Phytoalexins are low molecular weight antimicrobial compounds that are produced by plants as a response to biotic and abiotic stresses. The rapidity and extent of their accumulation is determined by their release of immediate precursors from conjugates or de novo synthesis, as well as detoxification as a result of plant or microbial enzymes. The rapidity of phytoalexin accumulation is associated with resistance in plants to diseases caused by fungi and bacteria, although the genetic information for phytoalexin synthesis is found in susceptible and resistant plants. Phytoalexins are only one component of the complex mechanisms for disease resistance in plants. | Role of phytoalexins in plant disease resistance