figshare
Browse
tssp_a_1381573_sm7665.pdf (56.76 kB)

Common reed absorbs K+ more selectively than rice against high Na+/K+ ratio in nutrient solution

Download (56.76 kB)
journal contribution
posted on 2017-10-11, 14:23 authored by Kyoko Higuchi, Kumiko Hara

The introduction of an active Na+ excretion system from salt-tolerant plants in salt-sensitive crop plants might necessitate enhancement of the robustness of K+ homeostasis and lead to improved plant growth under salt stress. To address this issue, we compared the acquisition and retention of K+ under excess Na+ concentrations in the common reed, which possesses excellent Na+ excretion ability, and low-Na+ excreting rice. Under excess Na+ concentrations, common reed maintained constant K+ content in all plant parts, whereas K+ content in rice decreased with increasing Na+ concentration. Preferential uptake of K+ against high Na+/K+ ratio in nutrient solution was approximately 10 times higher in common reed than in rice. The impact of excess Na+ on net K+ absorption rate of common reed was small. On the other hand, the net K+ absorption rate of rice was decreased by excess Na+ concentration. However, after the Na+ concentration in the nutrient solution was decreased from 50 to 1 mM, K+ absorption in rice recovered immediately. Thus, selectivity of K+ transporters or channels for K+ over Na+ in roots could be involved in the differences in K+ accumulation in rice and common reed.

History