Functional Identification of Gene Demonstrates That It Enhances Saline-Alkali Stress Tolerance in .

Saline-alkali stress is a significant abiotic stress that restricts plant growth globally. Basic region leucine zipper () transcription factor proteins are widely involved in plants in response to abiotic stress such as saline-alkali stress. Based on transcriptome and quantitative real-time PCR (qRT-PCR), we found that the gene could respond to saline-alkali stress. Despite this discovery, the underlying mechanism by which the transcription factor responds to saline-alkaline stress remains unexplored. To address this gap in knowledge, we successfully cloned the (MD05G1121500) gene from for heterologous expression in , facilitating the investigation of its functional role in stress response. Compared to the wild type (WT), plants demonstrated enhanced growth and a lower degree of wilting when subjected to saline-alkali stress. Furthermore, several physiological indices of the plants altered under such stress conditions. The transgenic plants (OE-5, 6, and 8), which grew normally, exhibited a higher chlorophyll content and had greater root length in comparison to the control check (CK). effectively regulated the levels of the osmoregulatory substance proline (Pro), enhanced the activities of antioxidant enzymes such as peroxidase (POD) and superoxide dismutase (SOD), and reduced the levels of malondialdehyde (MDA) and relative conductivity (REC). These actions improved the ability of plant cells in transgenic to counteract ROS, as evidenced by the decreased accumulation of O and hydrogen peroxide (HO). In summary, the gene demonstrated effectiveness in alleviating saline-alkali stress in , presenting itself as an outstanding resistance gene for apples to combat saline-alkali stress.