Emerging roles for ROS and RNS - versatile molecules in plants

Increased cellular levels of potentially harmful reactive oxygen species (ROS) and reactive nitrogen species (RNS) come about as plants contend with harsh environmental conditions. At low concentrations, however, ROS and RNS can act as signals for the regulation of growth and development and for defence against biotic and abiotic stress. Indeed, we now know that they are involved in nearly every facet of plant metabolism and cell function. This virtual issue introduces active research in this rapidly moving field, as well as discussing the gaps in our knowledge and the technical developments which are opening up new vistas.