Micronutrient manipulation can enhance crop resilience against pathogens, but the mechanisms are mostly unknown. We tested whether priming Capsicum annuum plants with zinc (5 μM Zn) or manganese (3 μM Mn) for six weeks increases their immunity against the generalist necrotroph Botrytis cinerea compared to deficient (0.1 μM Zn, 0.02 μM Mn) and control conditions (1 μM Zn, 0.6 μM Mn). Zinc priming reduced the pathogen biomass and lesion area and preserved CO2 assimilation and stomatal conductance. Zinc mobilization at the infection site, visualized by micro-X-ray fluorescence, was accompanied by increased Zn protein binding obtained by size exclusion HPLC-ICP/MS. A common metabolic response to fungal infection in Zn- and Mn-primed plants was an accumulation of corchorifatty acid F, a signaling compound, and the antifungal compound acetophenone. In vitro tests showed that the binding of Zn2+ increased, while Mn2+ binding decreased acetophenone toxicity against B. cinerea at concentrations far below the toxicity thresholds of both metals in unbound (aquo complex) form. The metal-specific response to fungal infection included the accumulation of phenolics and amino acids (Mn), and the ligand isocitrate (Zn). The results highlight the importance of Zn for pepper immunity through direct involvement in immunity-related proteins and low molecular weight Zn-complexes, while Mn priming was inefficient.

Czech Academy of Sciences Biology Centre Institute of Plant Molecular Biology Laboratory of Plant Biophysics and Biochemistry Branišovská 31 1160 České Budějovice 370 05 Czech Republic

Czech Academy of Sciences Biology Centre Institute of Plant Molecular Biology Laboratory of Plant Biophysics and Biochemistry Branišovská 31 1160 České Budějovice 370 05 Czech Republic; University of South Bohemia Faculty of Science Branišovská 31 1160 České Budějovice 370 05 Czech Republic

Czech Academy of Sciences Biology Centre Institute of Plant Molecular Biology Laboratory of Plant Virology Branišovská 31 1160 České Budějovice 370 05 Czech Republic

University of South Bohemia Faculty of Science Branišovská 31 1160 České Budějovice 370 05 Czech Republic

Citace poskytuje Crossref.org

How eriophyid mites shape metal metabolism in leaf galls on Tilia cordata