Fig.1

The level of intracellular ROS under different treatmentsa-e.Representative pictures of ROS levels in tobacco cells with different concentrations of CTS treatment after H2DCFDA staining(a.CK;b.5 μg·mL-1 CTS;c.10 μg·mL-1CTS;d.15 μg·mL-1CTS;e.20 μg·mL-1CTS);f-j.Representative pictures of ROS levels in tobacco cells with different concentrations of exogenous ATP treatment after H2DCFDA staining(f.CK;g.10 μmol·L-1 ATP;h.20 μmol·L-1 ATP;i.30 μmol·L-1 ATP;j.40 μmol·L-1 ATP);k-n.Representative pictures of ROS levels in tobacco cells with different treatments after H2DCFDA staining(k.CK;l. 20 μmol·L-1ATP; m.10 μg·mL-1CTS;n.10 μg·mL-1CTS+20 μmol·L-1ATP)

Fig.2

The ROS levels in tobacco cells with different con-centrations of chitosan (CTS) treatmentImage J software was used to analyze the ROS fluorescence intensity.Each value represents the mean±SD of three independent experiments.The values in the control were set into 1.0 to facilitate the comparison among the different treatments. Different letters indicate significant differences among treatments at the 0.05 level；The same as below

Fig.3

Changes of PAL activity in tobacco cells under different concentrations of CTS treatmentDetermination of PAL activity by ultraviolet spectrophotometry. Each value represents the mean±SD of six samples. Different letters indicate significant differences among treatments at the 0.05 level；The same as below

Fig.4

The ROS levels in tobacco cells with different concentrations of exogenous ATP treatment

Fig.5

Changes of PAL activity in tobacco cells under different concentrations of exogenous ATP trea-tment

Fig.6

The changes of the level of eATPcontenttreated with different CTS concentrations

Fig.7

The changes of the level of intracellular ROS under different treatments

Fig.8

Changes in cell PAL activity under different trea-tments