Interaction between hydrogen peroxide and plant hormones during germination and the early growth of pea seedlings

Abstract

Hydrogen peroxide (H2O2) increased the germination percentage of pea seeds, as well as the growth of seedlings in a concentration-dependent manner. The effect of H2O2 on seedling growth was removed by incubation with 10 μ m ABA. The H2O2-pretreatment produced an increase in ascorbate peroxidase (APX), peroxidase (POX) and ascorbate oxidase (AAO). The increases in these ascorbate-oxidizing enzymes correlated with the increase in the growth of the pea seedlings as well as with the decrease in the redox state of ascorbate. Moreover, the increase in APX activity was due to increases in the transcript levels of cytosolic and stromal APX (cytAPX, stAPX).The proteomic analysis showed that H2O2 induced proteins related to plant signalling and development, cell elongation and division, and cell cycle control.A strong correlation between the effect of H2O2 on plant growth and the decreases in ABA and zeatin riboside (ZR) was observed.The results suggest an interaction among the redox state and plant hormones, orchestrated by H2O2, in the induction of proteins related to plant signalling and development during the early growth of pea seedlings. © 2010 Blackwell Publishing Ltd.