# Simulated drought with Polyethylene-Glycol (PEG) decreases above-ground performance and increases nodulation in the legume Medicago lupulina

## TL;DR

This study shows that simulated drought using PEG reduces above-ground growth in Medicago lupulina but surprisingly increases nodulation with rhizobia.

## Contribution

The study reveals that PEG-induced drought may not accurately reflect natural drought effects on legume-rhizobia symbiosis.

## Key findings

- PEG treatments significantly reduced above-ground growth of Medicago lupulina.
- PEG treatments unexpectedly increased nodulation in Medicago lupulina.
- PEG may not accurately simulate drought effects on rhizobial symbiosis.

## Abstract

We investigated drought growth responses in
Medicago lupulina
using PEG to simulate drought stress. We grew
Medicago lupulina
plants inoculated with
Sinorhizobium meliloti
in Magenta boxes under randomly assigned treatments: a control, PEG applied to the bottom (PEG added to the bottom-watering container), or PEG applied from the top (PEG poured over the growth media). PEG treatments significantly reduced above-ground growth but unexpectedly increased nodulation. Our results suggest that while PEG effectively simulates drought stress on above-ground growth parameters, it may not accurately simulate drought effects on rhizobial symbiosis.