Priming of soybean seeds with nanoscale molybdenum as a sustainable strategy for enhancing crop resilience to drought and salt stress

Abiotic stresses are exacerbated by climate change and the overuse of agrochemicals, threatening global food security. Seed priming with molybdenum disulfide nanoflowers (MoS₂ NFs) was explored as a strategy to improve soybean resilience under stress. We hypothesize that the enzyme mimetic function of MoS2 NFs could protect seeds from stress at an early stage and trigger corresponding prolonged protective effects. Priming seeds with 100 mg/L MoS2 NFs for 24 h significantly improved germination (60% and 15%) and seed vigor (97.6% and 79.4%) under drought and salt stress compared with controls (untreated) through enhanced antioxidative response and reprogrammed proteomics. The metabolomic profile underwent significant reprogramming, characterized by distinct changes in amino acid metabolism and flavonoid synthesis pathways. These metabolic adjustments strengthening overall antioxidant capacity and abiotic stress tolerance. sp-ICP-MS analysis suggests that MoS2 NFs transform in the seeds upon seed priming, releasing a fraction of Mo (1.44%-4.17%), which becomes incorporated into plant tissues afterwards. These beneficial protective properties extend to the seedling stage, with the multifunctional action of MoS2 NFs being critical to the activity. Overall, this study demonstrates a practical and scalable seed priming strategy using MoS2 NFs to improve crop resilience under abiotic stress.