## 1 Introduction  
Seed germination is the most crucial stage for crop establishment, especially under soil-related stresses such as salinity, drought, nutrient deficiency, heavy metals, etc. Amongst these, soil salinity is one of the major abiotic stresses which is detrimental in achieving a uniform and healthy crop stand in many crop plants [1; 2]. It hampers the overall plant growth by delaying seed germination and reducing germination rate, to finally retard the optimum growth of seedlings [3]. Salt stress causes several physiological and biochemical abnormalities such as ionic toxicity, osmotic imbalance and mineral deficiency due to high Na\({}^{+}\) influx [4]. The menace of soil salinity is getting worse with time, and if left unchecked will turn 50% of the world's arable land into salt-affected soils by 2050 [2; 3].In addition to restricting salinization and investing in reclamation of degraded saline soils, seed/plant-based approaches must be adopted for integrated management of the impending crisis. Soybean (_Glycine max_ (L.[PERSON] [PERSON]) is an economically important legume crop cultivated around the world, principally for vegetable oil and protein feed for humans as well as livestock [5]. However, the germination of soybean and its overall performance is severely affected by salt stress [3; 6]. Hence, it becomes pertinent to examine the potential of seed enhancement techniques in lowering the risk involved in achieving a reasonably good plant population under the stressed environment. Seed priming is a technique to stimulate seed metabolic processes during germination and improve their performance under diverse environmental conditions [7; 8]. Magnetopriming is a non-invasive dry seed priming treatment that has been widely used to enhance seedling vigor and plant growth under various environmental cues [9; 10; 11; 12; 13]. It can improve seedling growth under various abiotic stresses (drought, salt, heavy metal toxicity and UV-B stress) via increased metabolic processes like \(\alpha\)-amylase, protease, nitrate reductase and nitric oxide synthase-like activities during germination [9; 12; 14; 15; 16]. The biological effects of magnetopriming may be explained as an interaction of magnetic field and ionic current in the plant embryo cell membrane that leads to changes in both ionic concentrations and osmotic pressure on both sides of the membrane [17]. Changes in water uptake mechanisms are caused by alterations in the ionic fluxes across the cell membrane [18]. During seed germination, the faster imbibition in magnetoprimed seeds lead to early hydration of macromolecules and higher activities of enzymes such as \(\alpha\)-amylase and nitrate reductase that are responsible for faster germination of magnetoprimed seeds [15; 16]. Nitric oxide (NO) and reactive oxygen species (ROS) are the apparent signalling molecules that play a crucial role in regulating seed dormancy and germination [9; 12; 13; 14; 15]. Apart from various reports on ROS, evidence on NO-based regulation of seed germination, photosynthesis, flowering, senescence, stomatal movement, stress tolerance, ROS scavenging and defence mechanisms in different crop species is also accumulating [16; 19; 20; 21; 22; 23; 24; 25]. However, it still remains an intriguing subject for the scientific community, as both NO and ROS serve as secondary messengers to regulate several biological processes. In our recent studies, we also provided evidence on the involvement of NO in conferring stress tolerance, through its production in nitrate reductase and nitric oxide synthase-like catalysed reactions in magnetoprimed soybean seeds under salt and UV-B stress [15; 16; 26]. The signalling role of NO and ROS is coordinated through a network of hormones that regulate the germination process. Gibberell acid (GA) and abscisic acid (ABA) have been unequivocally established in breaking seed dormancy and promoting seed germination by their antagonistic action [27; 28; 29].