How does the diurnal biological clock influence electrokinetics in a living plant?

This article focuses on the relationship between circadian rhythms and electrokinetic phenomena, specifically streaming potential, in plant tissues. Experimental studies on water hyacinth (Eichhornia crassipes) and excised stems of Dracaena sanderiana demonstrate that streaming potential varies cyclically in synchronization with the plants' diurnal biological clock, influenced by factors such as sap flow rate, ionic strength, ion species, and pH of the electrolytic solutions. The findings reveal that lower ionic strength, monovalent cations, and higher pH levels increase streaming potential, reflecting changes in ion migration and hydraulic conductance regulated by circadian-controlled processes like stomatal opening and aquaporin activity. These results provide quantitative insights into how electrokinetics in plant vascular systems are modulated by internal biological clocks, contributing to a deeper understanding of plant hydraulics and physiology.