The response of the laboratory cultivated Quercus coccifera plants to an artificial water stress

Abstract

Seedlings of Quercus coccifera were planted to grow in a series of liquid culture–mediums of gradually increasing PolyEthylene Glycol (PEG) concentration. The induced water stress strongly affected plant growth. As the PEG concertation raised the growth of the stems and roots was retarded, roots appeared to rely on the distribution of the phenolic containing cells for retaining a water flow, phenolic synthesis dramatically increased in the leaves and shifted to the production of condensed forms, oxidative stress appeared, thus, Reactive Oxygen Species (ROS) steeply increased, pigment absorption weakened and a remarkable rate of L-Dopa DeCarboxylase (DDC) expression was triggered. Phytochemical investigation via Liquid Chromatography – High Resolution Mass Spectrometry (LC-HRMS) contributed to the detailed identification of the phenolic compounds in leaf extracts, and confirmed their profiles and metabolism both via biochemical detection and anatomical distribution the microscopic findings. Totally 25 compounds were identified showing qualitative and quantitative alternations in different PEG treatments.

Keywords

• Quercus coccifera
• Mediterranean climate
• Water stress
• Secondary metabolites
• ROS
• DDC