Expression profile of the glutathione-S-transferase gene family in response to Cu(OH)2 nanopesticide in maize

Glutathione S-transferases (GSTs) are multifunctional enzymes playing crucial roles in plant detoxification and oxidative stress responses. Copper hydroxide nanopesticides [Cu(OH)₂ NPs, 1–200 nm] are increasingly used in agriculture due to their broad-spectrum activity, but their molecular impacts on crops remain insufficiently understood. In this study, maize (Zea mays L.) seedlings received Cu(OH)₂ NPs, and their physiological, biochemical, and transcriptional responses were assessed relative to copper sulfate (CuSO₄). Exposure to both copper formulations inhibited growth, increased copper accumulation, and altered antioxidant profiles. Comprehensive expression profiling of the GST gene family revealed substantial modulation in shoots and roots, indicating an active detoxification response. These findings provide novel insight into the molecular mechanisms underlying maize adaptation to copper-based nanopesticides and contribute to knowledge required for safer, more sustainable nanomaterial use in agriculture.