Methyl salicylate as a signaling compound that contributes to forest ecosystem stability

Abstract

Key message This review for the first time gathers the current state of knowledge on the role of plant and microbial methyl salicylate (MeSA) signaling processes in forest ecosystems. It aims to establish a basis for the use of high-MeSA-emitting trees as a silvicultural tool aiming to enhance stability and resilience in managed temperate forests affected by climate change. Abstract Methyl salicylate (MeSA) is a volatile plant and microbial signaling compound involved in systemic acquired resistance (SAR) and defense against pests and microbial pathogens, and antagonists. MeSA emitted by plants is also believed to trigger SAR in neighboring plant individuals, thus contributing to the resilience of the entire plant community. In this review, we discuss volatile plant-to-plant communication processes with a special focus on MeSA and provide an overview about the occurrence of MeSA in fungi and other microbes. We summarize present findings on the role of MeSA in plants and particularly in birches (Betula spp.) and discuss the potential use of MeSA and MeSA-emitting plants in agriculture and forestry. MeSA levels in plant tissues are adjusted by methylation of salicylic acid to MeSA and the reverse process of demethylation. Some plant species possess constitutively high MeSA levels and thus are suitable for experiments of admixture of high MeSA plants, e.g., birches of the subgenera Betulenta and Acuminata in plant communities such as mixed forests. Furthermore, knowledge of candidate genes and the molecular pathways underlying high MeSA emission is expected to offer a basis for altering MeSA levels and/or the selection of high MeSA mutants.

Plant hormone cytokinin at the crossroads of stress priming and control of photosynthesis

“…The traditional plant defense response related to the hormones salicylic acid (SA), jasmonic acid (JA) and ethylene (ET) are interlinked in a complex network regulating plant immunity ( Conrath, 2006 ; Mishina and Zeier, 2007 ; Pieterse et al., 2009 ; Engelberth et al., 2011 ; Fragnière et al., 2011 ; Pieterse et al., 2014 ). These compounds and their volatile derivatives are well-documented as priming agents in many physiological processes ( Farmer and Ryan, 1990 ; Engelberth et al., 2011 ; Song and Ryu, 2018 ; Avramova, 2019 ; Zhao et al., 2020 ; Singewar et al., 2021 ). In last decades, the participation of CKs in biotic ( Choi et al., 2011 ; Cortleven et al., 2019 ) and abiotic ( Barciszewski et al., 2000 ; Wani et al., 2016 ) stress responses has also been demonstrated; however, less is known about the molecular aspects of CKs in priming.…”

Rapid Identification of Aphid Species by Headspace GC-MS and Discriminant Analysis

“…Both aphid species belong to the same family of Aphididae. S2 and (82)(83)(84)(85)(86)(87)(88)(89)(90)(91)(92)(93)(94)(95)(96) refer to the headspace compounds in Table 2.…”

Vaccinating plants

“…As mentioned above, MeSA is a key signaling molecule in the intra-organismal induction of SAR. However, as a volatile compound, it can also serve as an airborne inter-organismal signal that induces resistance in neighboring plants (Liu et al, 2018), thereby contributing to the local ecosystem stability (Singewar et al, 2021). An elegant proof for this activity of MeSA was recently presented by Ninkovic et al (2021), showing that exposure of barley plants to this volatile compound led to the production of systemic resistance factors.…”