Influence of some new aminophosphonates on electrical properties and stability of plasma membranes of plant cells

Abstract

The effect of new aminophosphonates, synthesized for potential agricultural application, on membrane potential and electrical conductance of internodal cells of Nitellopsis obtusa and their efficiency in modifying the properties of cucumber (Cucumis sativus cv "Wisconsin") cotyledon membranes was studied. They differed in substituents at the carbon and phosphorus atoms. It was found that the organophosphorous compounds caused depolarization of the membrane resting potential and increased electrical conductance of alga membranes. They also influenced chlorophyll content and efflux of electrolytes from cucumber cotyledons. The most significant effects were observed for the compound with iso-propyl substituents at the P atom. In contrast, the weakest modifier of the studied compounds was the one having phenolic substituents at that atom. The observed changes are most probably the result of direct interaction of aminophosphonates with the lipid phase of the plasma membrane and the induced structural changes in it.