Emerging role of nitric oxide in combating abiotic stresses in crops

According to the current world scenario of climate fluctuations alongside continuous anthropogenic activities, the crops are confronting gigantic misfortune worldwide and that is at last influencing food security. From seedling to senescence, a plant is subjected to abundant stressful events. Each one of these progressions contributes toward several types of abiotic stresses in crops that modify their normal physiological and biochemical processes. One common response of crops is nitric oxide (NO) production under such stressful environments. NO is a small gaseous, uncharged, biological second messenger that can interact freely with different targets and bring about the growth and development of crops. NO is considered a key stress alleviator that has the ability to strengthen the defense system of plants in combating abiotic stresses. NO helps in mitigating diverse abiotic stresses like drought, salinity, temperature, heavy metals, and UV-B in various crop plants by modulating several physiological, and biochemical processes, triggering several stress-responsive genes, post-translational modifications (PTMs), and overall growth in plants. NO is involved in the cross-talk with various plant growth regulators to initiate stress signaling and bring out the best stress-related responses to tackle the stressful environment. However, several research gaps still exist regarding the exact mechanism of signaling, how its levels increase rapidly, and its ubiquitous nature, yet to be explored to develop resilient varieties that can withstand stresses and at last feed the entire world. This multifaceted molecule is grabbing all the attention of the scientific community to use its potential to develop stress-tolerant crops that are needed to fulfill the requirements and preferences of all the generations to come.