Unlocking nature's cold defense: Silkworm sand-derived ICE6 boosts pepper resilience through antioxidant activation...

Iron Chlorine E6 (ICE6), an innovative plant growth regulator derived from silkworm sand, has been recognized for its ability to promote plant growth and enhance resistance to various abiotic stresses across multiple crops. However, the precise mechanisms underlying ICE6's role in improving plant stress tolerance remain largely unclear. To address this gap, this study investigated the potential of ICE6 to enhance cold tolerance in pepper seedlings under low-temperature conditions. ICE6 was applied as a foliar spray, and its effects were evaluated by analyzing physiological and biochemical parameters, as well as the expression of cold-related genes.The results demonstrated that pepper seedlings pretreated with ICE6 exhibited a significantly lower cold injury index compared to the water-treated control group after 60 h of low-temperature exposure. Furthermore, ICE6 treatment led to notable increases in the levels of soluble sugars (SS), proline (Pro), superoxide dismutase (SOD), peroxidase (POD), and glutathione (GSH) in the leaves, while malondialdehyde (MDA) concentrations were reduced. Additionally, the expression levels of cold-responsive genes were significantly influenced by both low-temperature stress and ICE6 treatment. In conclusion, the exogenous application of ICE6 effectively enhances plant tolerance to cold stress by activating antioxidant enzyme activity, mitigating metabolic damage, and regulating the expression of cold-responsive genes. These findings suggest that ICE6 has the potential to play a significant role in promoting sustainable pepper productivity in low-temperature environments.