NITRIC OXIDE IN PLANTS: PROPERTIES, BIOSYNTHESIS AND PHYSIOLOGICAL FUNCTIONS

Abstract

Nitric oxide (NO) is an important signalling molecule with diverse physiological functions inplants. In the last years, many advances have been obtained regarding NO synthesis and its physiologicaleffects in plants. It was found to play a crucial role in plant growth and development, starting fromgermination to flowering, ripening of fruit and senescence of organs, respiratory metabolism, as well as plantresponse to abiotic and biotic stressors. However, the molecular mechanisms underlying its effects remainpoorly understood. This review discusses some aspects related to NO in plants, such as chemical properties,synthesis pathways, antioxidant action, physiological and biochemical changes that occur in plants undernormal conditions and the possible functions of NO under changing environmental conditions. The interactionof NO with plant hormones, and cross-talk with salicylic acid are also discussed. The elucidation of suchaspects represents a challenge to future studies.