Orientation behavior of predaceous ground beetle species in response to volatile emissions identified from yellow starthistle damaged by an invasive slug

Abstract

We investigated indirect defense in the yellow starthistle (Centaurea solstitialis)-grey garden slug (Deroceras reticulatum)-ground beetle (Pterostichus melanarius and Scaphinotus interruptus) system. In this host plant/ herbivore/predator system, the ground beetles are the primary predator of D. reticulatum, the dominant herbivore of the highly invasive weed, C. solstitialis. The aim of our study was to examine the behavioral responses of two species of ground beetle to olfactory stimuli emitted from yellow starthistle damaged by D. reticulatum. The beetle P. melanarius showed a significant preference for the odor of damaged yellow starthistle relative to the odor of intact plants, while S. interruptus did not. Volatiles from D. reticulatum-damaged yellow starthistle were collected and identified as trans-b-farnesene, germacrene D, bicyclogermacrene, and 1,5,9-trimethyl-1,5,9-cyclododecatriene. No quantitative relationship was observed between beetle plant choice or decision time and the level of herbivory. Similarly, there was no relationship between volatile compound relative abundance and level of herbivory, suggesting that our range of leaf damage produces either undetectable semiochemicals or no variation in volatile emission.

Seed Detection and Discrimination by Ground Beetles (Coleoptera: Carabidae) Are Associated with Olfactory Cues

“…Although we know that olfactory cues can be significant in carabid detection of invertebrate prey [21, 34, 35], relatively little is known about behavioural responses of carabids to potential olfactory cues emitted by weed seeds. Better understanding differential responses of beetles to seed odours has implications for understanding weed seed predation under field conditions.…”

In‐field volatile analysis employing a hand‐held portable GC‐MS: emission profiles differentiate damaged and undamaged yellow starthistle flower heads

“…Germacrene D was the highest overall volatile emitted when its average relative abundance is summed across all treatments. It has also been observed in high abundance in other studies of yellow starthistle (Beck et al , ; Senatore et al , ; Kilic, ; Smith and Beck, ; Oster et al , ). Germacrene D is a common plant volatile with noted semiochemical characteristics (El‐Sayed, ).…”

“…In situ flower heads of yellow starthistle were used as the target organ. Leaf volatile emissions of yellow starthistle have been well studied (Beck et al ., ; Smith and Beck, ; Oster et al ., ) with the resultant volatile profiles used to elucidate the chemical ecology of the plant and its associated biocontrol agents. Additionally, volatiles of the essential oil have been reported for aerial portions and flower heads of yellow starthistle (Senatore et al ., ; Kilic, ).…”

“…Examples include: seed‐ or ovary‐feeding weevils ( Bangasternus orientalis , Eustenopus villosus and Larinus curtus ) (Pitcairn et al , ; Birdsall and Markin, ) and flies ( Chaetorellia succinea , Urophora sirunaseva ) (Balciunas and Villegas, ), the rosette‐feeding weevil Ceraptapion basicorne (Smith, ), the phloem‐feeding lace bug Tingis grisea (Paolini et al, ), the rust, Puccinia jaceae var. solstitialis (Woods et al , ) and the leaf‐ and seedling‐feeding slug Deroceras reticulatum (Oster et al ., ). Several of these studies have highlighted plant volatiles as attracting the herbivores or predators of herbivores.…”

Duration of emission of volatile organic compounds from mechanically damaged plant leaves

“…Piesik et al (2010) observed that a 24-h exposure to leaf feeding beetles stimulated higher production of VOCs than mechanical damage of several grasses, and that both types of damage resulted in much more emission than undamaged plants. Similarly, a 24-h exposure of yellow starthistle plant leaves to slugs resulted in the detection of four sesquiterpenes from the damaged plant, whereas no volatiles were detected in the nondamaged plant (Oster et al, 2014).…”