Temperature regimes and aphid density interactions differentially influence VOC emissions in Arabidopsis

Abstract

17The effects of volatile emissions from plants exposed to individual abiotic and biotic stresses are well 18 documented. However, the influence of multiple stresses on plant photosynthesis and defense responses, resulting in a 19 variety of volatile profiles has received little attention. In this study, we investigated how temperature regimes in the 20 presence and absence of the sucking insect Myzus persicae affected volatile organic compound emissions in 21Arabidopsis over three time periods (0-24 h, 24-48 h, and 48-72 h). Headspace solid-phase microextraction coupled 22 with gas chromatography-mass spectrometry was used to evaluate Arabidopsis volatile organic compounds. The results 23showed that under laboratory conditions, eight volatile classes [alcohols (mainly 2-ethyl-hexan-1-ol), ketone (6-methyl 24 hept-5-en-2-one), esters (mainly (Z)-3-hexenyl acetate), aldehydes (mainly phenylacetaldehyde), isothiocyanates 25(mainly 4-methylpentyl isothiocyanate), terpenes (mainly (E,E)-α-farnesene), nitrile (5-(methylthio) pentanenitrile), and 26 sulfide (dimethyl trisulfide)] were observed on plants exposed to stress combinations, whereas emissions of six volatile 27 classes were observed during temperature stress treatments alone (with the exception of nitriles and sulfides). Aphid

Myzus persicae Feeding on Water Stressed-Arabidopsis Affects the Emission Profile of Plant Volatile Organic Compounds

“…The production of GS-derived volatiles by A. thaliana has been shown to be induced by aphid infestations (Mewis et al, 2005;Van Poecke, 2007;Ma and Ma, 2012;Truong et al, 2014). Similarly, in the present study, GS hydrolysis products, such as 4-methylpentyl ITC and DMDS, were detected in the VOC emission profiles of both water-controlled and water-stressed Arabidopsis infested by M. persicae.…”

“…Seventy adults M. persicae were applied per plant according to Truong et al (2014). Additional water-controlled and water-stressed plants were left without aphid treatment as controls.…”

“…Similar to our recent study on the effect of temperature-herbivorous interactions on Arabidopsis volatile emissions (Truong et al, 2014), headspace solid phase microextraction (HS-SPME) using polydimethylsiloxane/divinylbenzene (PDMS/DVB) fibers (65 µm; Supelo, Bellefonte, PA, USA) was performed. Briefly, volatile collection from Arabidopsis exposed to different stress treatments was performed over three time periods, 0-24 h, 24-48 h, and 48-72 h, with HS-SPME samplings collected six hours before the end of each period.…”

“…Studies of aphid-fed Arabidopsis thaliana (L.) Heynh (A. thaliana) have shown that these the plant systemic acquired resistance (SAR) are induced as a pest avoidance mechanism via the salicylate (SA) signaling pathway to release VOCs (e.g., terpenoids and glucosinolate (GS) metabolites) (Vallad and Goodman, 2004;Van Poecke, 2007;De Vos and Jander, 2010;Louis et al, 2012). As a host plant of green peach aphids (Myzus persicae), variations in the emission profile of volatiles from Arabidopsis due to aphid feeding is well-documented (Mewis et al, 2005;Kim and Jander, 2007;Van Poecke, 2007;De Vos and Jander, 2009;Louis et al, 2012;Truong et al, 2014). In particular, Mewis et al (2005) have reported that the emission of indole GS from Arabidopsis plants increases with aphid M. persicae infestation.…”

Plants under dual attack : consequences for plant chemistry and parasitoid behavior

“…Variation in herbivore density is known to affect tritrophic interactions in the case of single herbivore attack (Dicke et al, 1988;Gols et al, 2003;Shiojiri et al, 2010;Girling et al, 2011), and also to affect induced plant volatile emissions, with the effects of density being either linear or nonlinear depending on the plant and insect species involved (Maeda & Takabayashi, 2001;Horiuchi et al, 2003;Shiojiri et al, 2010;Girling et al, 2011;Truong et al, 2014). For multiple attack scenarios, relatively little is known about the effects of herbivore density, although the effect of non-host herbivore density has been shown to trickle up to affect the third trophic level (Zhang et al, 2009).…”