Biological Functions of Nitric Oxide - Effects On Plants

Effects On Plants

Numerous important discoveries about nitric oxide function within plants starting in the 1990's have made it clear that nitric oxide is an important signaling compound in plants. It is involved in such diverse functions as regulation of defense mechanisms in plant-pathogen interaction, promotion of the plant hypersensitive response, symbiosis (for example, with organisms in nitrogen-fixing root nodules), development of lateral and adventitious roots and root hairs, and control of stomatal opening. Nitric oxide is known to be produced by cellular organelles, including mitochondria, peroxisomes, and chloroplasts. It plays a role in antioxidant and reactive oxygen species responses. Nitric oxide interactions have been found within signaling pathways of important plant hormones such as auxin and cytokinin. These recent discoveries are stimulating new research into nitric oxide's role within plants.

Atmospheric nitric oxide can enter the stomates of most vascular species, and can have effects ranging from leaf blemishing, to stunting of growth, to necrosis.