Changes of feeding behavior and salivary proteome of Brown Marmorated Stink Bug when exposed to insect‑induced plant defenses

The invasive Brown Marmorated Stink Bug (BMSB), Halyomorpha halys Stål, has dispersed widely throughout North America and Europe, negatively impacting agro-ecosystems and urban areas. This species is phytophagous and highly gregarious at all developmental stages. Therefore, it is important to determine how the congeners react to plant defenses induced by first infestation. Lipoxygenase activity was found to be enhanced in faba bean (Vicia faba L.) leaves by BMSB feeding or its salivary compounds. We analyzed BMSB feeding behavior by comparison with our previously published EPG waveform library for that pest, and identified some EPG variables associated with test probes, stylets pathway, and sustained ingestion. We demonstrated that, on elicited plants, BMSB probes were delayed, with sustained ingestion events being shorter. Moreover, significant changes in salivary gland proteins involved in plant allelochemical detoxification were detected when BMSB was exposed to plant defenses. Our results confirmed that this polyphagous invasive Heteroptera has the ability to detect plant defenses and to adapt its feeding strategies in consequence.