PDJ is a kind of highly bioactive jasmonic acid derivatives synthesized artificially, which belongs to a new phytohormone group. The structure of PDJ is similar to that of jasmonic acid (JA), a natural plant growth regulator ubiquitous in vascular plants, and it has the same function and similar mode of action. Compared with JA and JA. Me, PDJ has the characteristics of good chemical stability, low volatility and longer duration of physiological effects. At low concentrations, PDJ has stronger promotion than JA, and is considered to be a more practical jasmonic acid compound.