This document discusses plant defense priming, which enables plants to respond more rapidly and robustly to pathogens. Priming involves accumulating signaling components without activating full resistance. It is accompanied by induced resistance pathways. Priming techniques include chemical treatments and bio-priming with microbes. The molecular mechanisms of priming involve elevated pattern recognition receptors, dormant mitogen-activated protein kinases, and chromatin modifications that provide a stress memory. Priming shows potential for sustainable agriculture by reducing pesticide use through potentiated defenses.
Prime-ome: "A molecular approach towards defense priming"Dhanya AJ
Prime-ome is the entire set of messenger RNA (mRNA) molécules or transcripts, proteins and metabolites produced or modified by an organism or system during the different stages of priming in plants and prime-omics is the study of prime-ome.
Gene for gene system in plant fungus interactionVinod Upadhyay
MOLECULAR CHARACTERIZATION OF GENE FOR GENE SYSTEMS IN PLANT- FUNGUS INTERACTION AND THE APPLICATIONS OF AVIRULENCE GENES IN CONTROL OF PLANT PATHOGENS
Molecular basis of plant resistance and defense responses to pathogensSenthil Natesan
In response to pathogen attack, plants have evolved sophisticated defense mechanisms to delay or arrest pathogen growth.Unlike animals, plants lack a circulating immune system recognizing microbial pathogens. Plant cells are more autonomous in their defense mechanisms and rely on the innate immune capacity of each cell and systemic signals that disseminate from infection sites (Jones and Dangl, 2006). Plant innate immunity consists of preformed physical and chemical barriers (such as leaf hairs, rigid cell walls, pre-existing antimicrobial compounds) and induced defenses. Should an invading microbe successfully breach the pre-formed barriers, it may be recognized by the plant, resulting in the activation of cellular defense responses that stop or restrict further development of the invader.
Systemic acquired resistance (SAR): A novel strategy for plant protection.mohd younus wani
Exclusive reliance on pesticides, fungicides and herbicides resulted in pesticide and herbicide, resistance, pest resurgence, residues, environmental pollution. Plants have developed various resistance mechanisms to help them adapt to pathogen and insect attack (Jones and Dangl, 2006). Systemic acquired resistance (SAR) is a form of induced resistance that is activated throughout a plant after being exposed to elicitors from virulent, avirulent, or nonpathogenic microbes, or artificial chemical stimuli such as chitosan or salicylic acid (SA) (Gozzo and Faoro, 2013).It is a mechanism of induced defense that confers long-lasting protection against a broad spectrum of microorganisms. SAR requires the signal molecule salicylic acid (SA) and is associated with accumulation of pathogenesis-related proteins, which contribute resistance to the plants.
They can be used as fungicide alternative without any threat of developing resistance and being safe and ecofriendly (Najar et al, 2010). The elicitor, β-Amino butyric acid induces greater systemic resistance to mulberry in addition to enhancement in biochemical parameters and NPK contents of mulberry leaves (Mazal, 2014).Therefore, in order to control the diseases of mulberry without adverse effect on environment, humans and silkworms health attention needs to be given to promote SAR chemicals. A model needs to be framed to promote the use of these chemicals in order to make sericulture more profitable. This is an ecofriendly approach of disease and pest management. The chitinase genes of mulberry induced by insect wounding and fungal infection, suggesting that these chitinases help the mulberry plant to cope with the challenges from insects and fungi (Wang et al., 2015). Jasmonic acid (JA) is an important plant defense signal mediating resistance to herbivores.
Presently disease control is largely depends on the use of fungicides, bactericides and insecticides. The hazardous nature of these chemicals on the environment, human health and silkworm strongly necessitates the search for new, harmless means of disease control.Induced resistance like SAR can diminish the use of toxic chemicals for disease control and thus could be proposed as an alternative, non-biocidal, ecologically-friendly approach for plant protection and hence for sustainable Sericulture. Induced resistance is increased expression of Natural defense mechanisms against different pathogens provoked by external factors of various types. Systemic acquired resistance (SAR) is a "whole-plant" resistance response and can be distinguished from other disease resistant responses by both the spectrum of pathogen protection and the associated changes with gene expression.
