3.5.5. Changes in Endogenous JA

The JA content exhibited a trend of increasing before decreasing (Figure 4E). In the initiation period, the JA content in the treatment groups was higher than that in the control group, and increased with time reaching a peak value (126.5 ng·g<sup>−</sup>1) during callus formation, followed by decrease. As indicated by analysis, the accumulation of JA in the early stage was beneficial to callus formation, while a low level of JA in the later stage was conducive to adventitious root formation and elongation.
