AgNPs Seeds Nanopriming Enhanced the Tolerance of Chinese Cabbage to Diverse Abiotic Stresses

Abstract

Climate change-induced diverse abiotic stresses threaten agricultural production. To address this challenge, enhancing a crop’s resilience against diverse abiotic stresses has become imperative. Here, we demonstrate that silver nanoparticles (AgNPs) with reactive oxygen species (ROS)-generating properties can serve as a seed priming agent to simultaneously enhance tolerance of Chinese cabbage (Brassica campestris L.) to diverse abiotic stresses. AgNPs priming (40 mg/L, 4 h) significantly increased ROS levels in Chinese cabbage seeds compared to hydropriming, while enhancing seed germination and seedling growth under drought (5–15% PEG-6000), salinity (50–150 mmol/L NaCl), and low-temperature (10–15 °C) stress conditions. AgNP-primed seeds exhibited significant increases in the vigor index (32.3–85.4%), shoot length (0.16–40.4%), root length (48.5–112.7%), and biomass (6.7–19.7%) relative to hydroprimed seeds. RNA sequencing analysis revealed that AgNPs priming triggered comprehensive transcriptomic reprogramming in the primed seeds. A number of signaling and defense pathways, including plant–pathogen interaction networks, MAPK-mediated stress transduction pathways, phytohormone signaling cascades, glutathione-mediated detoxification systems, and phenylpropanoid biosynthesis, were activated in AgNPs-primed seeds. Notably, this acquired resistance persisted into the vegetative stage. Four-week-old cabbage plants exhibited resistance to drought, cold, and salt. At harvest, the yield of AgNPs-primed plants increased by 10.7–19.3% compared to hydropriming under all tested adverse conditions. These results demonstrate that AgNPs seed priming approach enhances cabbage tolerance to diverse abiotic stresses without yield penalty, offering a simple strategy for cultivating climate-resilient crops.