Application of Mg-28 for characterization of Mg uptake in rice seedling under different pH conditions

作者：Kobayashi N I; Iwata N; Saito T; Suzuki H; Iwata R; Tanoi K^*; Nakanishi T M

来源：Journal of Radioanalytical and Nuclear Chemistry, 2013, 296(1): 531-534.

DOI：10.1007/s10967-012-2010-9

• Magnesium uptake
• Rice
• pH
• Imaging plate
• Mg-28
• Tracer experiment

The magnesium (Mg) uptake of rice seedlings treated with different pH solutions was investigated using tracer of Mg-28. The application of Mg-28 enabled the determination of Mg uptake amount within 15 min of the different pH treatments. The uptake amount of Mg-28 and its distribution in rice plants were determined by using the imaging plate. The result demonstrated that the Mg uptake amount was approximately 3 mu mol/15 min per plant in 0.27 mM Mg solution at pH 5.6, and this uptake decreased by 30 % at lower pH conditions (pH 4.5). On the contrary, the pH 6.5 condition induced the Mg uptake activity to 4.4 mu mol/15 min. The inverse relationship found between proton concentration in nutrient solution and the Mg uptake amount within 15 min of treatment demonstrated that the low pH condition could inhibit the Mg uptake activity as a consequence of the competition between Mg2+ and proton. It is concluded that under low pH conditions, regardless of other factors, there is a decrease of Mg uptake activity in rice roots.

• 出版日期2013-4