Fig. 2.

The inward current of K⁺ channel in flue-cured tobacco root cells under different potassium levels. a. The currents were recorded at the membrane potentials from − 130 to -10 mV (in 20 mV steps) with the holding potential of − 52 mV; b. The inward current of K⁺ channel with normal potassium supply; c. Current amplitude reflected by I-V curve with normal potassium supply; d. The inward current of K⁺ channel with low potassium stress; e. Current amplitude reflected by I-V curve with low potassium stress