---
OA_type: closed access
_id: '22315'
abstract:
- lang: eng
  text: Plant tropisms enable roots to navigate complex soils by responding to directional
    environmental cues. Biological decay, although central to nutrient cycling, also
    creates microbially active and potentially hostile niches. In this work, we identified
    “saprotropism,” a previously unrecognized growth response that enables roots to
    actively bend away from decaying plant-derived matter. Fungal-driven microbial
    decomposition released organic acids and formed stable pH gradients in surrounding
    soil, allowing roots to pinpoint decay without direct contact. Root epidermal
    cells sensed this acidic gradient through the root meristem growth factor peptide-receptor
    module, converting external pH asymmetry into asymmetric abscisic acid (ABA) distribution.
    ABA asymmetry drove microtubule reorganization, which was decoded into decay-avoidant
    root bending. Together, these findings establish microbial decay–derived chemical
    gradients as an instructive signal for root navigation and expand the framework
    of microbe-soil-plant communication.
acknowledgement: 'We are grateful to H. Guo and L. Liu (Department of Biology, Southern
  University of Science and Technology) for providing the rgf1/2/3, rgi1/2/3/4, tpst-1,
  and pepr1/2 lines. We thank K.-h. Liu (College of Life Science, Northwest A&F University)
  for generously providing the ABA biosensor nlsABACUS2-400n. We also thank J. Li
  and J. Chang (School of Life Sciences, Lanzhou University) for providing the ahk2-5/cre1-2,
  ahp1/2/3, arr16/arr17, and pTCSn::GFP lines. Our thanks further extend to D. Qian,
  also from the School of Life Sciences at Lanzhou University, for sharing Arabidopsis
  line pTUB6::mCherry-TUB6. We are grateful to Y. Zhao (CAS Center for Excellence
  in Molecular Plant Sciences, Chinese Academy of Sciences) for providing nced3/5,
  snrk2.2/2.3/2.6, and pyl duodecuple mutants. We also acknowledge the Teaching and
  Research Core Facility at the College of Life Sciences, Northwest A&F University,
  particularly N. Fan, for their invaluable technical assistance. We also thank Life
  Science Research Core Services (LSRCS), Northwest A&F University, for helping with
  characterization, including CLSM (X. Liu). Fundamental and Interdisciplinary Disciplines
  Breakthrough Plan of the Ministry of Education of China JYB2025XDXM706 (Y.Z.); Qin
  Chuangyuan High-level Innovation and Entrepreneurship Talent Program QCYRCXM-2022-237
  (Y.Z.); Fundamental Research Funds for the Central Universities K20200168 (Y.Z.);
  National Natural Science Foundation of China 32570375 (Y.Z.); National Natural Science
  Foundation of China 32400699 (A.Z.); European Research Council (ERC, CYNIPS) 101142681
  (J.F.); Austrian Science Fund (FWF): P 37051-B (J.F.).'
article_number: eadw6568
article_processing_charge: No
article_type: original
author:
- first_name: Zhulatai
  full_name: Bao, Zhulatai
  last_name: Bao
- first_name: Huihui
  full_name: Wang, Huihui
  last_name: Wang
- first_name: Ai
  full_name: Zhang, Ai
  last_name: Zhang
- first_name: Ruxi
  full_name: Gao, Ruxi
  last_name: Gao
- first_name: Wen
  full_name: Gu, Wen
  last_name: Gu
- first_name: Ni
  full_name: Fan, Ni
  last_name: Fan
- first_name: Jiří
  full_name: Friml, Jiří
  id: 4159519E-F248-11E8-B48F-1D18A9856A87
  last_name: Friml
  orcid: 0000-0002-8302-7596
- first_name: Yuzhou
  full_name: Zhang, Yuzhou
  last_name: Zhang
citation:
  ama: Bao Z, Wang H, Zhang A, et al. Roots navigate around decay regions by sensing
    local pH gradients. <i>Science</i>. 2026;393(6807). doi:<a href="https://doi.org/10.1126/science.adw6568">10.1126/science.adw6568</a>
  apa: Bao, Z., Wang, H., Zhang, A., Gao, R., Gu, W., Fan, N., … Zhang, Y. (2026).
    Roots navigate around decay regions by sensing local pH gradients. <i>Science</i>.
    American Association for the Advancement of Science. <a href="https://doi.org/10.1126/science.adw6568">https://doi.org/10.1126/science.adw6568</a>
  chicago: Bao, Zhulatai, Huihui Wang, Ai Zhang, Ruxi Gao, Wen Gu, Ni Fan, Jiří Friml,
    and Yuzhou Zhang. “Roots Navigate around Decay Regions by Sensing Local PH Gradients.”
    <i>Science</i>. American Association for the Advancement of Science, 2026. <a
    href="https://doi.org/10.1126/science.adw6568">https://doi.org/10.1126/science.adw6568</a>.
  ieee: Z. Bao <i>et al.</i>, “Roots navigate around decay regions by sensing local
    pH gradients,” <i>Science</i>, vol. 393, no. 6807. American Association for the
    Advancement of Science, 2026.
  ista: Bao Z, Wang H, Zhang A, Gao R, Gu W, Fan N, Friml J, Zhang Y. 2026. Roots
    navigate around decay regions by sensing local pH gradients. Science. 393(6807),
    eadw6568.
  mla: Bao, Zhulatai, et al. “Roots Navigate around Decay Regions by Sensing Local
    PH Gradients.” <i>Science</i>, vol. 393, no. 6807, eadw6568, American Association
    for the Advancement of Science, 2026, doi:<a href="https://doi.org/10.1126/science.adw6568">10.1126/science.adw6568</a>.
  short: Z. Bao, H. Wang, A. Zhang, R. Gao, W. Gu, N. Fan, J. Friml, Y. Zhang, Science
    393 (2026).
das_tickbox: '1'
dataavailabilitystatement: All data are available in the manuscript or the supplementary
  materials. The raw RNA-seq data have been deposited in the NCBI Gene Expression
  Omnibus (GEO) under accession number GSE315473. Microbiome sequencing data have
  been deposited in the Sequence Read Archive (SRA) under BioProject number PRJNA1397137.
  Materials are available upon request from the corresponding author.
date_created: 2026-07-13T14:57:10Z
date_published: 2026-07-09T00:00:00Z
date_updated: 2026-07-14T08:11:55Z
day: '09'
department:
- _id: JiFr
doi: 10.1126/science.adw6568
external_id:
  pmid:
  - '42424472'
intvolume: '       393'
issue: '6807'
language:
- iso: eng
month: '07'
oa_version: None
pmid: 1
project:
- _id: 8f347782-16d5-11f0-9cad-8c19706ee739
  grant_number: '101142681'
  name: Cyclic nucleotides as second messengers in plants
- _id: 7bcece63-9f16-11ee-852c-ae94e099eeb6
  grant_number: P37051
  name: Guanylate cyclase activity of TIR1/AFBs auxin receptors
publication: Science
publication_identifier:
  eissn:
  - 1095-9203
  issn:
  - 0036-8075
publication_status: published
publisher: American Association for the Advancement of Science
quality_controlled: '1'
researchdata_availability: yes
scopus_import: '1'
status: public
supplementarymaterial: yes
title: Roots navigate around decay regions by sensing local pH gradients
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 393
year: '2026'
...