Systemic acquired resistance SAR

Local infection of a plant will stimulate the development of natural defense mechanisms often resulting in an immune reaction toward a variety of pathogens. Certain chemicals can also trigger the same biochemical reactions in plants. Among the chemicals found to induce this systemic acquired resistance (SAR) are thieno[2,3-rf [ 1,2,3]-thiadiazoles 195 <1999JPR341>. 

Systemic Acquired Resistance. SAR is the induction of a transient long-distance (translocated) defence response to fungal attack that is distinct from the local production of phytoalexins. The transient nature of SAR is important and has likely been selected in the course of evolution as a corollary to the energy demands that are made on the plant by the permanent mobilisation of resistance mechanisms. However, plants challenged by fungi are sensitised to subsequent attack and the speed of their SAR response is increased. 

APX (— elevates H202) [induces plant defence responses plant systemic acquired resistance (SAR)]... 

A localized predisposing infection with a necrotizing pathogen usually results in a type of resistance referred to as systemic acquired resistance (SAR). SAR has been described for a large number of plant species [5,6,42]. 

Besides jasmonates, some other compounds used for inducing systemic acquired resistance (SAR) in plants have now been found to be elicitors in plant cell cultures (Figure 6.4). 

Either biotic or abiotic stress, or a combination of both, increases the production of phenolic compounds. Different kinds of stress may affect different parts of the Systemic Acquired Resistance (SAR) pathways and may determine whether (SA), (JA), ethylene or more than one signaling compound is employed in different plant species [20]. Simple phenolic acids are signaling molecules involved in plant-microbe interactions. Methyl salicylate is synthesized in the site of primary infection and protects the plant from the spread of infection and future attack [21]. 

Role of Fatty Acid Desaturases and DHAP Reductase in Systemic Acquired Resistance Systemic acquired resistance (SAR) is an inducible defense mechanism in plants to confer resistance to a broad spectrum of pathogens [59, 60]. SAR is constitutively expressed in the A. thaliana SSI2 mutant. Moreover, the SSI2 gene encodes a stearoyl carrier protein desaturase that catalyzes the conversion of acyl carrier protein-conjugated stearic acid to oleic acid in the plastids [61]. The resulted oleoyl moiety of acyl carrier protein is subsequently transferred to the... 

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