Prime-ome: "A molecular approach towards defense priming"Dhanya AJ
Prime-ome is the entire set of messenger RNA (mRNA) molécules or transcripts, proteins and metabolites produced or modified by an organism or system during the different stages of priming in plants and prime-omics is the study of prime-ome.
Gene for gene system in plant fungus interactionVinod Upadhyay
MOLECULAR CHARACTERIZATION OF GENE FOR GENE SYSTEMS IN PLANT- FUNGUS INTERACTION AND THE APPLICATIONS OF AVIRULENCE GENES IN CONTROL OF PLANT PATHOGENS
Molecular basis of plant resistance and defense responses to pathogensSenthil Natesan
In response to pathogen attack, plants have evolved sophisticated defense mechanisms to delay or arrest pathogen growth.Unlike animals, plants lack a circulating immune system recognizing microbial pathogens. Plant cells are more autonomous in their defense mechanisms and rely on the innate immune capacity of each cell and systemic signals that disseminate from infection sites (Jones and Dangl, 2006). Plant innate immunity consists of preformed physical and chemical barriers (such as leaf hairs, rigid cell walls, pre-existing antimicrobial compounds) and induced defenses. Should an invading microbe successfully breach the pre-formed barriers, it may be recognized by the plant, resulting in the activation of cellular defense responses that stop or restrict further development of the invader.
Systemic acquired resistance (SAR): A novel strategy for plant protection.mohd younus wani
Exclusive reliance on pesticides, fungicides and herbicides resulted in pesticide and herbicide, resistance, pest resurgence, residues, environmental pollution. Plants have developed various resistance mechanisms to help them adapt to pathogen and insect attack (Jones and Dangl, 2006). Systemic acquired resistance (SAR) is a form of induced resistance that is activated throughout a plant after being exposed to elicitors from virulent, avirulent, or nonpathogenic microbes, or artificial chemical stimuli such as chitosan or salicylic acid (SA) (Gozzo and Faoro, 2013).It is a mechanism of induced defense that confers long-lasting protection against a broad spectrum of microorganisms. SAR requires the signal molecule salicylic acid (SA) and is associated with accumulation of pathogenesis-related proteins, which contribute resistance to the plants.
They can be used as fungicide alternative without any threat of developing resistance and being safe and ecofriendly (Najar et al, 2010). The elicitor, β-Amino butyric acid induces greater systemic resistance to mulberry in addition to enhancement in biochemical parameters and NPK contents of mulberry leaves (Mazal, 2014).Therefore, in order to control the diseases of mulberry without adverse effect on environment, humans and silkworms health attention needs to be given to promote SAR chemicals. A model needs to be framed to promote the use of these chemicals in order to make sericulture more profitable. This is an ecofriendly approach of disease and pest management. The chitinase genes of mulberry induced by insect wounding and fungal infection, suggesting that these chitinases help the mulberry plant to cope with the challenges from insects and fungi (Wang et al., 2015). Jasmonic acid (JA) is an important plant defense signal mediating resistance to herbivores.
Presently disease control is largely depends on the use of fungicides, bactericides and insecticides. The hazardous nature of these chemicals on the environment, human health and silkworm strongly necessitates the search for new, harmless means of disease control.Induced resistance like SAR can diminish the use of toxic chemicals for disease control and thus could be proposed as an alternative, non-biocidal, ecologically-friendly approach for plant protection and hence for sustainable Sericulture. Induced resistance is increased expression of Natural defense mechanisms against different pathogens provoked by external factors of various types. Systemic acquired resistance (SAR) is a "whole-plant" resistance response and can be distinguished from other disease resistant responses by both the spectrum of pathogen protection and the associated changes with gene expression.
Detailed description on the mode of actions of various phytoalexins, mechanisms involved phtyoalexin formation, various types of phytoalexins, its functions
Plants have array of defense response against biotic stresses which could be either structural reinforcement, release of chemicals, and defense gene expression against invading organisms. The physical barriers are trichoms, waxy cuticle, thick cell wall. Once the pathogen overcomes the first line of defense, basal or innate defense response comes into play. Pathogens secrete some conserved molecules known as Pathogen Associated Molecular Pattern (PAMP/MAMP), which are recognized by transmembrane receptors present in the plasma membrane and initiate a series of signal cascade reaction which ultimately leads to activation of various defense related genes. Apart from inducing the expression of defense related genes, it also triggers a hypersensitive reaction (HR) which cause deliberate cell death at the site of infection and limit the pathogen access to water and nutrient by sacrificing a few cells in order to save the rest of the plant. Once HR is triggered, plant tissue may become highly resistant to a broad range of pathogens for an extended period of time. This phenomenon is called Systemic Acquired Resistance (SAR).
