Chapter 7 - Role of nitric oxide in regulation of biotic and abiotic stresses tolerance in plants

Abstract

Nitric oxide (NO) has emerged as an endogenous gaseous signaling molecule in plants, due to its capability to initiate a series of physiological processes which is necessary for plant defense, growth, and development along with biotic and abiotic stress response. Research suggests that it is important in a variety of biological activities like seed germination, pollination, photosynthesis, growth, and development. The developing gene expressions that influence biosynthesis and activity of phytohormones are altered by NO functional cross-talk across various stress signaling pathways. NO can have a detrimental and significant impact on phytohormones; their interactions might be antagonistic or beneficial. Its effect on plant hormone control is proportional to its concentration. A free radical molecule NO performs a variety of tasks in both healthy and unhealthy environments. When created at low concentrations, NO acts as a signal molecule, but when produced at levels high enough to cause nitro-oxidative stress, it causes cellular damage. As with other free radical molecules, NO's biological effect is dependent on its cellular concentration. Current research indicates that NO plays an important role in a variety of abiotic and biotic stress, as well as its cross-talk with other plant hormones, to help regulate growth and improvement under both stresses. This chapter focused on the range of roles of NO regulatory in plants and also gives a view of NO for abiotic and biotic stress.