Nitrogen dioxide is a positive regulator of plant growth

Abstract

Atmospheric nitric oxide (NO) and nitrogen dioxide (NO2) have long been recognized as either detrimental or beneficial for plant development. Recent research has established that NO is a phytohormone. Our present knowledge of the physiological role of NO2 is incomplete. We do know, however, that exogenous NO2 positively regulates the vegetative and reproductive growth of plants. We may therefore postulate that NO2 is a positive growth regulator for plants. We are now in a position to coherently summarize what is known of NO2 physiology; collated information on the topic is presented here. © 2014 Landes Bioscience.