Two Modes of Rubidium Uptake in Sunflower Plants

摘要

The Rb⁺-uptake kinetics in K⁺-starved sunflower (Helianthus annuus) plants can be explained by the addition of two Michaelis-Menten equations. In contrast, Rb⁺ uptake can be described by a single Michaelis-Menten equation in normal-K⁺ plants. Differences in the Kms and in the Arrhenius plots of Rb⁺ uptake in the two types of plants suggest two uptake modes.