Measuring the passive cuticular membrane permeability of potassium with a parallel artificial membrane permeability assay and the implications for foliar nutrient formulations

Qingwen He,Taha Rezai

doi:10.1186/s40538-019-0166-z

Abstract

A modified PAMPA (parallel artificial membrane permeability assay) is proposed for evaluating the passive cuticular membrane permeability of potassium in several foliar nutrient formulations. The modified PAMPA can measure the passive permeability of ionic nutrients under fully hydrated conditions through an artificial membrane designed to more closely resemble a plant cuticle, rather than the traditional phospholipid animal model. Foliar nutrient formulations, which in some cases contain a complex organic matter component, may be evaluated with the modified PAMPA in order to develop better structure activity relationships that can help guide rational formulation development. In addition, mechanistic insights may also be uncovered with the simplified system.

Highlights

These results suggest that looking more closely at the process of passive permeability of ions across the plant cuticle may reveal additional mechanistic insights that can assist rational formulation development
In this work we focus on measuring the passive cuticular membrane permeability of potassium in proprietary and commodity potassium formulations using parallel artificial membrane permeability assay (PAMPA)
Evaluating foliar nutrient formulations with PAMPA is of interest, since the assay can be used to selectively assess the passive cuticular membrane permeability of a nutrient, without other confounding effects

Summary

Introduction

These results suggest that looking more closely at the process of passive permeability of ions across the plant cuticle may reveal additional mechanistic insights that can assist rational formulation development. In order to do that, passive cuticular membrane permeability must first be uncoupled from all the other factors that influence foliar nutrient uptake through the use of a simple experimental setup. More recently PAMPA has been used to evaluate the passive membrane permeability of crop protection compounds [13], but to our knowledge has not been used previously to simulate nutrient transport across a leaf cuticle.

Results

Conclusion