There is a cross-talk between polyamines (PAs) and phytohormones under drought and well-watered conditions.
The changes of endogenous PAs and phytohormones resulted in accelerated proline metabolism and elevated AsA–GSH cycle and relevant genes expression.
Other metabolites such as total phenols, flavonoid, cysteine and metallothionein (MT) were also elevated with significantly increased endogenous PAs content.
On the contrary, the deficiency in PAs weakened antioxidant defense and proline metabolism, inhibited MT genes expression leading to aggravation of drought-induced stress damage.