Crosstalk among Jasmonate, Salicylate and Ethylene Signaling Pathways in Plant Disease and Immune Responses

Abstract

Phytohormone crosstalk is crucial for plant defenses against pathogens and insects in which salicylic acid (SA), jasmonic acid (JA), and ethylene (ET) play key roles. These low molecular mass signals critically trigger and modulate plant resistance against biotrophic as well as necrotrophic pathogens through a complex signaling network that even involves participation of other hormones. Crosstalk among SA, JA and ET is mediated by different molecular players, considered as integral part of these crosscommunicating signal transduction pathways. Recent progress has revealed that the positive versus negative interactions among those pathways ultimately enable a plant to fine-tune its defense against specific aggressors. On the other hand, pathogens have evolved strategies to manipulate the signaling network to their favour in order to intensify virulence on host plant. Here we review recent advances and current knowledge on the role of classical primary defense hormones SA, JA and ET as well as their synergistic and antagonistic interaction in plant disease and immune responses. Crosstalk with other hormones such as abscisic acid, auxin, brassinosteroids, cytokinins and melatonin is also discussed mainly in plant disease resistance. In addition to our keen focus on hormonal crosstalk, this review also highlights potential implication of positive and negative regulatory interactions for developing an efficient disease management strategy through manipulation of hormone signaling in plant.

Resistance against Ralstonia solanacearum in tomato depends on the methionine cycle and the γ‐aminobutyric acid metabolic pathway

“…Moreover, in plants, the hormone ethylene is synthesized from SAM in two enzymatic steps, and SAM is an intermediate in the MTC. Ethylene acts as a primary signal participating in the pathogen response (Lorenzo et al ., ; Yang et al ., ). In the current study, regulation of the MTC pathway could, to some extent, directly lead to alteration of the ethylene level.…”

Mycorrhiza and Common Mycorrhizal Network Regulate the Production of Signal Substances in Trifoliate Orange (Poncirus trifoliata)

“…CaM as the second messenger always responds to various stimulations and also regulates massive cellular functions (Berridge et al, 2000). The SA and JA-dependence signaling pathways play a crucial role in plant defense reactions (Yang et al, 2015), and the subject has gained more attention in the recent past. Allene oxide synthase (AOS), 13-lipoxygenase (LOX), and allene oxide cyclase (AOC) are key enzymes in JA biosynthesis pathway, the relative genes expression level which significantly influences JA concentration (Kombrink, 2012).…”

Comparative transcriptional profiling of Gracilariopsis lemaneiformis in response to salicylic acid- and methyl jasmonate-mediated heat resistance

“…Previous studies have demonstrated that SA- and JA-dependent defense signaling pathways are antagonistic or synergistic with each other [27,28]. Salicylic acid 2- O -β-D-glucose (SAG) shows synergistic activity in the JA-related defense response in terms of the MDA, PPO and PAL activities in pea seedlings [29].…”