Nano-Management Approaches for Salt Tolerance in Plants under Field and In Vitro Conditions

Soil salinity is a serious global problem that threatens a high percentage of the global soils. Salinity stress can create ionic, oxidative, and osmotic stress, along with hormonal imbalances, in stressful plants. This kind of stress was investigated on agricultural productivity at different levels, starting in vitro (plant tissue culture), through hydroponics, pots, and field conditions. Several approaches were studied for managing salinity stress, including using traditional materials (e.g., gypsum, sulfur), organic amendments (e.g., compost, biochar, chitosan), and applied manufactured or engineered nanomaterials (NMs). Application of nanomaterials for ameliorating salinity stress has gained great attention due to their high efficiency, eco-friendliness, and non-toxicity, especially biological nanomaterials. The application of NMs did not only support growing stressful plants under salinity stress but also increased the yield of crops, provided an economically feasible nutrient management approach, and was environmentally robust for sustainable crop productivity. Nano-management of salinity may involve applying traditional nano-amendments, biological nanomaterials, nano-enabled nutrients, nano-organic amendments, derived smart nanostructures, and nano-tolerant plant cultivars. Producing different plant cultivars that are tolerant to salinity can be achieved using conventional breeding and plantomics technologies. In addition to the large-scale use of nanomaterials, there is an urgent need to address and treat nanotoxicity. This study aims to contribute to this growing area of research by exploring different approaches for nano-management of current practices under salinity stress under field and in vitro conditions. This study also raises many questions regarding the expected interaction between the toxic effects of salinity and NMs under such conditions. This includes whether this interaction acts positively or negatively on the cultivated plants and soil biological activity, or what regulatory ecotoxicity tests and protocols should be used in research.