4.3 Electrolyte leakage assay
To measure electrolyte leakage caused by high temperature, seedlings were harvested before or after heat triggering and rinsed twice with deionized water, placed into 10-mL tubes containing 8 mL of deionized water. Samples were placed at room temperature for 24 h and measured the conductivity using an Electro-conductivity meter (DDSJ-308A, Lei-ci, Shanghai, China), recorded as R1. Samples were then boiled at 100°C for 15 min and shaken at room temperature for another 1 h before the electrical conductivity was measured again, recorded as R2. The electrolyte leakage was calculated as: R1/R2. Three biological replicates were performed for per simple.