Difference between revisions of "Team:Bordeaux/Problem"
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<p align="justify" style="text-indent: 3vw;"> Since repairing damaged tissues infected by downy mildew is impossible, the main solutions available to vinyards are preventive solutions, mainly through preventing primary infections. This is mainly done by spraying fungicides on the organs that are most infected: leaves and stems. The most efficient preventive treatment was discovered at the end of the 19th century: a solution made of copper sulfate also known as "Bouillie Bordelaise", the only treatment used until the end of the 20th century. Recently, synthetic fungicides have replaced this chemical treatment and more and more research is being done on alternative eco-friendly preventive treatments. </p> | <p align="justify" style="text-indent: 3vw;"> Since repairing damaged tissues infected by downy mildew is impossible, the main solutions available to vinyards are preventive solutions, mainly through preventing primary infections. This is mainly done by spraying fungicides on the organs that are most infected: leaves and stems. The most efficient preventive treatment was discovered at the end of the 19th century: a solution made of copper sulfate also known as "Bouillie Bordelaise", the only treatment used until the end of the 20th century. Recently, synthetic fungicides have replaced this chemical treatment and more and more research is being done on alternative eco-friendly preventive treatments. </p> | ||
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+ | <!-- ---------------------------------------- PLANT IMMUNE SYSTEM ---------------------------------------------------------- --> | ||
+ | <div class="col-lg-10 col-lg-offset-1"> | ||
<h6 align="justify"> Natural defenses of plants </h6> | <h6 align="justify"> Natural defenses of plants </h6> | ||
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<p align="justify" style="text-indent: 3vw;"> Plant Immunization is based on the same principle as human immunization: activating it's natural defenses before contamination by an infectious agent. The concept is simple; it is to put the plant in contact with a molecule able to activate it's natural defenses: <b> an elicitor </b> . In nature there are many elicitors produced by micro-organisms (exogenous elicitors) or by the plant itself when it is attacked (endogenous elicitors). The presence of an elicitor in the plant triggers a series of cellular reactions including the <b> production of molecules to strengthen the resistance of cell walls </b>, but also the <b> production of plant antibiotics </b> such as phytoalexins or defense proteins. These compounds have antifungal and antibacterial properties. The external application of a natural elicitor or a similar synthetic molecule thus results in the production of phytoalexins or defense proteins in the absence of any pathogen. The "immunized" plant is ready to fight back if attacked. First, the cell wall forms a physical barrier which prevents the penetration of most microbes. </p> | <p align="justify" style="text-indent: 3vw;"> Plant Immunization is based on the same principle as human immunization: activating it's natural defenses before contamination by an infectious agent. The concept is simple; it is to put the plant in contact with a molecule able to activate it's natural defenses: <b> an elicitor </b> . In nature there are many elicitors produced by micro-organisms (exogenous elicitors) or by the plant itself when it is attacked (endogenous elicitors). The presence of an elicitor in the plant triggers a series of cellular reactions including the <b> production of molecules to strengthen the resistance of cell walls </b>, but also the <b> production of plant antibiotics </b> such as phytoalexins or defense proteins. These compounds have antifungal and antibacterial properties. The external application of a natural elicitor or a similar synthetic molecule thus results in the production of phytoalexins or defense proteins in the absence of any pathogen. The "immunized" plant is ready to fight back if attacked. First, the cell wall forms a physical barrier which prevents the penetration of most microbes. </p> | ||
<p align="justify"> Then, if some pathogens are able to cross this wall, the infection depends on the ability of the plant to perceive and to trigger defense reactions that would prevent the development of the disease. This recognition is done with certain compounds, known as elicitors from the pathogen or plant. <b> The fixing of an elicitor to a plant cell receptor initiates a cascade of events that leads to the synthesis of defense compounds </b>. The best known are antimicrobial compounds such as <b> phytoalexins </b> and <b> Pathogenesis Related proteins </b>. </p> | <p align="justify"> Then, if some pathogens are able to cross this wall, the infection depends on the ability of the plant to perceive and to trigger defense reactions that would prevent the development of the disease. This recognition is done with certain compounds, known as elicitors from the pathogen or plant. <b> The fixing of an elicitor to a plant cell receptor initiates a cascade of events that leads to the synthesis of defense compounds </b>. The best known are antimicrobial compounds such as <b> phytoalexins </b> and <b> Pathogenesis Related proteins </b>. </p> | ||
− | <p align="justify"> There are two types of defenses: "passive" and "active". | + | |
− | Natural defense reactions of plants are passive when these components were preformed prior to infection. They remain active until the pathogen penetration. | + | <p align="justify"> There are two types of defenses: "passive" and "active". Natural defense reactions of plants are passive when these components were preformed prior to infection. They remain active until the pathogen penetration. Active defenses are induced upon recognition of the pathogen and remain active during infection.</p> <br> |
− | Active defenses are induced upon recognition of the pathogen and remain active during infection.</p> | + | |
− | <br> | + | <img style="width:50vw;height:30vw" src="https://static.igem.org/mediawiki/2015/thumb/a/ab/Bordeaux_MildewVSbeta1%2C3glucan.png/800px-Bordeaux_MildewVSbeta1%2C3glucan.png"> <br> <br> |
− | <img style="width:50vw;height:30vw" | + | |
− | src="https://static.igem.org/mediawiki/2015/thumb/a/ab/Bordeaux_MildewVSbeta1%2C3glucan.png/800px-Bordeaux_MildewVSbeta1%2C3glucan.png"> | + | |
− | <br> | + | |
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<h6 align="justify" > Consequences of the infection </h6> | <h6 align="justify" > Consequences of the infection </h6> | ||
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<p align="justify" style="text-indent: 3vw;"> Delta-viniferin is a <b> grapevine phytoalexin </b> produced during infection by <i> Plasmopara viticola </i>. | <p align="justify" style="text-indent: 3vw;"> Delta-viniferin is a <b> grapevine phytoalexin </b> produced during infection by <i> Plasmopara viticola </i>. | ||
Phytoalexins are antimicrobial and often antioxidative substances synthesized by plants that accumulate rapidly at areas of pathogen infection. Phytoalexins produced in plants act as toxins to the organism. They damage the cell wall, delay maturation, disrupt metabolism or prevent reproduction of the pathogen. </p> | Phytoalexins are antimicrobial and often antioxidative substances synthesized by plants that accumulate rapidly at areas of pathogen infection. Phytoalexins produced in plants act as toxins to the organism. They damage the cell wall, delay maturation, disrupt metabolism or prevent reproduction of the pathogen. </p> |
Revision as of 00:35, 1 August 2015