Guangdong nongye kexue (Jun 2023)
Effects of Rhizosphere NaCl Concentration on Morphology and Physiology of Mesembryanthemum crystallinum L.
Abstract
【Objective】This study aimed to investigate the effects of rhizospheric NaCl concentration on the morphology and physiology of Mesembryanthemum crystallinum L. and determine the suitable NaCl concentration for it's hydroponic cultivation in plant factories, providing references for production management.【Method】Crystal M. crystallinum L. seeds were used as material, and the Japanese garden general formula was selected for cultivation in nutrient solution under artificial light. With no NaCl added as the control (CK), NaCl was added to the final concentration of 3 g/L (T1), 6 g/L (T2), 9 g/L (T3), 12 g/L (T4), respectively. After 21 days of NaCl treatment, the morphological and physiological indicators were analyzed, and the proportion of epidermal salt vacuole area and the number of epidermal salt vacuoles were counted, so as to analyze the relationship between NaCl concentration and the morphology and physiology of M. crystallinum L..【Result】From the perspective of morphological indicators and biomass, there were no significant differences in plant height, stem thickness, leaf area, root fresh weight and shoot fresh weight compared to the CK when M. crystallinum L. was grown in a nutrient solution with a NaCl concentration of 3 g/L. In the nutrient solution with a NaCl concentration of 6 g/L, M. crystallinum L. showed significantly increased in plant height, root fresh weight and shoot fresh weight compared to the CK, indicating a certain promotion effect on the growth of M. crystallinum L.. However, in the nutrient solutions with NaCl concentrations of 9 g/L and 12 g/L, M. crystallinum L. exhibited a decreasing trend in plant height, stem thickness, leaf area, and shoot fresh weight with significant differences compared to the CK. This suggests that the growth of M. crystallinum L. is inhibited in nutrient solutions with NaCl concentrations of 9 g/L and 12 g/L. In terms of physiological indicators, the protein content, soluble sugar content, and chlorophyll SPAD value of M. crystallinum L. increased with increasing NaCl concentration, reaching the highest levels in the nutrient solution with a NaCl concentration of 12 g/L, with increases of 50.2%, 119.5%, and 77.9% compared to the CK, respectively. Regarding the epidermal salt vacuole indicators, both the proportion of epidermal salt vacuole area and the number of epidermal salt vacuoles increased with increasing NaCl concentration, reaching the maximum values in the nutrient solution with a NaCl concentration of 12 g/L, with increases of 54.9% and 182.1% compared to the CK, respectively.【Conclusion】The optimal NaCl concentration for hydroponic cultivation of M. crystallinum L. in plant factories falls within the range of 3-6 g/L.
Keywords
