Localisation of hydrogen peroxide accumulation during Solanum tuberosum cv. Rywal hypersensitive response to Potato virus Y

Inoculation with PVYNTN and also PVYN Wi induced a rapid hypersensitive response during which highly localised accumulations of H2O2 was detected in plant cell walls. The most intensive accumulation was present in the bordering cell walls of necrotic mesophyll cells and the adjacent non-necrotic mesophyll cells. Intensive electron-dense deposits of cerium perhydroxide were found along ER cistrenae and chloroplast envelopes connected with PVY particles. The precipitates of hydrogen peroxide were detected in the nuclear envelope and along tracheary elements, especially when virus particles were present inside. The intensive accumulation of H2O2 at the early stages of potato-PVY interaction is consistent with its role as an antimicrobial agent and for this reason it has been regarded as a signalling molecule.