Plant materials and growth conditions
All Arabidopsis thaliana used in this study were in the Columbia (Col-0) ecotype background and were obtained from the Arabidopsis Biological Resource Center. Homozygote mutants were identified by PCR with corresponding primers. All mutants and WT Arabidopsis were grown in an artificial climate chamber with the following growth conditions: 21–23℃, 100 μmol photons m-2s-1, 18-h light/8-h dark cycle, and 60–70% humidity. For the NF and LIN treatments, surface-sterilized mutant and WT seeds were planted on 1/2 Murashige and Skoog (1/2 MS) medium (PhytoTechnology Laboratories, LLC™, USA) containing 1% sucrose and 0.8% agar supplemented with either 5 µM NF (Sandoz Pharmaceuticals; Vienna, Austria) or 220 µg/mL LIN (Sigma; St. Louis, MO).