Volatile-mediated plant–plant interactions: volatile organic compounds as modulators of receiver plant defence, growth, and reproduction

Abstract

It is firmly established that plants respond to biotic and abiotic stimuli by emitting volatile organic compounds (VOCs). These VOCs provide information on the physiological status of the emitter plant and are available for detection by the whole community. In the context of plant-plant interactions, research has focused mostly on defence-related responses of receiver plants. However, responses may span hormone signalling, both primary and secondary metabolism and ultimately affect plant fitness. Here we present a synthesis of plant-plant interactions focusing on the effects of VOC exposure on receiver plants. An overview of the important chemical cues, uptake and conversion of VOCs and the adsorption of VOCs to plant surfaces is presented. This is followed by review of the substantial VOC-induced changes to receiver plants affecting both primary and secondary metabolism and influencing plant growth and reproduction. Further research should consider whole plant responses for effective evaluation of mechanisms and fitness consequences of receiver plant exposure to VOCs.

Volatile-mediated between-plant communication in Scots pine and the effects of elevated ozone

“…A key observation in the present study was reduced herbivore-damage to Scots pine saplings that had been exposed to HIPVs, which is indicative of a gain in resistance. The underlying mechanism for this ecological effect is probably related to induced or primed defence responses [ 15 , 23 , 60 ]. VOCs are an important component of pine defence; they are toxic to bark beetles at high vapour concentrations, which has been shown to inhibit their feeding activity [ 61 , 62 ].…”

“…In addition to the production of defensive VOCs, a greater photosynthesis rate is expected to provide more resources for other C-based defensive chemicals, physical barriers and compensatory growth [ 4 , 60 , 63 ]. A physical structure related to the defensive chemistry of Scots pine is the RD, tube-like structures formed by secretory ECs that produce and exude terpenoid resin into the lumen [ 64 ].…”

Priming seeds for the future: Plant immune memory and application in crop protection

“…To prepare for the incoming pathogens, primed plants usually undergo metabolic changes in the biosynthesis of primary and secondary metabolites (Frost et al, 2008;War et al, 2011;Brosset and Blande, 2022). It was recently demonstrated that BABA treatment induced resistance to Botrytis cinerea and affected the contents of soluble sugar and phenylpropanoid metabolites in grape berries (Li et al, 2021a).…”

Effect of Drought and Methyl Jasmonate Treatment on Primary and Secondary Isoprenoid Metabolites Derived from the MEP Pathway in the White Spruce Picea glauca

“…Monoterpene emission stimulated by MeJA treatment was strongly attenuated by simultaneous drought stress at both sampling times. Reduction in monoterpene emission should decrease the ability of P. glauca to defend itself with volatiles either as direct or indirect defenses or to communicate with volatiles as internal signals as in angiosperm [ 55 , 56 ] to alert other parts of the tree to herbivore attack. This might reflect a reduced priority for anti-herbivore defense responses under an abiotic stress like drought.…”