Juan Alonso Serra
Center of Excellence in Tree Biology, Faculty of Biological and Environmental Sciences University of Helsinki, Finland
Title: On growth and flow: hydraulic control of above ground meristems
Host: Ove Nilsson
Mingyuan Zhu
Postdoc Associate, Benfey Lab, Duke University, Durham, USA
Title: Single-cell insights into root adaptation to soil compaction
Host: Stéphanie Robert
Soil compaction represents a major challenge to modern agriculture. One major problem caused by soil compaction is that it exerts water stress on roots as moisture release is reduced from the smaller soil pores. Despite its agronomic importance, how roots respond to compacted soil conditions at the cellular level remains unclear. Here, we pioneered the use of single-cell and spatial transcriptomics on rice roots grown in soils to delve into the cell-level mechanisms governing root responses to soil compaction. Through differential expression analysis comparing non-compacted and compacted soil-based single-cell transcriptomic data, we identified a significant up-regulation in the expression of genes responsible for water impermeable barrier formation in the outer root tissues (Exodermis). This gene up-regulation was induced by an enhanced biosynthesis of plant hormone, abscisic acid (ABA) and its release from the inner tissues (Phloem). The role of ABA in responses to soil compaction was further highlighted by the suppression of barrier formation in the exodermis in ABA-deficient rice mutants. In summary, our single cell resolution study revealed how root tissues coordinate to facilitate the retention of water in root tips during soil compaction stress.