*2.2. Relative Conductivity and Mass Loss*

Relative conductivity was measured as described by Li et al. [9] with some modifications. Thirty tuberous root disks (10 mm diameter and 2 mm thickness) were put in 100 mL of deionized water and shake at 150 cycles min−<sup>1</sup> for 1 h on a lab plate shaker. The solution conductivity was measured using a Model EC 215 conductivity meter (HANNA Instruments, Beijing, China). The total conductivity was obtained after each sample was boiled for 15 min and the relative electrolyte leakage was expressed as a percentage of the total conductivity. The results were calculated using the following Equation (1):

$$\text{Relative conductivity} = (\text{P}\_1/\text{P}\_0) \times 100\% \tag{1}$$

where P1 is the conductivity after vibration; P0 is the conductivity after boiling.

Ten marked tuberous roots were weighted, and the mass loss was calculated as follows Equation (2):

$$\text{Mass loss} = \left[ (\text{W}\_1 - \text{W}\_2) / \text{W}\_1 \right] \times 100\text{\%} \tag{2}$$

where W1 is the fresh mass; W2 is the mass after storage.