Plants respond to herbivory is a similar manner as described above. The biochemical mechanisms of defense against the herbivores are wide-ranging, highly dynamic, and are mediated both by direct and indirect defenses. The defensive compounds are either produced constitutively or in response to plant damage, and affect feeding, growth, and survival of herbivores. In addition, plants also release volatile organic compounds that attract the natural enemies of the herbivores. These strategies either act independently or in conjunction with each other. However, our understanding of these defensive mechanisms is still limited. Induced resistance could be exploited as an important tool for the pest management to minimize the amounts of insecticides used for pest control. Host plant resistance to insects, particularly, induced resistance, can also be manipulated with the use of chemical elicitors of secondary metabolites, which confer resistance to insects. By understanding the mechanisms of induced resistance, we can predict the herbivores that are likely to be affected by inducing responses. The elicitors of induced responses can be sprayed on crop plants to build up the natural defense system against damage caused by herbivores. The induced responses can also be genetically engineered, so that the defensive compounds are constitutively produced in plants challenged by the herbivory. Induced resistance can be exploited for developing crop cultivars, which readily produce the inducible response upon mild infestation, and can act as one of components of integrated pest management for sustainable crop production.
The study of pathogenomics attempts to utilize genomic and metagenomics data gathered from high through-put technologies to understand microbe diversity and interaction as well as host-microbe interactions involved in causing the disease. Pathogenomics researchers are generating and analyzing genome sequences of diverse bacterial, oomycete, fungal and viral pathogens to identify genetic sources of virulence, understand differences observed among related pathogens, guide the development of diagnosis tools capable of discriminating among specific strains, reveal sources of host resistance and understand the dynamics of host-microbe interactions and the diseases they cause .
Detailed description on the mode of actions of various phytoalexins, mechanisms involved phtyoalexin formation, various types of phytoalexins, its functions
Plants have array of defense response against biotic stresses which could be either structural reinforcement, release of chemicals, and defense gene expression against invading organisms. The physical barriers are trichoms, waxy cuticle, thick cell wall. Once the pathogen overcomes the first line of defense, basal or innate defense response comes into play. Pathogens secrete some conserved molecules known as Pathogen Associated Molecular Pattern (PAMP/MAMP), which are recognized by transmembrane receptors present in the plasma membrane and initiate a series of signal cascade reaction which ultimately leads to activation of various defense related genes. Apart from inducing the expression of defense related genes, it also triggers a hypersensitive reaction (HR) which cause deliberate cell death at the site of infection and limit the pathogen access to water and nutrient by sacrificing a few cells in order to save the rest of the plant. Once HR is triggered, plant tissue may become highly resistant to a broad range of pathogens for an extended period of time. This phenomenon is called Systemic Acquired Resistance (SAR).
Plants respond to herbivory is a similar manner as described above. The biochemical mechanisms of defense against the herbivores are wide-ranging, highly dynamic, and are mediated both by direct and indirect defenses. The defensive compounds are either produced constitutively or in response to plant damage, and affect feeding, growth, and survival of herbivores. In addition, plants also release volatile organic compounds that attract the natural enemies of the herbivores. These strategies either act independently or in conjunction with each other. However, our understanding of these defensive mechanisms is still limited. Induced resistance could be exploited as an important tool for the pest management to minimize the amounts of insecticides used for pest control. Host plant resistance to insects, particularly, induced resistance, can also be manipulated with the use of chemical elicitors of secondary metabolites, which confer resistance to insects. By understanding the mechanisms of induced resistance, we can predict the herbivores that are likely to be affected by inducing responses. The elicitors of induced responses can be sprayed on crop plants to build up the natural defense system against damage caused by herbivores. The induced responses can also be genetically engineered, so that the defensive compounds are constitutively produced in plants challenged by the herbivory. Induced resistance can be exploited for developing crop cultivars, which readily produce the inducible response upon mild infestation, and can act as one of components of integrated pest management for sustainable crop production.
