Engineered nanomaterials interfaced with plant seeds can improve stress tolerance during the vulnerable seedling stage. Herein, we investigated how priming seeds with antioxidant poly(acrylic acid)-coated cerium oxide nanoparticles (PNC) impacts cotton (Gossypium hirsutum L.) seedling morphological, physiological, biochemical, and transcriptomic traits under salinity stress. Seeds primed with 500 mg L⁻¹ PNC in water (24 h) and germinated under salinity stress (200 mM NaCl) retained nanoparticles in the seed coat inner tegmen, cotyledon, and root apical meristem. Seed priming with PNC significantly (P < 0.05) increased seedling root length (56%), fresh weight (41%), and dry weight (38%), modified root anatomical structure, and increased root vitality (114%) under salt stress compared with controls (water). PNC seed priming led to a decrease in reactive oxygen species (ROS) accumulation in seedling roots (46%) and alleviated root morphological and physiological changes induced by salinity stress. Roots from exposed seeds exhibited similar Na content, significantly decreased K (6%), greater Ca (22%) and Mg content (60%) compared to controls. A total of 4779 root transcripts were differentially expressed by PNC seed priming alone relative to controls with no nanoparticles under non-saline conditions. Under salinity stress, differentially expressed genes (DEGs) in PNC seed priming treatments relative to non-nanoparticle controls were associated with ROS pathways (13) and ion homeostasis (10), indicating that ROS and conserved Ca²⁺ plant signaling pathways likely play pivotal roles in PNC-induced improvement of salinity tolerance. These results provide potential unifying molecular mechanisms of nanoparticle-seed priming enhancement of plant salinity tolerance.

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新兴研究者系列：氧化铈纳米粒子种子引发提高植物盐分胁迫耐受性的分子机制

与植物种子接触的工程纳米材料可以改善脆弱幼苗期的胁迫耐受性。本文中，我们研究了在盐分胁迫下用抗氧化剂聚（丙烯酸）包被的氧化铈纳米粒子（PNC）引发种子如何影响棉花（棉（Gossypium hirsutum L.））幼苗的形态，生理，生化和转录组性状。种子在水中用500 mg L ^-1 PNC灌注（24小时）并在盐度胁迫下（200 mM NaCl）发芽，将纳米颗粒保留在种皮内子叶，子叶和根尖分生组织中。用PNC显着启动种子（P与对照（水）相比，<0.05）增加了盐胁迫下幼苗的根长（56％），鲜重（41％）和干重（38％），改良的根部解剖结构以及增加的根系活力（114％）。PNC种子引发可减少幼苗根系中活性氧（ROS）的积累（46％），并减轻盐分胁迫引起的根系形态和生理变化。与对照相比，暴露种子的根表现出相似的Na含量，显着降低了K（6％），更大的Ca（22％）和Mg含量（60％）。相对于在无盐条件下没有纳米颗粒的对照，仅通过PNC种子引发就总共表达了4779个根转录物。在盐分压力下，²⁺植物信号通路可能在PNC诱导的盐度耐受性改善中起关键作用。这些结果提供了潜在的统一分子机制的纳米粒子种子引发植物耐盐性。