Plutella xylostella(L.) infestations at varyingtemperatures induce the emission of specificvolatile blends byArabidopsis thaliana(L.) Heynh

摘要

The effect of combined abiotic and biotic factors on plant volatile organic compound (VOC) emissions is poorlyunderstood. This study evaluated the VOC emissions produced byArabidopsis thaliana(L.) Col-0 subjected to 3temperature regimes (17, 22, and27C) in the presence and absence ofPlutella xylostellalarvae over 2 time intervals (0–4 and 4–8 h), in comparison to control plants. The analyses of VOCs emitted byArabidopsisplants were made byheadspace solid phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS). Itwas found that certain volatile groups (e.g., alcohols, ketones, aldehydes, and terpenes) are induced by both singlefactors (temperature or larval infestation) and combined factors (temperature and larvae interactions), whereas othervolatile groups (e.g., isothiocyanates [ITCs] and nitrile) were specific to the experimental conditions. ITCs (mainly 4-methylpentyl isothiocyanate) were emitted from plants subjected to larval infestation at 17 and 27C after the 2 timeintervals. The proportions of sulfides (mainly dimethyl disulfide) and 4-(methylthio) butanenitrile were significantlyhigher on herbivore-infested plants at 22C compared to the other treatments. Overall, ourfindings indicate thatchanges in all experimental conditions caused significant changes to the VOC emissions ofArabidopsisplants.Therefore, the interaction between temperature and larval feeding may represent an important factor determining thevariability of volatile emissions by plants subjected to multiple simultaneous factors.