The study of pathogenomics attempts to utilize genomic and metagenomics data gathered from high through-put technologies to understand microbe diversity and interaction as well as host-microbe interactions involved in causing the disease. Pathogenomics researchers are generating and analyzing genome sequences of diverse bacterial, oomycete, fungal and viral pathogens to identify genetic sources of virulence, understand differences observed among related pathogens, guide the development of diagnosis tools capable of discriminating among specific strains, reveal sources of host resistance and understand the dynamics of host-microbe interactions and the diseases they cause .
Proteomic analysis of the interaction between the plant growth promoting fhiz...kys9723331
Plant growth-promoting rhizobacteria (PGPR) facilitate the plant growth and enhance their
induced systemic resistance (ISR) against a variety of environmental stresses. In this study,
we carried out integrative analyses on the proteome, transcriptome, and metabolome to investigate
Arabidopsis root and shoot responses to the well-known PGPR strain Paenibacillus
polymyxa (P. polymyxa) E681. Shoot fresh and root dry weights were increased, whereas root
length was decreased by treatment with P. polymyxa E681. 2DE approach in conjunction
with MALDI-TOF/TOF analysis revealed a total of 41 (17 spots in root, 24 spots in shoot)
that were differentially expressed in response to P. polymyxa E681. Biological process- and
molecular function-based bioinformatics analysis resulted in their classification into seven different
protein groups. Of these, 36 proteins including amino acid metabolism, antioxidant,
defense and stress response, photosynthesis, and plant hormone-related proteins were upregulated,
whereas five proteins including three carbohydrate metabolism- and one amino
acid metabolism-related, and one unknown protein were down-regulated, respectively. A good
correlation was observed between protein and transcript abundances for the 12 differentially
expressed proteins during interactions as determined by qPCR analysis. Metabolite analysis
using LC-MS/MS revealed highly increased levels of tryptophan, indole-3-acetonitrile (IAN),
indole-3-acetic acid (IAA), and camalexin in the treated plants. Arabidopsis plant inoculated
P. polymyxa E681 also showed resistance to Botrytis cinerea infection. Taken together these
results suggest that P. polymyxa E681 may promote plant growth by induced metabolism and
activation of defense-related proteins against fungal pathogen.
The current study investigated the immunomodulatory
potential of ethyl acetate soluble supernatant of
Lactobacillus casei (LC-EAS) in vitro. The effect of
LC-EAS on nitric oxide release was analyzed in RAW
264.7 cells, wherein, an inhibition in nitric oxide production
through suppression of inducible nitric oxide synthase
mRNA expression was observed. Evaluation of LC-EAS
on LPS-induced peripheral blood mononuclear cells
showed a down-regulation in TNF-a and IL-6 genes and an
upregulation of IL-10. An inhibition in the protein
expression of NF-kB, ERK1/2 and STAT3 phosphorylation
confirms the immunomodulatory potential of LC-EAS. The
effect of LC-EAS on in vitro intestinal epithelial cells was
investigated using HT-29 human colon adenocarcinoma
cancer cells. LC-EAS exhibited an inhibition of NF-jB and
ERK1/2 phosphorylation, whereas STAT3 phosphorylation
was unregulated. To evaluate the downstream target of
STAT3 upregulation, expression of the intestinal trefoil
factor TFF3 which is a NF-jB regulator and STAT3
downstream target was studied. LC-EAS was observed to
elevate TFF3 mRNA expression. Overall the study shows
that the anti-inflammatory potential of LC-EAS is through
inhibition of NF-kB in different cell types.
