Effect of Brown Marmorated Stink Bug (Halyomorpha halys Stål.) Infestation on the Phenolic Response and Quality of Olive Fruits (Olea europaea L.)

Abstract

Olives ripen in the late autumn and represent a good source of nutrients that Halyomorpha halys uses to prepare for diapause. This is the first study to investigate the impact of H. halys infestation on the phenolic response and olive fruit quality in the pierced tissue of damaged fruits and in the non-pierced part of damaged fruits of ‘Istrska belica’ and ‘Pendolino’ cultivars. Both total phenolic content and antioxidant capacity contents significantly increased in the infested fruits of the cultivar ‘Istrska belica’. Total phenolic content in the pierced tissue of damaged fruits increased by 10.7%, while the content of AC in the non-pierced tissue of damaged fruits increased by 7.11% and in the pierced tissue of damaged fruits by 6.1% compared to control. A total of 44 individual phenolic compounds were identified, 21 of them increased in at least one cultivar after infestation. Huge increases in phenolic content were observed in both cultivars, particularly for flavones, secoiridoids, anthocyanins, and flavonols in the pierced tissue of damaged fruits. The most responsive individual phenolic compound in both cultivars was oleuropein. Its content in the pierced tissue of damaged fruits increased by 44.7% in the cultivar ‘Pendolino’ and for 82.6% in the cultivar ‘Istrska belica’.