The deficiency of nutrients in food crops is a major issue affecting the health of human beings, mainly in underdeveloped areas. Despite the development in the methods of food fortification, several barriers such as lack of proper regulations and smaller public-private partnerships hinder its successful implementation in society. Consequently, genetic and agronomic biofortification has been suggested as the potential techniques for fortifying the nutrients in diets. However, the time-consuming nature and restricted available diversity in the targeted crop gene pool limit the benefits of genetic biofortification. In agronomic biofortification, organic fertilizers face the problem of prolonged duration of nutrients release and lesser content of minerals; while in inorganic fertilizers, the large-sized fertilizers (greater than 100 nm) suffer from volatilization and leaching losses. The application of nanotechnology in agriculture holds enormous potential to cope with these challenges. The utility of nanomaterials for wheat biofortification gains its importance by supplying the appropriate dose of fertilizer at the appropriate time diminishing the environmental concerns and smoothening the process of nutrient uptake and absorption. Wheat is a major crop whose nano-biofortification can largely handle the issue of malnutrition and nutrients deficiency in human beings. Though several research experiments have been conducted at small levels to see the effects of nano-biofortification on wheat plants, a review article providing an overview of such studies and summarizing the benefits and outcomes of wheat nano-biofortification is still lacking. Although a number of review articles are available on the role of nanotechnology in wheat crop, these are mostly focused on the role of nanoparticles in alleviating biotic and abiotic stress conditions in wheat. None of them focused on the prospects of nanotechnology for wheat biofortification. Hence, in this review for the first time, the current advancement in the employment of different nanotechnology-based approaches for wheat biofortification has been outlined. Different strategies including the supply of nano-based macro- and micronutrients that have shown promising results for wheat improvement have been discussed in detail. Understanding several aspects related to the safe usage of nanomaterials and their future perspectives may enhance their successful utilization in terms of economy and fulfillment of nutritional requirements following wheat nano-biofortification.

The continuously changing environment has led to devastating effects on the normal growth and development of plants. This necessitates the understanding of different components that can be involved in alleviating these effects. In the last two decades, nitric oxide (NO) has been largely focused on as a molecule whose endogenous production and exogenous supply lead to several molecular and physiological changes in plants under stressed conditions. Although its role as a signaling molecule in endogenous production has been largely discussed, its function in dealing with contemporary abiotic stress conditions on exogenous supply remains comparatively less explored. There is growing evidence that NO plays a critical role in many physiological processes; however, there is debate about the exact mechanism(s) through which NO lessens abiotic stress on external supply. In this review, we discuss the studies that were focused on observing the effect of exogenous NO on different abiotic stresses including heavy metal stress, element deficiency or toxicity stress, salt stress, drought stress, ultraviolet radiation stress, waterlogging stress, and chilling stress. Though the positive effects of endogenous NO have been discussed in brief in different sections, the focus of the review is to discuss the effects of exogenous NO on plant grown under abiotic stresses. Deciphering the underlying mechanism of exogenous NO treatment may open up new ideas that can suggest the successful application of NO in agricultural regions to reduce the damaging influences of different abiotic stresses.