Identification of defense proteins in pearl millet seeds effective against Ma...ICRISAT
Pearl millet leaf blast is caused by Magnaporthe grisea (Anamorph, Pyricularia grisea) has been recently emerged as devastating disease with economic significance in India. It is well-known that host plant resistance is the most economical strategy to effectively manage this disease; hence, identification of resistance sources for blast disease is important to incorporate resistance genes into elite breeding lines. On the other hand, fungal cell wall is a multi-layered, in which chitin and glucan are the major polysaccharide constituents (Figure 1). In this view, chitinases and glucanases gain significant attention as antifungal enzymes. These were produced as pathogenesis related (PR) hydrolses in plants with constitutive expression in seeds, leaves, flowers, tubers and induced upon pathogen invasion. They exert their defensive role by decomposing the fungal cell wall polysaccharides chitin and glucan into respective monomers as N-Acetyl D-glucosamine and D-glucose residues (Prasannath, 2017). Whereas, protease inhibitors (PIs) are known to participate in defensive role by inhibiting the extracellular protease activity secretes from actively growing fungal mycelia as well as cysteine proteases involved in the chitin synthase activity (Joshi et al., 1998). Hence, the present study is focused on the screening of chitinases, glucanases and cysteine protease inhibitors in ten pearl millet seed proteins with differential disease resistance and evaluation of their anti fungal efficacy against growth of P. grisea (Pg 45), prevalent isolate in Hyderabad, Telangana region.
2024.06.01 Introducing a competency framework for languag learning materials ...Sandy Millin
http://sandymillin.wordpress.com/iateflwebinar2024
Published classroom materials form the basis of syllabuses, drive teacher professional development, and have a potentially huge influence on learners, teachers and education systems. All teachers also create their own materials, whether a few sentences on a blackboard, a highly-structured fully-realised online course, or anything in between. Despite this, the knowledge and skills needed to create effective language learning materials are rarely part of teacher training, and are mostly learnt by trial and error.
Knowledge and skills frameworks, generally called competency frameworks, for ELT teachers, trainers and managers have existed for a few years now. However, until I created one for my MA dissertation, there wasn’t one drawing together what we need to know and do to be able to effectively produce language learning materials.
This webinar will introduce you to my framework, highlighting the key competencies I identified from my research. It will also show how anybody involved in language teaching (any language, not just English!), teacher training, managing schools or developing language learning materials can benefit from using the framework.
Honest Reviews of Tim Han LMA Course Program.pptxtimhan337
Personal development courses are widely available today, with each one promising life-changing outcomes. Tim Han’s Life Mastery Achievers (LMA) Course has drawn a lot of interest. In addition to offering my frank assessment of Success Insider’s LMA Course, this piece examines the course’s effects via a variety of Tim Han LMA course reviews and Success Insider comments.
Welcome to TechSoup New Member Orientation and Q&A (May 2024).pdfTechSoup
In this webinar you will learn how your organization can access TechSoup's wide variety of product discount and donation programs. From hardware to software, we'll give you a tour of the tools available to help your nonprofit with productivity, collaboration, financial management, donor tracking, security, and more.
Model Attribute Check Company Auto PropertyCeline George
In Odoo, the multi-company feature allows you to manage multiple companies within a single Odoo database instance. Each company can have its own configurations while still sharing common resources such as products, customers, and suppliers.
Read| The latest issue of The Challenger is here! We are thrilled to announce that our school paper has qualified for the NATIONAL SCHOOLS PRESS CONFERENCE (NSPC) 2024. Thank you for your unwavering support and trust. Dive into the stories that made us stand out!
Macroeconomics- Movie Location
This will be used as part of your Personal Professional Portfolio once graded.
Objective:
Prepare a presentation or a paper using research, basic comparative analysis, data organization and application of economic information. You will make an informed assessment of an economic climate outside of the United States to accomplish an entertainment industry objective.
Instructions for Submissions thorugh G- Classroom.pptxJheel Barad
This presentation provides a briefing on how to upload submissions and documents in Google Classroom. It was prepared as part of an orientation for new Sainik School in-service teacher trainees. As a training officer, my goal is to ensure that you are comfortable and proficient with this essential tool for managing assignments and fostering student engagement.
Unit 8 - Information and Communication Technology (Paper I).pdfThiyagu K
This slides describes the basic concepts of ICT, basics of Email, Emerging Technology and Digital Initiatives in Education. This presentations aligns with the UGC Paper I syllabus.
