Systemic acquired resistance plant protection

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]. 

Acquired resistance is important in chemotherapy with antibiotics, where it causes serious difficulties. In plant protection with systemic active substances difficulties are also caused by acquired resistance through the appearance and... 

Resistance of microbial cells.The individual sensitivity and resistance of microbes to microbicides, which depend on the composition and structure of the outer eell layers, are termed intrinsie resistance in contradistinction to acquired resistance, which is a consequence of the seleetion pressure exerted on a microbe population in the presenee of mierobicides. The appearanee of resistant strains within a microbe population that was initially sensitive to an applied microbicide is a eonsequence of mutations and selection of the resistant mutants. Acquired resistanee is important in chemotherapy with antibioties, where it causes serious difficulties. In plant protection with systemic active substances diffieulties are also eaused by acquired resistanee through the appearance and seleetion of strains resistant to the applied microbieide concentrations whieh are limited by the plant s system. In ehemotherapy with antibiotics it is the system of humans or animals whieh limits the concentrations of active ingredients. As eorresponding limitations of microbieide concentrations in material and process protection are not generally neeessary, aequired resistance has minor importance here. Quite opposite is true of intrinsic resistance this must be taken into account whenever mierobicides are used for material protection. 

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