AUTHOR=Goeschl John D. , Han Lifeng TITLE=A Proposed Drought Response Equation Added to the Münch-Horwitz Theory of Phloem Transport JOURNAL=Frontiers in Plant Science VOLUME=Volume 11 - 2020 YEAR=2020 URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2020.505153 DOI=10.3389/fpls.2020.505153 ISSN=1664-462X ABSTRACT=Theoretical and experimental evidence for an effect of sieve tube turgor pressure on the mechanisms of phloem unloading near the root tips during moderate levels of drought stress is reviewed. An additional, simplified equation is proposed relating turgor pressure to the rate kinetics of membrane bound transporters. The effect of such a mechanism would be to decrease phloem transport Speed, but increase Concentration and thus prevent or delay negative pressure in the phloem.