Functional analysis of the PcCDPK5 gene in response to allelopathic substances on p-hydroxybenzoic acid (p-HBA) stress in patchouli.

Calcium-dependent protein kinase (CDPK) is an important mediator for Ca signal recognition and transduction, playing a crucial role in plant stress response. Previous studies have shown that PcCDPK5 may be involved in the response of patchouli to p-hydroxybenzoic acid (p-HBA) stress. In this study, we further found that the subcellular localization of PcCDPK5 protein is in the cytoplasm, and its gene expression is closely related to continuous cropping (CC) and p-HBA stress. Under p-HBA stress, silencing the PcCDPK5 homologous gene in Nicotiana tabacum leads to decreased antioxidant enzyme activity and increased malondialdehyde (MDA) content, significantly accumulating reactive oxygen species (ROS) and affecting normal plant growth. On the contrary, overexpression of PcCDPK5 can effectively alleviate the damage caused by p-HBA stress to plant bodies. Through this research, the function of PcCDPK5 in response to p-HBA stress has been preliminarily analyzed, laying a theoretical foundation for alleviating CC obstacles in patchouli.