Interaction between Halyomorpha halys Stål and its host plant: induced defense and feeding behavior

Halyomorpha halys Stål (Heteroptera, Pentatomidae), the Brown Marmorated Stink Bug (BMSB), is native to Eastern Asia, where it feeds on a large diversity of host plants. BMSB has been accidentally introduced in Switzerland, Europe, where first observations occurred in 2007. It is probable that the pest will have colonized a large part of Europe within the next decades. It is therefore crucial to better understand its biology to develop efficient control strategies. Phytophagous Pentatomidae use different feeding strategies according to the plant tissue. On seeds, they apply a cell rupturing strategy, while on leaves and stems, they secrete a salivary sheath to facilitate the penetration of the stylets through the cells. Regarding their feeding strategies, they are more likely to induce mainly the jasmonic acid pathway as a plant defensive response. Yet, there is a lack of knowledge concerning the behavioral and physiological response of an insect exposed to an elicited plant.
Therefore, we aimed to enlighten the interactions between BMSB and one of its host plant, focusing on: (1) the validation of the hypothesis that jasmonic acid pathway is induced by this insect feeding; (2) whether other individuals are subsequently able to detect that response and adapt their feeding strategies or salivary compounds. Our results highlighted a local and systemic defensive response in leaves after an attack by BMSB or after its saliva injection. Furthermore, we proposed a first description of electrical penetration graph waveforms for that pest. Then we showed some differences in feeding behavior parameters and in salivary compounds according to the plant treatment. We replaced these results in the context of such a polyphagous invasive species and its ability to overcome the plant defense to successfully settle and feed.