Striking a balance:does nitrate uptake and metabolism regulate both NO generation and scavenging?

Nitric oxide (NO) influences many aspects of plant development and responses to stress.The concentration of NO can play an important role in influencing its action (for example, in stomatal regulation; Wilson et al., 2009) so that the mechanisms through which NO content is modulated must be an important facet of NO research. Whilst NO generation mechanisms are clearly important, NO removal is of equal relevance, especially as plants will be continually exposed to NOx (NO + NO2) gases derived from soil microbial activity (Mur et al., 2013). Establishing and regulating a poise between NO generation, NO fumigation from external sources and NO scavenging, which also needs to be flexible enough to change in response to a variety of physiological cues, is an under-considered aspect of plant NO biology.