Embracing GenAI - A Strategic ImperativePeter Windle
Artificial Intelligence (AI) technologies such as Generative AI, Image Generators and Large Language Models have had a dramatic impact on teaching, learning and assessment over the past 18 months. The most immediate threat AI posed was to Academic Integrity with Higher Education Institutes (HEIs) focusing their efforts on combating the use of GenAI in assessment. Guidelines were developed for staff and students, policies put in place too. Innovative educators have forged paths in the use of Generative AI for teaching, learning and assessments leading to pockets of transformation springing up across HEIs, often with little or no top-down guidance, support or direction.
This Gasta posits a strategic approach to integrating AI into HEIs to prepare staff, students and the curriculum for an evolving world and workplace. We will highlight the advantages of working with these technologies beyond the realm of teaching, learning and assessment by considering prompt engineering skills, industry impact, curriculum changes, and the need for staff upskilling. In contrast, not engaging strategically with Generative AI poses risks, including falling behind peers, missed opportunities and failing to ensure our graduates remain employable. The rapid evolution of AI technologies necessitates a proactive and strategic approach if we are to remain relevant.
Home assignment II on Spectroscopy 2024 Answers.pdf
Priming for enhanced defence during Plant-Pathogen Intraction
1. PRIMING FOR ENHANCED DEFENSE DURING
PLANT-PATHOGEN INTERACTION
Dr. Rakesh Punia
Assistant Scientist
1
2. 2
CONTENTS
Priming
Induced Resistance in the context of Priming
Priming techniques
Molecular mechanism of Defense priming
Chromatin modification
Application of priming in plant-pathogen interaction
Advantages and Limitations of Priming
Conclusions
Future prospects
3. 3
Priming is the phenomenon that enables cells to respond to
much lower levels of a stimulus in a more rapid and robust
manner than non-primed cells.
Cell priming involves accumulation of signaling
components that are not used until challenge exposure to
stress.
PRIMING
6. Induced Systemic Resistance (ISR)
Most of the Bio-priming agent
follow ISR.
Jasmonic acid (JA) and/or Ethylene
(ET) mediated.
Lox gene activation is
characteristic.
(Perzalli et al., 2011)
Induced Resistance in context of Priming
Systemic Acquired Resistance (SAR)
Chemical priming agent follow this
pathway.
Salicylic acid (SA) mediated.
Pathogenesis Related protein 1
(PR1)expression is characteristic.
(Perzalli et al., 2011, Conrath et al., 2015)
6
Priming is accompanied by Induced resistance as:
7. PRIMING TECHNIQUES
Hydro priming: Achieved by soaking seeds in water.
Osmo priming: By adding osmotica like mannitol, poly ethylene
glycerol (PEG).
Solid matrix priming: Matrix carriers like calcinated clay, vermiculite.
Chemo priming: By Benzothiadiazole (BTH), β-amino butyric acid
(BABA), Azealic acid, Pipecolic acid.
Halo priming: Using salts of sulphate, chloride, nitrate.
Bio-priming: By Trichoderma spp., Plant growth promoting
Rhizobacteria (PGPR), Plant extracts.
7
8. MOLECULAR MECHANISMS OF DEFENSE PRIMING
Elevated
Levels of
Pattern-
Recognition
Receptors
Dormant
Mitogen-
Activated
Protein
Kinases
Chromatin
Modification
8
(Conrath et al., 2015)
9. Mechanism of Defense Priming
NAIVE
PRIMED
PRIMED and
CHALLENGED
Priming for enhanced defense
Challenging stimulus
9
(Conrath et al., 2015)
10. • Priming for enhanced defense comprises spotting of
diverse PRRs to the plasma membrane thereby enhancing
the plant’s responsiveness to different Pathogen
Associated Molecular Patterns (PAMPs) and Damage
Associated Molecular Patterns (DAMPs).
10
Enhanced level of Pattern Recognition Receptors
(PRRs)
PAMPs and DAMPs
flg22
Peptidoglycon
EF-Tu
Chitin
Chitosan
Oligogalacturonic acid (OGs)
PRRs
FLS 2 and BAK1 ------
LYM ------
EFR ------
CERK 1 ------
CBPK ------
WAK ------
BACTERIAL
FUNGAL
DAMPs
Plant cell
surface
11. Tateda et al., 2014
FLS2 and BAK1 protein level after BTH treatment on the leaves of A. thaliana.
