Electrical Stimulation Enhances Plant Defense Response in Grapevine through Salicylic Acid-Dependent Defense Pathway

Concern over environmental pollution generated by chemical fungicides has led to the introduction of alternative pest management strategies to chemical fungicide application. One of those strategies is the induction of plant defense response by an abiotic elicitor. In the present study, field-grown grapevines were subjected to electrical stimulation using a solar panel from two weeks before flowering to harvest in the 2016 and 2020 growing seasons. In both years, electrical stimulation decreased the incidence of gray mold and/or ripe rot on bunches and downy mildew on leaves of the field-grown grapevine. Transcription of a gene encoding β-1,3-glucanase but not class IV chitinase in leaves of potted grapevine seedlings was upregulated 20 days after electrical stimulation, suggesting that electrical stimulation acts as an abiotic elicitor of plant defense response to fungal diseases. The gene expression of PR1 but not PDF1.2 was upregulated in Arabidopsis plants subjected to electrical stimulation. On the other hand, PR1 gene expression was not induced in salicylic acid (SA)-insensitive Arabidopsis mutant npr1-5 subjected to electrical stimulation. Taken together, electrical stimulation is responsible for plant defense response through the SA-dependent defense pathway. These findings would help us develop a novel and innovative practical technique that uses electrical stimulation in integrated pest management.

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The ability to manipulate ROS metabolism in pepper may affect aphid virulence

Horticulture Research ◽

10.1038/s41438-019-0231-6 ◽

2020 ◽

Vol 7 (1) ◽

Cited By ~ 2

Author(s):

Mengjing Sun ◽

Roeland E. Voorrips ◽

Martijn van Kaauwen ◽

Richard G. F. Visser ◽

Ben Vosman

Keyword(s):

Gene Expression ◽

Plant Defense ◽

Myzus Persicae ◽

Defense Response ◽

Plant Defense Response ◽

Whole Genome ◽

Ros Production ◽

Ros Scavenging ◽

Ros Metabolism ◽

Two Populations

AbstractMyzus persicae has severe economic impact on pepper (Capsicum) cultivation. Previously, we identified two populations of M. persicae, NL and SW, that were avirulent and virulent, respectively on C. baccatum accession PB2013071. The transcriptomics approach used in the current study, which is the first study to explore the pepper−aphid interaction at the whole genome gene expression level, revealed genes whose expression is differentially regulated in pepper accession PB2013071 upon infestation with these M. persicae populations. The NL population induced ROS production genes, while the SW population induced ROS scavenging genes and repressed ROS production genes. We also found that the SW population can induce the removal of ROS which accumulated in response to preinfestion with the NL population, and that preinfestation with the SW population significantly improved the performance of the NL population. This paper supports the hypothesis that M. persicae can overcome the resistance in accession PB2013071 probably because of its ability to manipulate plant defense response especially the ROS metabolism and such ability may benefit avirulent conspecific aphids.

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Pathogen-Induced Accumulation of an Ellagitannin Elicits Plant Defense Response

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi-12-11-0306 ◽

2012 ◽

Vol 25 (11) ◽

pp. 1430-1439 ◽

Cited By ~ 17

Author(s):

Alicia Mamaní ◽

María Paula Filippone ◽

Carlos Grellet ◽

Björn Welin ◽

Atilio Pedro Castagnaro ◽

...

Keyword(s):

Salicylic Acid ◽

Plant Defense ◽

Defense Response ◽

Foliar Application ◽

Pathogen Resistance ◽

Plant Defense Response ◽

Plant Leaves ◽

Incompatible Interaction ◽

Callose Deposition ◽

Common Plant

In an incompatible interaction between Colletotrichum fragariae and strawberry plants, the accumulation of phenolic compounds in plant leaves was observed. A particularly abundant penta-esterified ellagitannin that accumulated in response to pathogen attack was identified as 1-0-galloyl-2,3;4,6-bis-hexahydroxydiphenoyl-β-d-glucopyranose (HeT) by mass spectroscopy and nuclear magnetic resonance. Foliar application of purified HeT prior to inoculation with a virulent pathogen was shown to increase resistance toward C. acutatum in strawberry plants and to Xanthomonas citri subsp. citri in lemon plants. The induced resistance in strawberry was associated with a rapid oxidative burst, callose deposition, a transient increase of salicylic acid in phloem, and induction of gene expression responsive to salicylic acid. Results obtained suggested that HeT could be a common plant defense response molecule capable of inducing pathogen resistance in different plant species.

