Molecular basis of plant immunization

Publisher Summary The chapter discusses the molecular basis of plant immunization. There are several major areas of practical use of plant vaccinations such as the method of protection against viral diseases, prevention of tree infection by root rot causal agents, treatment of the chestnuts infected by the fungus Criphonrectria parasitica and treatment of seeds with rhizospheric bacteria. The principal ideas of studying immunization are based on the experimental data showing that the treatment of plants with attenuated strains of phytopathogenic microorganisms can induce resistance to more pathogenic strains. The section on immunization in plants explains how the chemical protection of plants has been traditionally based on the use of pesticides toxic for pathogenic organisms and how the use of fungicides has undergone three stages in its history. The first- and second-generation fungicides are nonspecific; they possess a broad range of effects on various fungi and do not damage plants. The third-generation fungicides are systemic organic products specific for particular groups of fungi and not toxic for plants. The chapter also describes the agents affecting parasite pathogenicity and the agents influencing plant resistance. Some of the ways of enhanced plant resistance against disease induced by chemical treatment are the building of a protecting film on the leaf surface; enhancement of cell wall resistance against pectolytic enzyme attack; and activation of phenol metabolism, oxidative enzymes, and phytoalexins.