Identification of Volatiles That Are Used in Discrimination Between Plants Infested with Prey or Nonprey Herbivores by a Predatory Mite

Abstract

Carnivorous arthropods can use herbivore-induced plant volatiles to locate their herbivorous prey. In the field, carnivores are confronted with information from plants infested with herbivores that may differ in their suitability as prey. Discrimination by the predatory mite Phytoseiulus persimilis between volatiles from lima bean plants infested with the prey herbivore Tetranychus urticae, or plants infested with the nonprey caterpillar Spodoptera exigua, depends on spider mite density. In this article, we analyzed the chemical composition of the volatile blends from T. urticae-infested lima bean plants at different densities of spider mites, and from S. exigua-infested plants. Based on the behavioral preferences of P. persimilis and the volatile profiles, we selected compounds that potentially enable the mite to discriminate between T. urticae-induced and S. exigua-induced volatiles. Subsequently, we demonstrated in Y-tube olfactometer assays that the relatively large amounts of methyl salicylate and (3E, 7E)-4,8,12-trimethyl-1,3,7,11-tridecatetraene emitted by T. urticae-infested bean plants compared to S. exigua-infested plants enable the predators to discriminate. Our data show that specific compounds from complex herbivore-induced volatile blends can play an important role in the selective foraging behavior of natural enemies of herbivorous arthropods.

Induction of a leaf specific geranylgeranyl pyrophosphate synthase and emission of (E,E)-4,8,12-trimethyltrideca-1,3,7,11-tetraene in tomato are dependent on both jasmonic acid and salicylic acid signaling pathways

“…Spider mite-infested tomato plants emit signiWcantly more TMTT than uninfested tomato plants . The role of TMTT in the attraction of predatory mites has been investigated with lima bean (Phaseolus lunatus) as model system (De Boer et al 2004). Predatory mites prefer the odor source of lima bean infested with spider mites above that of lima bean infested with beet armyworm (Spodoptera exigua).…”

The products of a single maize sesquiterpene synthase form a volatile defense signal that attracts natural enemies of maize herbivores

“…Attempts to dissect the volatile signal emitted by herbivore-damaged leaves of lima bean (1) and maize (8), for instance, could not identify a specific compound responsible for enemy attraction, suggesting that mixtures constitute the active signal. However, the application of individual plant volatiles, such as methyl salicylate and the sesquiterpene alcohol nerolidol, in behavioral assays have been occasionally reported to attract parasitoids (9) and predatory mites (10)(11)(12).…”

Plant–plant–plant communications, mediated by (E)-β-ocimene emitted from transgenic tobacco plants, prime indirect defense responses of lima beans

“…Notably, (E)-DMNT and TMTT have also been reported to function as airborne cues that attract predatory mites (de Boer et al 2004;Kappers et al 2005), which may explain our previously reported findings that infested, second receiver plants that had been placed near infested VOCos-receiver plants were more attractive to P. persimilis in comparison to those that had been placed near the infested VOCwt-receiver plants (Muroi et al 2011). …”