Soil salinity, one of the main abiotic risks to agricultural products, lowers agricultural yields, and as a result, the world's rising population confronts substantial food challenges. It's one of the world's most pressing abiotic issues, affecting 30% or more of irrigated land. Saline stress is caused by a number of different salt concentrations; however, NaCl is by far the most common salt in the ground. High salt stress is the reason for delay in seed germination, which may be caused by either the osmotic potential of the water or by the effects of certain toxic ions. This chapter covers seed priming and salt resistance approaches that generate biochemical, physiological, and structural processes in saline stress, and the interaction between seed priming and salt resistance. Priming with nanoparticles (NPs) needs more study to reduce the negative effects of salinity stress on a variety of crops grown in extreme conditions.
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Currently, agriculture is dealing with a number of issues, including output losses brought on by pests, the consequences of global warming, and the gradual dwindling of natural assets (Kah et al., 2019). Traditional farming methods have also contributed to environmental degradation through their reliance on the ever-present use of chemical fertilizers and pesticides (Kaivosoja et al., 2013). In order to meet the estimated 9–10 billion world population in 2050, crop productivity needs to increase by 25–70% (Scott et al., 2018). Therefore, the use of cutting-edge technology in agriculture is essential for the future of food production (A. Singh et al., 2021; Verma, Song, Joshi, Rajput, et al., 2022).
Abiotic plant stresses are the most common types of environmental challenges that plants face. Plants are subjected to significant amounts of abiotic stress in environments where salinity is the primary prevailing abiotic stressor. This causes a significant yearly crop decline and severely stunts the plant's growth and developmental processes. Salinity stress has a greater effect in the world's coastal, arid, and semi-arid regions (AbdElgawad et al., 2016). Inefficient irrigation practices, ineffective salinity reclamation techniques, and the use of marginal land for crop production are all contributing to the spread of salinity (Van Zelm et al., 2020). Over 800 million hectares, or about 6% of the world's land area, is covered by salty soils (Munns & Tester, 2008a). The FAO (2012) estimates that 60–80 million hectares of land have been impacted negatively by water-logging and related salinity (FAO WFP & IFAD, 2012). Salinity-related soil deterioration is a major issue that has had a detrimental influence on global agricultural production (Adhikary et al., 2022). Each year, more than 10 mha of agricultural soil is lost to salinity. More than half of the world's farmland will be lost by the end of the 21st century because of soil salinity (FAO WFP & IFAD, 2012). Plant growth is affected by soil salinity throughout all stages of development, though to varying degrees. High salinity may hinder seed germination, a crucial early growth stage. The most telling indicator of salt tolerance is whether or not a plant survives through the germination and emergence processes. As a result, the seedling and germination stages of development are particularly vulnerable to salt damage in the majority of crop species (Sharief, 2012). The inability of a germinating seed to absorb enough water is the underlying cause of poor germination (S. A. Ashraf et al., 2021).It is essential for plant stands to adapt to a salty environment during the early stages of growth (germination and seedling development). Salinity stress caused a delay in the germination of susceptible plant seeds (Ibrahim, 2016). Singh et al. (2022) found that slow germination of seeds and poor seedling establishment were both caused by soil salinity stress. Additionally, by restricting carbon uptake in the latter stages following stand formation, the Na+ lethal level present in leaves encourages a reduction in photosynthesis and early senility of the leaves (A. Hussain et al., 2018). Seeds germinate more slowly and have a lower success rate when exposed to high concentrations of salt (A. Singh et al., 2022). Seed germination rates and total amounts vary by variety and species at any given time. Osmotic stress or specific ion effects caused by salinity could have a negative impact on plant growth and seed germination. This triggers the closing of the plant's stomata and the intake of water and nutrients (such as potassium and calcium) as well as carbon dioxide (CO2) (Parihar et al., 2015). Reduced early crop growth rates are a direct result of soil salinity stress. In crucial metabolic activities, particular ion action (high Na+ and Cl- ions) and osmosis activity result in a water shortage condition, causing plant growth to slow down in high-salinity environments (Hasanuzzaman et al., 2019; Munns & Tester, 2008a; Rahman et al., 2015).There are two causes of plant growth suppression caused by salt stress in soil water. An osmotic effect is produced, and secondly, a salt-specific ion effect is brought about. These two saline stress effects lead to an a two-phase developmental reaction to salt (Munns, 2005; Munns & Tester, 2008b).