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Duponchelia fovealis (Lepidoptera: Crambidae) was introduced in Brazil not long ago and causes severe yield losses to strawberry plantations. This situation demands the development of sustainable pest management strategies. Podisus nigrispinus (Hemiptera: Pentatomidae) is a Neotropical generalist predator that has potential to be used in biological control programs against D. fovealis. Herbivore-induced plant volatiles (HIPVs) are of great interest due to their potential uses in pest management programs, particularly for improving biological control. In this way, this study aims at measuring P. nigrispinus response to volatiles induced by D. fovealis-damaged strawberry plants of two cultivars, namely San Andreas and Albion. For this purpose, headspace volatiles emitted by strawberry plants were chemically characterized and behavioral assays of P. nigrispinus nymphs were performed using a Y-tube olfactometer. The two strawberry cultivars, Albion and San Andreas, emitted higher amounts of terpenoids after being exposed to herbivory by D. fovealis. Several compounds were only detected in the headspace of D. fovealis-damaged plants. In spite of some qualitative and quantitative differences, the genotype did not affect the volatile emissions. Podisus nigrispinus showed preference for herbivory-damaged Albion and San Andreas plants in comparison to undamaged plants. However, P. nigrispinus did not prefer herbivore-damaged plants of any cultivar in particular. The results indicate that HIPVs mediate tritrophic signaling in this model system.

Green mate, Ilex paraguariensis (Aquifoliaceae), is native to South America and its range includes the south of Brazil. Hedypathes betulinus (Coleoptera: Cerambycidae) is considered the most important insect pest of green mate, causing severe damage to plants and significant economic losses. In previous work, laboratory assays were performed to document the mating sequence of this species and the male long-range sex pheromone was identified. Previous reports of the mating sequence suggested that males recognize females only after antennal contact and consequently the existence of a contact sex pheromone. To test the hypothesis that mate-recognition in H. betulinus is mediated by a contact sex pheromone, this study analyzed male and female body extracts by GC-MS. Extracts were fractionated to separate the compounds by polarity, producing hexane, cyclohexene and ether fractions. Active fractions were identified with laboratory bioassays. Bioassays were performed by introducing female cadavers to live males and male copulation response scored (± ). In assays using solvent washed female cadavers, males did not recognize female cadavers, but attempted copulation with female cadavers with the extract re-applied. Cumulatively, these results suggest that a contact sex pheromone on the cuticle of females mediates mate recognition. Laboratory bioassays and analysis of the female solvent extracts produced by fractionation, individually and in binary and ternary combinations, suggests that the more polar compounds present in the ether fraction are crucial to mate recognition in this species.