Euphydryas

It has been found a relationship between the concentration and the kind of iridoids in some plants rich on iridoids with the oviposition and larvae cycle of some species of the Lepidopterae, Nymphalidae and Chrysomelidae families, like Euphydryas [9], Junonia [10, 11], Melitaea [12], Longitarsus [13] genus. 

Moths and butterflies that sequester iridoid compounds are unpalatable to birds that might be potential predators. Adults of Euphydryas phaeton that fed on Chelone glabra (Scrophulariaceae) during larval development are emetic to birds that eat a piece of the butterfly (Rimpler, 1991). 

Gardner, D. R. and F. R. Stermitz, Host plant utilization and iridoid glycoside sequestration by Euphydryas anicia (Lepidop-tera Nymphalidae), J. Chem. Ecol., 14, 2147-2168 (1988). 

Stermitz, F. R., D. R. Gardner, F. J. Odendaal, and P. R. Ehrlich, Euphydryas anicia (Lepidoptera Nymphalidae) utilization of iridoid monoterpenes from Castilleja and Besseya (Scro-phulariaceae) host plants, J. Chem. Ecol., 12, 1459-1468 (1986b). 

Stermitz, F. R., G. N. Belofsky, D. Ng, and M. C. Singer, Quinolizidine alkaloids obtained by Pedicularis semibarbata (Scrophulariaceae) from Lupinus fulcratus (Leguminosae) fail to influence the specialist herbivore Euphydryas editha (Lepi-doptera) oviposition. J. Chem. Ecol., 15, 2521-2530 (1989). 

Dahl et al. demonstrated that the release of methanol dramatically increases and can be substantially greater than the release of -2-hexenal when Manduca sexta larvae attacks Nicotiana attenuata plants [54]. Similar results were also obtained during monitoring VOCs induced by Euphydryas aurinia caterpillars feeding on Succisa pratemis leaves [55]. The emission of ethanol, acetaldehyde, acetic acid, ethyl acetate, 2-butanone, 23,-butanedione, and acetone from Arabidopsis roots has been identified by both PTR-MS and GC-MS [56]. The rapid release of 1,8-cineole and a monoterpene was demonstrated after compatible interactions of Pseudomonas syringae DC3000 and Diuraphis noxia with roots. But mechanical injuries to roots did not release any wound-induced VOCs, and the VOCs released were basically the same for the infected and noninfected roots. 

Penuelas, J., Filella, 1., Stefanescu, C., Llusia, J. (2005) Caterpillars of Euphydryas aurinia (Lepidoptera Nymphalidae) feeding on Succisapratensis leaves induce large foliar emissions of methanol. The New Phytologist, 167,851-857. 

The volatile emissions induced by caterpillars larvae (Euphydryas aurinia) feeding on Devils-bit Scabious (Succisa pratensis) are shown in the following example... 

Singer, M. C. (1982) Quantification of host preference by manipulation of oviposition behavior in the butterfly Euphydryas editha. Oecologia, 52, 224-9. 

The first study was by Penuelas et al. [203]. This revealed that Euphydryas aurinia caterpillars feeding on Succisa pratensis leaves induced emissions of large amounts of methanol and other VOCs (including monoterpenes, sesquiterpenes and lipoxygenase-derived volatile compounds (e.g. (Z)-3hexenal and (Z)-3-hexenyl acetate)). VOC release was monitored immediately after leaf attack (within the first hour) and after 1 day of continuous herbivorous feeding. Some of the VOCs observed at the start of the... 

---