorated stink bug, in bell pepper, squash, and tomato. The species composition of parasitoids was determined for parasitoids that successfully emerged from eggs, parasitoids that were identified from dissections, and parasitoids that were found guarding egg masses at the time of collection. The overall rate of nymphal emergence was 82.7% from laboratory-reared egg masses and 23.4% from sentinel egg masses due to a combination of predation, parasitism, and unknown causes. Overall, 12.4% of eggs were parasitized. Parasitoids emerged successfully from only 2.3% of eggs, but they were dissected from an additional 10.2% of eggs. This study demonstrates that the impact of native parasitoids on BMSB egg mortality is greatly underestimated based solely on parasitoid emergence rates alone. This study also provides valuable information that can help farmers and urban gardeners mitigate the damage caused to vegetable crops by the exotic invasive brown marmorated stink bug through the use of biological control agents.

Technical Abstract: We conducted a survey to examine parasitism, predation and the species composition of native parasitoids attacking sentinel egg masses of the invasive pest, the brown marmorated stink bug (BMSB), Halyomorpha halys (Stål), in bell pepper, squash, and tomato. A two-year survey was conducted for each crop. The species composition of parasitoids was determined for parasitoids that successfully emerged from eggs, parasitoids that were identified from dissections, and parasitoids that were found guarding egg masses at the time of collection. The overall rate of nymphal emergence was 82.7% from laboratory-reared egg masses and 23.4% from sentinel egg masses due to a combination of predation, parasitism, and unknown causes. Overall, 12.4% of eggs were parasitized. Parasitoids emerged successfully from only 2.3% of eggs, but they were dissected from an additional 10.2% of eggs. Telenomus podisi was the predominant species identified from emerged parasitoids (57.4%), dissected parasitoids (90.2%), and parasitoids guarding egg masses (77%).This study demonstrates that the impact of native parasitoids on BMSB egg mortality is greatly underestimated based solely on parasitoid emergence rates alone.