Location: Invasive Species and Pollinator HealthTitle: Adventive Gryon aetherium Talamas (Hymenoptera, Scelionidae) associated with eggs of Bagrada hilaris (Burmeister) (Hemiptera, Pentatomidae) in the USA
|TALAMAS, ELIJAH - Florida Department Of Agriculture And Consumer Services|
Submitted to: Journal of Hymenoptera Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/22/2021
Publication Date: 12/23/2021
Citation: Hogg, B.N., Hougardy, E.H., Talamas, E. 2021. Adventive Gryon aetherium Talamas (Hymenoptera, Scelionidae) associated with eggs of Bagrada hilaris (Burmeister) (Hemiptera, Pentatomidae) in the USA. Journal of Hymenoptera Research. 87:481-492. https://doi.org/10.3897/jhr.87.73778.
Interpretive Summary: Bagrada bug is a stinkbug that has become a major pest of cole crops (i.e., cabbage, broccoli, cauliflower, kale, etc.) in California since its arrival in 2008. Parasitic wasps that attack the bug’s eggs may help control it. Unlike other stinkbugs bagrada bug lays its eggs in the soil, where the eggs may be protected from natural enemies. In this study we examined whether parasitic wasps attack bagrada bug eggs at a highly infested site in northern California. Two parasitic wasp species were found attacking eggs that were placed in the foliage of infested plants, but only one of these species was found attacking eggs in the soil. The latter wasp species was previously collected in Pakistan and was being tested as a possible biological control agent for bagrada bug. Mating experiments showed that crossing Pakistani and Californian wasps yielded viable female offspring, confirming that they are the same species. This report marks the first known record of this parasitic wasp in the USA, and further work will be conducted to examine its effectiveness in controlling bagrada bug.
Technical Abstract: Bagrada bug, Bagrada hilaris Burmeister (Hemiptera, Pentatomidae), has become a major pest of cole crops (Brassicaceae) in California since its arrival in 2008. In this study we documented parasitism of B. hilaris eggs at a highly infested site in northern California by deploying sentinel B. hilaris eggs and collecting naturally-laid B. hilaris eggs in the soil. Two parasitoids, Gryon aetherium Talamas (Scelionidae) and Ooencyrtus lucidus Triapitsyn & Ganjisaffar (Encyrtidae) emerged from sentinel eggs, but only G. aetherium was documented attacking eggs in the soil. Gryon aetherium is currently being assessed as a classical biological control agent for B. hilaris in California, and mating experiments showed that crosses between G. aetherium from Pakistan and California yielded viable female offspring. This report marks the first known record of G. aetherium in the USA, and further work should be conducted to assess the potential of this parasitoid for biological control of B. hilaris.