Sampling Root Exudates – Mission Impossible II: Small Details Matter

The input of soluble carbon from living plant roots (i.e., root exudation) into soil has received increasing attention over recent decades, as root exudates are recognized as key drivers of plant–soil–microbe interactions. However, obtaining ecologically meaningful root exudate samples remains challenging. In this presentation, I will highlight insights into often overlooked aspects of existing exudate sampling schemes, including the effects of sampling solution volume, sampling matrix, and microbial activity. Furthermore, I will introduce a new experimental scheme that integrates established approaches for root exudate collection with rhizosphere microbiota characterization into a single, unified protocol. Fine-tuning our exudate sampling techniques is essential for advancing our understanding of the identity, fate, and function of plant metabolites released into soil and their impact on (soil) ecosystem processes.