Combining irradiation and biological control against brown marmorated stink bug: Are sterile eggs a suitable substrate for the egg parasitoid Trissolcus japonicus

Authors: ROSELLI, GERADO - University Of Trento, Italy; ANFORA, GIANFRANCO - University Of Trento, Italy; SASSO, RAFFAELE - Enea Casaccia Research Center; ZAPPONI, LIVIA - National Research Council - Italy; MUSCMECI, SERGIO - Enea Casaccia Research Center; SEMMI, ALESSIA - Enea Casaccia Research Center; SUCKLING, DAVID MAXWELL - Agresearch; HOELMER, KIM - US Department Of Agriculture (USDA); IORATTI, CLAUDIO - Fondazione Edmund Mach; CRISTOFARO, MASSIMO - Biotechnology And Biological Control Agency

Submitted to: Insects
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/18/2023
Publication Date: 7/22/2023
Citation: Roselli, G., Anfora, G., Sasso, R., Zapponi, L., Muscmeci, S., Semmi, A., Suckling, D., Hoelmer, K., Ioratti, C., Cristofaro, M. 2023. Combining irradiation and biological control against brown marmorated stink bug: Are sterile eggs a suitable substrate for the egg parasitoid Trissolcus japonicus. Insects. (14)654. https://doi.org/10.3390/insects14070654.
DOI: https://doi.org/10.3390/insects14070654

Interpretive Summary: Brown marmorated stink bug, an invasive species native to south-eastern Asia, is now widely distributed worldwide. Management of this pest with insecticides is not very effective because of development of resistance and the high mobility of the pest. Classical biological control with co-evolved egg parasitoids is an option for management. The detection and collection of the egg parasitoid species is often conducted by exposing egg-masses of the stink bug pest in the field for a few days as sentinels, which can then be parasitized by the egg parasitoids. In newly invaded areas, limiting factors for using sentinel eggs include the short window of time they are a suitable substrate for the oviposition by parasitoids and the risk of the unintentional release of additional pests from unparasitized eggs. A potential alternative is to use sterile sentinel eggs of the pest species. This study determined that irradiated sterile sentinel eggs were suitable for the oviposition and the larval development of the egg parasitoid Trissolcus japonicus.

Technical Abstract: The brown marmorated stink bug (BMSB), Halyomorpha halys, a phytophagous invasive pest native to southeastern Asia, is now distributed worldwide, and is one of the most damaging insect pests in North America and in Europe. In agriculture, the predominant approach to managing BMSB is based on the use of pyrethroid and neonicotinoid insecticides. However, the biology of BMSB and its ability to develop mechanisms of resistance to pesticides has led to the development of less-toxic and more effective strategies of control. In an area-wide approach, the use of a classical biological control program in combination with other least-toxic strategies has been given prominent consideration. Following exploratory surveys in the native range, attention has focused on Trissolcus japonicus, a scelionid egg parasitoid wasp that is able to oviposit and complete its larval development in eggs of H. halys. A common method for detecting egg parasitoids in the native range involves the placement of so-called ‘sentinel’ egg masses of the pest in the environment for a short period, which are then returned to the laboratory to determine if any are parasitized. Outside of the area of origin, the use of fertile sentinel eggs can be problematic; an alternative is to use sterile sentinel eggs to record the presence of indigenous egg parasitoids or to detect the dispersal of T. japonicus released in a new region to control BMSB. This study evaluated the performance of three types of sterile sentinel eggs as a suitable substrate for the oviposition and larval development of the egg parasitoid T. japonicus in a context of combining classical biological control with a Sterile Insect Technique (SIT) approach.