Effects of salt stress on sucrose metabolism and growth in Chinese rose (Rosa chinensis)

Abstract

Salt stress is a major abiotic stress with detrimental effects on plants. Sucrose, the main product of photosynthesis in plants, is used as a source of energy for the development of Chinese rose (Rosa chinensis). Hua Xianzi, a variety of Chinese rose, was investigated in this study. Phenotypic traits such as digital biomass, greenness average, leaf angle and leaf area, as well as physiological characters such as proline (Pro), malondialdehyde (MDA), H2O2, O2- and antioxidant enzymes such as SOD (Superoxide Dismutase), POD (Peroxidase), CAT (Catalase) and APX (Ascorbate Peroxidase), changed significantly in response to salt stress (150 mmol/L NaCl for 72 h). The physiological changes were examined based on photosynthetic and fluorescence indicators. Salt stress increased the concentration of glucose, fructose and sucrose, upregulated the expression of Rc-SS1, Rc-SS2, Rc-SPS1, Rc-SPS2, Rc-αA1, Rc-αA2, Rc-αA3, Rc-βA1 and Rc-βA3 genes. Finally, it decreased the starch content in leaves. This study revealed that salt stress disrupted the equilibrium of sucrose metabolism in leaves. This finding provides the basis for further research into the mechanism of salt tolerance adaption.