detection of salicylic acid in sunflower seedlings under salt stress.

Salicylic acid (SA) is an important phytohormone. It plays an essential role in regulating many physiological processes of plants. Most of the conventional methods for SA detection are based on processes. More attention should be paid to develop methods for SA detection. In this work, Pt nanoflowers and GO were simultaneously electrodeposited and reduced on a Pt wire microelectrode in one step. The Pt nanoflowers/ERGO modified Pt microsensor demonstrated high sensitivity and selectivity for SA. SA could be detected from 100 pM to 1 μM with a detection limit of 48.11 pM. Then this microsensor was used to detect SA in the stem of sunflower seedlings under different salt stresses . The result showed that with the increasing concentration of salt, SA levels decreased. Our result was also confirmed by UPLC-MS and gene expression analysis. To the best of our knowledge, this is the first report of detection of SA in plants using the Pt nanoflowers/ERGO modified Pt microelectrode. It is foreseeable that our strategy could pave the way for the detection of phytohormones in plants.