Arabidopsis
thaliana
11
14. Dormant Mitogen-Activated Protein
Kinases
Defense responses are regulated by a complex signaling network
that includes MAPKs cascades after plant recognition of
pathogens by PRRs .
MAPKs can control the synthesis and/or signaling of defense
hormones, reprogram gene expression through phosphorylation
of target proteins, including enzymes and transcription factors.
14
16. PLANT MAPKs CASCADES
MAPKKKs
MEKK-like kinases
MEKK1, MAPKKK3
( MAPKKKs upstream of
MAPKKs in plant MAPK
cascades)
(
Raf-like members
MAPKKs/MEKs
Group A
MKK1, MKK2, MKK6
(MKK1 and MKK2 act upstream
of MPK4 in response to cold,
salinity, and pathogens )
Group B
MKK3
(Upstream of MPK6 in
regulating JA signalling).
Group C
MKK4 and MKK5
( upstream of MPK3 and
MPK6)
Group D
MKK7, MKK8, MKK9
(MKK7 or MKK9 activates
MPK3 and MPK6)
MAPKs
Group A
MAPK3 and MAPK6
(Ortholog of SAMK,SIMK, SIPK
and WIPK , involved in biotic and
abiotic stresses response,
growth- development )
Group B
MAPK4 and MAPK11
(Pathogen defense and abiotic
stress responses, cell division)
14Meng et al., 2013
19. BTH induces accumulation of MPK3 and MPK6 transcripts and proteins but does not
elicit dual TEY motif phosphorylation.
Beckers et al., 2009
17
BTH treated
BTH untreated
BTH treated
BTH untreated
20. Attenuation of Priming for Potentiated
Defense Gene Activation in MPK-Deficient
Plants.
20
Beckers et al., 2009
Dual TEY Phosphorylation Is Enhanced
in BTH-Primed Leaves after Dip
Inoculation with P. syringae pv.
maculicola.
Stress
(P. s pv. maculicola)
min
21. Attenuation of BTH-IR, SAR, and Infection-Induced Dual TEY Phosphorylation in mpk
Mutants.
21
Beckers et al., 2009
P.syringae pv. maculicola, 2h
Mock
BTH treated
22. Rewiring Mitogen-Activated Protein Kinase Cascade by Positive
Feedback Confers Potato Blight Resistance
22
Schematic representation of mechanism
of immune responses in transgenic
potato plants
Chihiro Yamamizo, Kuchimura, Kobayashi, Katou, Kazuhito
Plant Physiology, 2006, Vol. 140, pp. 681–692,
1 2 43 5 (h)
/StMEK1
23. Transgenic potato plants indicate elevation of MAPK activity and up-regulation of defense-
related genes during compatible P. infestans-potato interactions
23
Chihiro et al., 2006
24. Transgenic potato plants harboring PVS3::StMEK1DD show resistance to P. infestans 24
Chihiro et al., 2006
25. CHROMATIN MODIFICATION
Chromatin consists of DNA and histone proteins and
pivotal to eukaryotic gene regulation .
DNA (methylation) and histones (methylation, acetylation)
both are modified during gene regulation .
Acetylation of histone lysine residues slacks the interaction
and loosens the ionic DNA-histone interaction, and
provides docking sites for trancription activators (gene
loading).
25
26. Transcript abundance and histone modifications after priming and potentiated activation
WRKY29 transcription factor gene.