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Root exposure to apple replant disease soil triggers local defense response and rhizoplane microbiome dysbiosis

FEMS Microbiology Ecology ◽

10.1093/femsec/fiab031 ◽

2021 ◽

Author(s):

Alicia Balbín-Suárez ◽

Samuel Jacquiod ◽

Annmarie-Deetja Rohr ◽

Benye Liu ◽

Henryk Flachowsky ◽

...

Keyword(s):

Gene Expression ◽

Plant Defense ◽

Defense Response ◽

Soil Column ◽

Soil Layer ◽

Soil Microbiome ◽

Control Soil ◽

Apple Rootstocks ◽

Apple Replant Disease ◽

Replant Disease

Abstract A soil column split-root experiment was designed to investigate the ability of apple replant disease (ARD) causing agents to spread in soil. ‘M26’ apple rootstocks grew into a top layer of Control soil, followed by a barrier-free split-soil layer (Control soil/ARD soil). We observed a severely reduced root growth, concomitant with enhanced gene expression of phytoalexin biosynthetic genes and phytoalexin content in roots from ARD soil, indicating a pronounced local plant defense response. Amplicon sequencing (bacteria, archaea, fungi) revealed local shifts in diversity and composition of microorganisms in the rhizoplane of roots from ARD soil. An enrichment of OTUs affiliated to potential ARD fungal pathogens (Ilyonectria and Nectria sp.) and bacteria frequently associated with ARD (Streptomyces, Variovorax) was noted. In conclusion, our integrated study supports the idea of ARD being local and not spreading into surrounding soil, as only the roots in ARD soil were affected in terms of growth, phytoalexin biosynthetic gene expression, phytoalexin production, and altered microbiome structure. This study further reinforces the microbiological nature of ARD, being likely triggered by a disturbed soil microbiome enriched with low mobility ARD-causing agents that induce a strong plant defense and rhizoplane microbiome dysbiosis, concurring with root damage.

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Deletion of the SACPD-C Locus Alters the Symbiotic Relationship Between Bradyrhizobium japonicum USDA110 and Soybean, Resulting in Elicitation of Plant Defense Response and Nodulation Defects

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi-08-16-0173-r ◽

2016 ◽

Vol 29 (11) ◽

pp. 862-877 ◽

Cited By ~ 6

Author(s):

Hari B. Krishnan ◽

Alaa A. Alaswad ◽

Nathan W. Oehrle ◽

Jason D. Gillman

Keyword(s):

Plant Defense ◽

Defense Response ◽

Acyl Carrier Protein ◽

Defense Responses ◽

Nodule Development ◽

Plant Defense Response ◽

Wild Type ◽

Two Dimensional Gel Electrophoresis ◽

Symbiotic Associations ◽

Soybean Nodule

Legumes form symbiotic associations with soil-dwelling bacteria collectively called rhizobia. This association results in the formation of nodules, unique plant-derived organs, within which the rhizobia are housed. Rhizobia-encoded nitrogenase facilitates the conversion of atmospheric nitrogen into ammonia, which is utilized by the plants for its growth and development. Fatty acids have been shown to play an important role in root nodule symbiosis. In this study, we have investigated the role of stearoyl-acyl carrier protein desaturase isoform C (SACPD-C), a soybean enzyme that catalyzes the conversion of stearic acid into oleic acid, which is expressed in developing seeds and in nitrogen-fixing nodules. In-depth cytological investigation of nodule development in sacpd-c mutant lines M25 and MM106 revealed gross anatomical alteration in the sacpd-c mutants. Transmission electron microscopy observations revealed ultrastructural alterations in the sacpd-c mutants that are typically associated with plant defense response to pathogens. In nodules of two sacpd-c mutants, the combined jasmonic acid (JA) species (JA and the isoleucine conjugate of JA) were found to be reduced and 12-oxophytodienoic acid (OPDA) levels were significantly higher relative to wild-type lines. Salicylic acid levels were not significantly different between genotypes, which is divergent from previous studies of sacpd mutant studies on vegetative tissues. Soybean nodule phytohormone profiles were very divergent from those of roots, and root profiles were found to be almost identical between mutant and wild-type genotypes. The activities of antioxidant enzymes, ascorbate peroxidase, and superoxide dismutase were also found to be higher in nodules of sacpd-c mutants. PR-1 gene expression was extremely elevated in M25 and MM106, while the expression of nitrogenase was significantly reduced in these sacpd-c mutants, compared with the parent ‘Bay’. Two-dimensional gel electrophoresis and matrix-assisted laser desorption-ionization time of flight mass spectrometry analyses confirmed sacpd-c mutants also accumulated higher amounts of pathogenesis-related proteins in the nodules. Our study establishes a major role for SACPD-C activity as essential for proper maintenance of soybean nodule morphology and physiology and indicates that OPDA signaling is likely to be involved in attenuation of nodule biotic defense responses.

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