Olfactory Response of the Predatory Bug Orius laevigatus (Hemiptera:Anthocoridae) to the Aggregation Pheromone of Its Prey, Frankliniella occidentalis (Thysanoptera: Thripidae)

Abstract

Herbivore natural enemies base their foraging decision on information cues from different trophic levels but mainly from plant odors. However, the second trophic level (i.e., the herbivorous prey) may also provide reliable infochemical cues for their natural enemies. We have evaluated the role of the aggregation pheromone from Frankliniella occidentalis (Pergande) as a potential kairomone for its natural enemy, the predatory bug Orius laevigatus (Fieber). For this purpose, we have analyzed the response of O. laevigatus to (R)-lavandulyl acetate and neryl (S)-2-methylbutanoate, the two major components of the thrips aggregation pheromone. These compounds have been offered to O. laevigatus adult females and nymphs of the predatory bugs both in separate and as specific (1:1 or 1:2.3) blends, in experiments involving a dual choice Y-tube olfactometer. None of the compounds attracted adults or nymphs when they were individually supplied. Conversely, they were significantly attracted to both adults and nymphs when offered as a blend. A 1:2.3 (R)-lavandulyl acetate:neryl (S)-2-methylbutanoate blend was attractive to both nymphs and adults, while a 1:1 blend elicited response only in nymphs. These results suggest that specific blends of these compounds from the aggregation pheromone may be used as an attractant to O. laevigatus. The results of this work highlight the importance of studying olfactory responses of natural enemies for a better understanding of their foraging behavior. Potential uses of these results in future studies are discussed.

Role of Thrips Omnivory and Their Aggregation Pheromone on Multitrophic Interactions Between Sweet Pepper Plants, Aphids, and Hoverflies

“…1794) (Diptera: Syrphidae) in the absence of aphids (Almohamad et al, 2009). In contrast, the predatory bug O. laevigatus, a natural enemy of F. occidentalis, responded positively to the aggregation pheromone of its prey (Vaello et al, 2017). Thus, the aggregation pheromone RLA:NMB seems to act both as an attractant for a thrips predator such as O. laevigatus and as repellent for S. rueppellii.…”

“…In order to prepare the odor source, tested compounds were individually diluted (1:1, v/v) in paraffin oil (Sigma-Aldrich, USA). The ratio used in this experiment was selected according to previous results testing the attraction of the natural enemy O. laevigatus to F. occidentalis aggregation pheromone (Vaello et al, 2017). Parafilm oil (2 µl) (used as control) and 1RLA:2.3NMB blend (2 µl) were applied on a piece of filter paper (1 × 1 cm) that was placed on the second expanded leaf of the sweet pepper plant.…”

“…Moreover, we expected that the aggregation pheromone of F. occidentalis [(R)-lavandulyl acetate: neryl (S)-2methylbutanoate], could be used by S. rueppellii to discriminate between plants with or without thrips. This hypothesis is based on our previous results showing that the thrips aggregation pheromone was attractive to a thrips natural enemy, the predatory bug Orius laevigatus (Fieber 1860) (Hemiptera: Anthocoridae) (Vaello et al, 2017).…”

Foraging behavior responses of Orius insidiosus to thrips cues

“…It indicates that the switch in foraging behavior is led by cues associated by thrips cues, not by satiation. Previous research into anthocorid semiochemistry involving sex pheromones and herbivore‐induced plant volatiles has provided a foundation for potential manipulation opportunities towards the optimization of attraction and biological control of F. occidentalis by Orius species (MacDonald et al, 2003; Gebreziher & Nakamuta, 2016; Vaello et al, 2017). However, there remains little previous research into non‐volatile chemoreception of non‐pheromonal contact cues produced by thrips and the resulting behavioral effects on predators such as O. insidiosus , which may aid in assessment of patch productivity, presenting manipulation opportunities (Vaello et al, 2017).…”

Enhancing pest management in sweet pepper by the exploitation of zoophytophagy

“…Such evidence has also been obtained for N. tenuis, M. pygmaeus and O. laevigatus, who responded to the odour emitted from prey infested plants (Moayeri et al, 2006;Ingegno et al, 2011;Lins et al, 2014;De Backer et al, 2015;Rim et al, 2015Rim et al, , 2017Vaello et al, 2017). Recently, the activity (feeding behaviours and oviposition) of zoophytophagous predators was observed to induce HIPVs (De Puysseleyr et al, 2011;Pérez-Hedo et al, 2015a, 2015bPappas et al, 2015Pappas et al, , 2016Naselli et al, 2016 …”