We investigated the behavioral attractive responses of a lepidopteran larva parasite, Exorista japonica to 10 synthetic herbivore-induced plant volatiles (HIPVs). These synthetic HIPVs have been revealed the attractive effect on several parasites. For each of the HIPVs, we asked the following two questions : (1) Which volatiles show the attractiveness to this parasitoid, (2) Whether the attractant directly or indirectly affects the host settlement and parasitism of the parasitoid. To experimentally address these questions, we performed 2 and 4 choice indoor cage tests. E. japonica adults were significantly attracted to benzaldehyde and (Z)-3-hexen-1-ol showing higher settlement and parasitic rates on Spodoptera litura of treatments. Compared to the untreated plots, the average parasitism of E. japonica on S. litura larvae in the benzaldehyde treatments increased by approximately 20%.

The western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), is an important pest of horticultural and agricultural crops worldwide. The repeated use of chemical insecticides resulted in the development of insecticide resistance. We evaluated response of F. occidentalis to three synthetic herbivore-induced plant volatiles (HIPVs), methyl salicylate, methyl anthranilate, and nonanal known as attractants of thrips’ natural enemy, in Y-tube olfactometer. Mated fed adult females of F. occidentalis showed lowest response rate to methyl salicylate than methyl anthranilate, and nonanal. These results show that methyl salicylate may act as repellent to F. occidentalis, and can be used as a component of push-pull strategies for the management of F. occidentalis.

Orius spp. (Heteroptera: Anthocoridae) prey on small arthropods such as aphids, thrips, whitefly, and mites both in greenhouse and field. Use of chemical attractants to natural enemies can improve the efficacy of biological control through push-pull strategy. We compared attractiveness of three synthetic herbivore-induced plant volatiles (HIPVs), i.e., nonanal, methyl anthranilate, and methyl salicylate for thrips natural enemies, O. laevigatus (Fieber) and O. minutus (L.), in Y-tube olfactometer. Mated unfed adult females of O. laevigatus showed higher choice rate to methyl anthranilate or methyl salicylate than nonanal. Orius minutus showed higher choice rate to methyl anthranilate than methyl salicylate or nonanal. These results suggest that, among the three HIPVs, methyl anthranilate can be used for the attractant of both O. laevigatus and O. minutus.