Fig 4. Leaf-disc dehydration tolerance assay.

Dehydration rate in leaf discs of control (NT and PC) and CsNF-YA5-overexpressing transgenic (NF12, NF15, NF16, NF20, NF22) lines for 210 min at room temperature (A). Measurement by fresh weight reduction were carried out every 30 min. Regression lines were fitted to the data using least-squares regression analysis. Each point represents the mean of three plant replicates per treatment, with five leaf discs per replication. In situ detection of H₂O₂ in tobacco leaf discs treated with DAB (B). Representative photographs showing staining of H₂O₂ in leaf disks of WT and transgenic lines with empty vector (PC) or overexpressing CsNF-YA5 (NF12, NF15, NF16, NF20, NF22) after 180 min dehydration. WT leaf discs before dehydration (WT+H₂O₂) and treated with H₂O₂ [WT(dehydrated)+H₂O₂] or only water (WT+H₂O), after 180 min dehydration, were used as controls.