不同浓度钠对甜菜生长及生理特性的影响

采用1/2 Hoagland 营养液室内培养试验，研究不同浓度Na+ 对甜菜幼苗生理生化指标和营养元素吸收的影响。结果表明，0.759 mmol/L Na+可提高甜菜幼苗体内Na+ 含量和幼苗高度，增加叶面积（除了9 mmol/L Na+）和干物质量，降低叶片水势，提高叶片的相对含水量、 GPX和CAT的活性，促进甜菜幼苗叶片的吸水及保水能力。3 mmol/L Na+对甜菜幼苗的生长促进作用最明显，可提高CAT、 GPX活性并维持较高的SOD活性，降低MDA含量和相对电导率，未明显降低甜菜体内N、 P和K含量，是甜菜幼苗生长的最佳Na+浓度。

Effects of different Na+ concentration on the growth and physiological traits of sugar beet

Sugar beet was cultivated in the hydroponic experiment to investigate the effects of the different Na⁺ concentrations on plant growth, physiological and biochemical character and nutrient absorption of sugar beet seedlings. The results show that the height, dry weigh of sugar beet seedlings, and leaf area (except 9 mmol/L), relative water content, activities of GPX and CAT of leaves increased, while water potential of leaves decreased when the Na⁺ concentrations were 0.75-9 mmol/L. Na+ promoted capacity of water absorption and preserving of sugar beet seedling. Relative water content of leaf raised, water potential of leaves, MDA content of leaves and electrolyte conductivity of leaves reduced, activity of SOD remained unchanged, activities of GPX and CAT were promoted, absorbed dose of nutrient elements of N, P, K were unchanged when the concentration of Na⁺ was 3 mmol/L. 3 mmol/L Na⁺ in the 1/2 Hoagland nutrient solution was best to stimulate the growth of sugar beet seedlings.