Overexpression of Increased Iron and High Salinity Stress Tolerance in .

In the life cycle of apple, it will suffer a variety of abiotic stresses, such as iron stress and salt stress. bHLH transcription factors (TFs) play an indispensable role in the response of plants to stress. In this study, a new gene named was separated from . According to the results of subcellular localization, was localized in the nucleus. Salt stress and iron stress affected the expression of in seedlings to a large extent. Due to the introduction of , the resistance of to salt, high iron and low iron was significantly enhanced. Under the environmental conditions of high iron and low iron, the overexpression of increased many physiological indexes of transgenic compared to wild type (WT), such as root length, fresh weight and iron content. The high level expression of in transformed can not only increased the content of chlorophyll and proline, as well as increasing the activities of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT); it also reduced the content of malondialdehyde (MDA), which was more obvious under high salt conditions. In addition, the relative conductivity, HO content and O content in transgenic decreased under salt stress. Meanwhile, can also regulate the expression of downstream genes associated with salt stress (, and ) and iron stress (, , , , and ). Therefore, can actively promote the adaptability of plants to the growth environment of salt and low and/or iron.