Jasmonic Acid and Ethylene Signaling Pathways Regulate Glucosinolate Levels in Plants During Rhizobacteria-Induced Systemic Resistance Against a Leaf-Chewing Herbivore

Root inoculation of Arabidopsis thaliana ecotype Columbia with Pseudomonas fluorescens CHA0r partially protected leaves from the oomycete Peronospora parasitica. The molecular determinants of Pseudomonas fluorescens CHA0r for this induced systemic resistance (ISR) were investigated, using mutants derived from strain CHA0: CHA400 (pyoverdine deficient), CHA805 (exoprotease deficient), CHA77 (HCN deficient), CHA660 (pyoluteorin deficient), CHA631 (2,4-diacetylphloroglucinol [DAPG] deficient), and CHA89 (HCN, DAPG- and pyoluteorin deficient). Only mutations interfering with DAPG production led to a significant decrease in ISR to Peronospora parasitica. Thus, DAPG production in Pseudomonas fluorescens is required for the induction of ISR to Peronospora parasitica. DAPG is known for its antibiotic activity; however, our data indicate that one action of DAPG could be due to an effect on the physiology of the plant. DAPG at 10 to 100 μM applied to roots of Arabidopsis mimicked the ISR effect. CHA0r-mediated ISR was also tested in various Arabidopsis mutants and transgenic plants: NahG (transgenic line degrading salicylic acid [SA]), sid2-1 (nonproducing SA), npr1-1 (non-expressing NPR1 protein), jar1-1 (insensitive to jasmonic acid and methyl jasmonic acid), ein2-1 (insensitive to ethylene), etr1-1 (insensitive to ethylene), eir1-1 (insensitive to ethylene in roots), and pad2-1 (phytoalexin deficient). Only jar1-1, eir1-1, and npr1-1 mutants were unable to undergo ISR. Sensitivity to jasmonic acid and functional NPR1 and EIR1 proteins were required for full expression of CHA0r-mediated ISR. The requirements for ISR observed in this study in Peronospora parasitica induced by Pseudomonas fluorescens CHA0r only partially overlap with those published so far for Peronospora parasitica, indicating a great degree of flexibility in the molecular processes leading to ISR.

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Involvement of jasmonic acid, ethylene and salicylic acid signaling pathways behind the systemic resistance induced by Trichoderma longibrachiatum H9 in cucumber

BMC Genomics ◽

10.1186/s12864-019-5513-8 ◽

2019 ◽

Vol 20 (1) ◽

Cited By ~ 18

Author(s):

Min Yuan ◽

Yuanyuan Huang ◽

Weina Ge ◽

Zhenhua Jia ◽

Shuishan Song ◽

...

Keyword(s):

Salicylic Acid ◽

Jasmonic Acid ◽

Signaling Pathways ◽

Systemic Resistance ◽

Trichoderma Longibrachiatum ◽

Salicylic Acid Signaling

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Validamycin A Induces Broad-Spectrum Resistance Involving Salicylic Acid and Jasmonic Acid/Ethylene Signaling Pathways

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi-08-20-0211-r ◽

2020 ◽

Vol 33 (12) ◽

pp. 1424-1437

Author(s):

Chuanhong Bian ◽

Yabing Duan ◽

Jueyu Wang ◽

Qian Xiu ◽

Jianxin Wang ◽

...

Keyword(s):

Salicylic Acid ◽

Jasmonic Acid ◽

Plant Defense ◽

Signaling Pathways ◽

Broad Spectrum ◽

Defense Responses ◽

Systemic Resistance ◽

Signal Pathways ◽

Plant Defense Responses ◽

Validamycin A

Validamycin A (VMA) is an aminoglycoside antibiotic used to control rice sheath blight. Although it has been reported that VMA can induce the plant defense responses, the mechanism remains poorly understood. Here, we found that reactive oxygen species (ROS) bursts and callose deposition in Arabidopsis thaliana, rice (Oryza sativa L.), and wheat (Triticum aestivum L.) were induced by VMA and were most intense with 10 μg of VMA per milliliter at 24 h. Moreover, we showed that VMA induced resistance against Pseudomonas syringae, Botrytis cinerea, and Fusarium graminearum in Arabidopsis leaves, indicating that VMA induces broad-spectrum disease resistance in both dicots and monocots. In addition, VMA-mediated resistance against P. syringae was not induced in NahG transgenic plants, was partially decreased in npr1 mutants, and VMA-mediated resistance to B. cinerea was not induced in npr1, jar1, and ein2 mutants. These results strongly indicated that VMA triggers plant defense responses to both biotrophic and necrotrophic pathogens involved in salicylic acid (SA) and jasmonic acid/ethylene (JA/ET) signaling pathways and is dependent on NPR1. In addition, transcriptome analysis further revealed that VMA regulated the expression of genes involved in SA, JA/ET, abscisic acid (ABA), and auxin signal pathways. Taken together, VMA induces systemic resistance involving in SA and JA/ET signaling pathways and also exerts a positive influence on ABA and auxin signaling pathways. Our study highlights the creative application of VMA in triggering plant defense responses against plant pathogens, providing a valuable insight into applying VMA to enhance plant resistance and reduce the use of chemical pesticides. [Formula: see text] Copyright © 2020 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license .

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Involvement of Jasmonic Acid/Ethylene Signaling Pathway in the Systemic Resistance Induced in Cucumber by Trichoderma asperellum T203

Phytopathology ◽

10.1094/phyto-95-0076 ◽

2005 ◽

Vol 95 (1) ◽

pp. 76-84 ◽

Cited By ~ 256

Author(s):

Michal Shoresh ◽

Iris Yedidia ◽

Ilan Chet

Keyword(s):

Jasmonic Acid ◽

Pseudomonas Syringae ◽

Defense Mechanisms ◽

Plant Pathogens ◽

Polymerase Chain Reaction Analysis ◽

Systemic Resistance ◽

Signal Molecules ◽

Ethylene Signaling ◽

Trichoderma Spp ◽

Leaf Pathogen

Trichoderma spp. are effective biocontrol agents for a number of soilborne plant pathogens, and some are also known for their ability to enhance plant growth. It was recently suggested that Trichoderma also affects induced systemic resistance (ISR) mechanism in plants. Analysis of signal molecules involved in defense mechanisms and application of specific inhibitors indicated the involvement of jasmonic acid and ethylene in the protective effect conferred by Trichoderma spp. against the leaf pathogen Pseudomonas syringae pv. lachrymans. Moreover, examination of local and systemic gene expression by real-time reverse transcription-polymerase chain reaction analysis revealed that T. asperellum (T203) modulates the expression of genes involved in the jasmonate/ethylene signaling pathways of ISR (Lox1, Pal1, ETR1, and CTR1) in cucumber plants. We further showed that a subsequent challenge of Trichoderma-preinoculated plants with the leaf pathogen P. syringae pv. lachrymans resulted in higher systemic expression of the pathogenesisrelated genes encoding for chitinase 1, β-1,3-glucanase, and peroxidase relative to noninoculated, challenged plants. This indicates that Trichoderma induced a potentiated state in the plant enabling it to be more resistant to subsequent pathogen infection.

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