Agrobacterium-mediated genetic transformation of chia (Salvia hispanica L.), a rich source of omega-3 fatty acid.

Chia (Salvia hispanica L.), a nutritionally valuable crop, is the richest source of α-linolenic acid, a key omega-3 fatty acid. Despite its nutritional benefits, a stable genetic transformation method for chia is not available. This study presents a sonication-assisted Agrobacterium-mediated transformation protocol optimized for high-efficiency transformation of chia seedlings. Key parameters including bacterial cell density, acetosyringone concentration, sonication duration, vacuum infiltration, and infection time were optimized. Results demonstrated that an optical density at 600 nm (OD₆₀₀) of 0.5, acetosyringone concentration of 100 µM, 20 min of sonication, 10 min of vacuum infiltration, and 60 min of infection significantly enhanced transformation efficiency and GUS expression. This optimized protocol was validated through Polymerase Chain Reaction and β-glucuronidase (GUS) assay in transformed plants. Our findings establish a robust and reliable transformation protocol, paving the way for future genetic engineering efforts aimed at enhancing the nutritional and agronomic traits of chia.