Fig. 2.

Attenuation of JA negative feedback signaling at low temperature after mechanical wounding of C. sinensis leaves. (A) Time course of phytohormone analysis of C. sinensis leaves under different treatments. Phytohormones were analyzed by UPLC-QTOF-MS. Isotope-labeled JA, ABA, and SA were used as internal standards. Asterisks (*) indicate statistically significant differences between wounded plants incubated at 15 °C and 25 °C (Student’s t-test; P≤0.05; n.s.=not significant). All data are means of three independent experiments, and error bars represent ±SD. (B) Expression level of JA biosynthesis-related genes under different treatments. The gene expression level was analyzed by qRT-PCR and calculated using the 2^−Δct method. * indicates statistically significant differences between a wounded plant incubated at 15 °C and 25 °C (Student’s t-test; P≤0.05; n.s.=not significant). All data are means of three independent experiments, and error bars represent ±SD.