Native North American vs. Asian parasitoid natural enemies of invasive BMSB

Authors: ABRAM, PAUL - Agriculture And Agri-Food Canada; Hoelmer, Kim

Submitted to: International Symposium on Biological Control of Arthropods
Publication Type: Proceedings
Publication Acceptance Date: 6/19/2017
Publication Date: 9/11/2017
Citation: Abram, P.K., Hoelmer, K.A. 2017. Native North American vs. Asian parasitoid natural enemies of invasive BMSB. International Symposium on Biological Control of Arthropods. p 248. http://www.isbca-2017.org/index.php?cat=PROccedings.

Interpretive Summary:

Technical Abstract: The invasion of brown marmorated stink bug (BMSB), Halyomorpha halys Stål (Hemiptera: Pentatomidae), in North America and Europe spurred efforts to characterize indigenous natural enemies attacking this pest in the native range and in invaded regions. At the time of the North American invasion, available literature on Asian natural enemies of BMSB was sparse. As interest in Asian natural enemies has grown for a possible biological control solution, recent surveys have compiled additional records from the native Asian range, particularly for egg parasitoids. Several species of Trissolcus egg parasitoids were found in most surveys. Recent taxonomic studies on Trissolcus of the Nearctic and Palearctic will help make this task easier. The most widespread and important natural enemy in Asia appears to be the egg parasitoid Trissolcus japonicus (Ashmead) (Hymenoptera: Scelionidae) (also in literature as T. halyomorphae Yang ), with high rates of parasitism reported in several studies. Besides BMSB, Trissolcus T. japonicus also attacks several other species of Asian pentatomids. Survey datasets of native natural enemies attacking BMSB in North America and Europe comprise a variety of sampling methods, habitats, and geographic areas. To date, the majority of research has focused on predators and parasitoids of H. halys eggs, using both sentinel and wild egg masses to characterize composition and impact of enemy communities. Parasitism and predation rates are typically <10%, although they may be substantial in certain habitats, such as ornamental plant nurseries. As yet, there is no evidence that resident North American parasitoids are adapting to BMSB. This contrasts with the impact of egg parasitism in the native Asian range, which is considerably greater, suggesting the need for classical biocontrol to help manage this pest. Studies of natural enemies attacking H. halys nymphs and adults are less common to date but researchers are starting to focus more attention on resident predators and pathogens. U.S. researchers received an unexpected surprise when specimens of T. japonicus were identified in field survey samples collected near Washington D.C. during the 2014 field season. This species was under study in quarantine laboratories but had not been released. Subsequent surveys have shown that the adventive population has established and is spreading, and two additional adventive populations have been discovered in northeastern states and northwestern states. This will afford the opportunity to observe the impact of this parasitoid on BMSB and non-target species in an invaded region. Given the extensive crop damage that has occurred following the establishment of BMSB in North America, there is considerable concern that BMSB will continue to spread to other parts of the world. Further spread in North America and Europe is possible, and substantial parts of Africa, South America and Australasia are at risk. A more complete knowledge and understanding of the known BMSB natural enemies will help researchers to develop biological control strategies for newly-invaded areas.