Plant immunization — manipulating innate defence responses (abstract only)
J.A. LucasCitation:Lucas J.A. (2002): Plant immunization — manipulating innate defence responses (abstract only). Plant Protect. Sci., 38: 243-243.
The discovery of systemic defence responses in plants induced by biotic and abiotic agents prompted comparisons with animal immunity. While recent molecular analyses have revealed conservation of certain defence signalling and response pathways, the specificity and expression of induced resistance differ between plants and animals. Activation of plant systemic resistance by biotic or chemical agents primes cells to respond more rapidly to subsequent pathogen attack. Expression of several classes of defence-related genes is accelerated in primed plants. This phenotypic conversion from a susceptible to more resistant state apparently occurs in the absence of specific R-gene recognition. Furthermore the enhanced resistance can be expressed against pathogens or pests unrelated to the inducer. Examples from recent work in our laboratory on legumes, brassicas and cereals will be presented. Analysis of model plant systems, notably Arabidopsis, has demonstrated the existence of both salicylate (Systemic acquired resistance SAR) and jasmonate/ethylene (induced systemic resistance ISR) dependent pathways. The mechanism of defence priming is, however, not currently known. An increasingly diverse range of agents have been reported as potential inducers of systemic resistance. This, coupled with increased understanding of the signalling networks involved, should expand the options for practical exploitation of induced resistance in integrated disease and pest management systems