A. thaliana 100mM BTH/WP
72h
Primed plant Leaves collection
P.Syringae pv. maculicola
3h
26
Chromatin modification acts as a memory for systemic
acquired resistance in the plant stress response
Michal Jaskiewicz, Conrath & Christoph
EMBO reports (2011) 12, 50–55
27. Application of Defense Priming in Plant-
Pathogen Interaction
Chemical agent
• BABA
• BTH (Boost R)
• Probenazole
• Acibenzolar–Smethyl
(Actigard)
• Fosetyl Al
• Metalaxyl (Ridomil)
• Strobilurin (Azoxystrobin)
• Pipecolic acid
• Azealic acid
Bio-priming agent
• Trichoderma asperellum
(Remedier R)
• P. fluorescens + T. harzianum
(PB-3)
• Bacillus subtilis (Taegro R)
• Trichoderma fertile
(TrichoPlusTM)
• Mycorrhiza (MycoGrow TM)
• Chitosan
27
28. Oligogalacturonic Acid and Chitosan Reduce Stomatal Aperture by Inducing
the Evolution of Reactive Oxygen Species from Guard Cells of Tomato
Lee , Hyunjung Choi,and SuJeoung Suh
Effects of OGA on stomatal opening in tomato leaf epidermis
OGA 5µg/ml, Catalase 3mg/ml, EGTA 2mM
28
29. Effect of chitosan on stomatal opening in tomato leaf epidermis
Control Chitosan Chitosan + Cat Chitosan + Asc
29
Lee et al., 1999
Chitosan-induced production of H2O2 by guard cells of tomato leaf (Fluores. DCF-DA microscpy)
3 mg/mL catalase , 10 mM ascorbic acid, 1ooµg/ml Chitosan
30. M. Perazzolli , B.Roatti , E. Bozza a and I. Pertot
T39 @ 8g/L, BTH @ 0.5g/l, Cu (OH)2 @ 1.42g/l 30
Local effect
Systemic effect
Post inoculationPre inoculation
L=Local effect S =Systemic effect
31. 31
Perazzolli et al., 2011
Pre inoculation
Post inoculation
L=Local effect
S =Systemic effect
32. Reduction of Disease Progression in BTH-Treated Plants.
Germination rate, formation of appressoria, frequency of penetration,
and formation of mature primary and secondary haustoria were
determined for BTH-treated (0.3 mM) and control plants (set to
100%). Inoculation was performed 4 days after chemical treatment,
and the development of 300 conidia was monitored
Phenotypic Expression of BTH (@ 30g/ha) lnduced Resistance
against E. graminis tritici .
35% symptoms reduction and 18% increase in yield w.r.t.
control. Plants were photographed 2 months after treatment.
Control BTH treated
Jorn Gorlach, Sandra Volrath and John Ryals
The Plant Cell, Vol. 8, 629-643, April 1996
32
BTH treated
33. BTH-Mediated Resistance Responses.
(A) Infection 10 DPI with E. g. tritici. BTH (0.5 mM) and control.
(B) Autofluorescence of a BTH-mediated HR of an attacked cell 48 hr PI
Infection sites in control (C) and BTH-treated (D) leaves 48hr PI
Infection sites in control (E) and BTH-treated (F) leaves 72hrPI.
Induction of WCI Genes by BTH Treatment.
33
Gorlach et al., 1996
34. Plant growth-promoting rhizobacteria mediate induced systemic resistance in rice against
bacterial leaf blight caused by Xanthomonas oryzae pv. oryzae
Chithrashree , Udayashankar and C. Srinivas
Figures in parentheses represent percentage protection offered.
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36. 36
Limitations
Priming compounds should be
applied before pathogen infection.
Priming compounds do not tend to
be highly specific, which can be an
advantage or a disadvantage
depending on the situation.
A major limitation of chemical
priming compounds is their dose
application because improper dose
may cause phytotoxicity and can
exhaust the plant itself.
Advantages and Limitations of Defense Priming
Advantages
An ecofriendly approach of
disease management.
Reduces the application rate
and frequency of chemical
pesticides.
Biopriming agents also helps in
Plant growth and development
so maintain the quality of
product without energy cost of
plant.
37. Priming for enhanced defense accompanies by SAR and ISR.
Molecular mechanisms in the primed innate immune includes elevated
levels of PRRs and dormant cellular signaling enzymes (MPKs), transcription
coactivator function, and histones modifications in defense gene promoters
which provide stress memory.
We expect the emerging knowledge will increasingly translate defense
priming to practice, thereby improving sustainable agriculture .
We believe that priming compounds will have an impact on future
agricultural practices by providing the farmer with new options for disease
management in respect to both application rate and frequency.
CONCLUSION
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38. FUTURE PROSPECTS
Development of functional genomic tools for enhanced resistance -
interactions between defense signaling and other plant processes.
Designing the new tools and techniques that can be used for
identification of the priming activators.
Deciphering the impact of endophytes (beneficial microbes that
live inside a plant) in priming and induced immunity.
Development and identification of new priming activators for the
management of disease.
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