Background The control of bacterial diseases in plants is largely based on the use of copper salts, which are some of the few chemicals still allowed in organic agriculture. However, copper derivatives do not degrade in the environment and their tendency to accumulate in soil and water poses a serious threat to a wide range of organisms and micro-organisms, and to their ecosystems. Moreover, copper-contaminated agricultural soils have been shown to contain high proportions of antibiotic-resistant bacteria in comparison with non-contaminated soils. Therefore copper-contaminated soils should be considered a dangerous reservoir of genes for antibiotic resistance, easily transmitted to pathogenic bacteria infecting animals and humans, with a significant impact on their health. The replacement of copper with more favourable alternatives is a priority for European agricultural policy. Surprisingly, no copper-free substitutes for copper fungicides have so far been found, though some preparations appeared to have potential. This research needs to be further investigated and built on, however. Objectives The overall goal of the After-Cu project will be to demonstrate the environmentally friendly and anti-infective properties of innovative peptide molecules against plant pathogenic bacteria, with a view to substituting the peptide molecules for traditional copper compounds that are used in conventional and organic agriculture. The project will also: Demonstrate the in vitro and in vivo efficacy of anti-infective peptides as a replacement for copper compounds, through optimised field treatments on several plants (olive, kiwi fruit and citrus); and Contribute to the protection of the environment by reducing the substantial pollution that arises because of the accumulation of copper as a result of its use in plant disease management. Expected results: The project expects to achieve the following results: An 80-100% long-term reduction of copper pollution in agricultural soils thanks to their substitution with the anti-infective peptides; A 70% improvement in soil fertility as a result of from the reduction in/replacement of copper compounds; Better control of bacterial plant diseases; A 65% increase in soil microbial diversity with a positive impact on soil biology and on the transformation of nutrients; A long-term reduction of 90% in copper pollution in watercourses; An 80% reduction of the toxicological impact of copper pollution on terrestrial, aerial and aquatic fauna; A 100% reduction of copper residues in fruit and vegetables; A short-term reduction of 85% in copper and antibiotic-resistant bacteria at agricultural sites; A long-term reduction of 60% of the reservoir of environmental antibiotic-resistant bacteria and of their spread, with a subsequent reduction of the risks to human and animal health; A 20% reduction in the consumption of energy used for remediation of copper-contaminated soils; and An 80% reduction in the use of chemical additives in biotechnological synthesis of the anti-virulence peptides, in comparison with conventional chemical processes.