Towards a sustainable pest management of the invasive bug Halyomorpha halys in Trentino province, Italy

Abstract: Some invasive insects are agricultural pests, like the brown marmorated stinky bug (BMSB), an extremely phytophagous pentatomids. The lack of efficient low-impact control strategies makes this insect extremely dangerous for agricultural crops. In Italy, the first established populations of BMSB were found in 2012. In 2016 the insect appeared in Trentino, an intensive apple growing district. In this Thesis, a mixed method study was conducted to explore vibrational communication of BMSB as well as to analyse the stakeholder’s perception about the pest in Trentino. The vibrational communication of BMSB was investigated by using a laser vibrometer, playback signals. a custom-made cardstock and wooden arenas. Results from the behavioural experiments with vibration showed that signal characteristics, such as frequency and temporal pattern, can trigger or inhibit male search. Natural and edited female vibrational signals were broadcasted on different settings. Using natural female signal, almost 50% of the adult males tested actively searched for the vibrational source, with 70% reaching it within few minutes after release. This opens the possibility to develop new trapping devices for monitoring and mass trapping BMSB. Stakeholders’ perceptions were collected through semi-structured interviews. Interview transcripts were analysed using thematic analysis (TA). Respondents had similar views on the possible different control strategies: whereas insect nets and insecticides were considered not feasible solutions for the area, biological control by the exotic parasitic wasp Trissolcus japonicus was considered as the most promising solution. However, according to the analysis conducted, the national department for agriculture did not give the permission to investigate the biological control efficacy and the possible unwanted effect on the local ecosystem by T. japonicus in Italy. The lack of this permission was identified by the stakeholders as a main institutional slowdown towards the development of sustainable BMSB control in Trentino.