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Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - Ethylene inhibits rice root elongation in compacted soil via ABA- and auxin-mediated mechanisms
AU - Huang, Guoqiang
AU - Kilic, Azad
AU - Karady, Michal
AU - Zhang, Jiao
AU - Mehra, Poonam
AU - Song, Xiaoyun
AU - Sturrock, Craig J
AU - Zhu, Wanwan
AU - Qin, Hua
AU - Hartman, Sjon
AU - Schneider, Hannah M
AU - Bhosale, Rahul
AU - Dodd, Ian C
AU - Sharp, Robert E
AU - Huang, Rongfeng
AU - Mooney, Sacha J
AU - Liang, Wanqi
AU - Bennett, Malcolm J
AU - Zhang, Dabing
AU - Pandey, Bipin K
PY - 2022/7/26
Y1 - 2022/7/26
N2 - Soil compaction represents a major agronomic challenge, inhibiting root elongation and impacting crop yields. Roots use ethylene to sense soil compaction as the restricted air space causes this gaseous signal to accumulate around root tips. Ethylene inhibits root elongation and promotes radial expansion in compacted soil, but its mechanistic basis remains unclear. Here, we report that ethylene promotes abscisic acid (ABA) biosynthesis and cortical cell radial expansion. Rice mutants of ABA biosynthetic genes had attenuated cortical cell radial expansion in compacted soil, leading to better penetration. Soil compaction-induced ethylene also up-regulates the auxin biosynthesis gene OsYUC8. Mutants lacking OsYUC8 are better able to penetrate compacted soil. The auxin influx transporter OsAUX1 is also required to mobilize auxin from the root tip to the elongation zone during a root compaction response. Moreover, osaux1 mutants penetrate compacted soil better than the wild-type roots and do not exhibit cortical cell radial expansion. We conclude that ethylene uses auxin and ABA as downstream signals to modify rice root cell elongation and radial expansion, causing root tips to swell and reducing their ability to penetrate compacted soil.
AB - Soil compaction represents a major agronomic challenge, inhibiting root elongation and impacting crop yields. Roots use ethylene to sense soil compaction as the restricted air space causes this gaseous signal to accumulate around root tips. Ethylene inhibits root elongation and promotes radial expansion in compacted soil, but its mechanistic basis remains unclear. Here, we report that ethylene promotes abscisic acid (ABA) biosynthesis and cortical cell radial expansion. Rice mutants of ABA biosynthetic genes had attenuated cortical cell radial expansion in compacted soil, leading to better penetration. Soil compaction-induced ethylene also up-regulates the auxin biosynthesis gene OsYUC8. Mutants lacking OsYUC8 are better able to penetrate compacted soil. The auxin influx transporter OsAUX1 is also required to mobilize auxin from the root tip to the elongation zone during a root compaction response. Moreover, osaux1 mutants penetrate compacted soil better than the wild-type roots and do not exhibit cortical cell radial expansion. We conclude that ethylene uses auxin and ABA as downstream signals to modify rice root cell elongation and radial expansion, causing root tips to swell and reducing their ability to penetrate compacted soil.
KW - Mutation
KW - auxin
KW - roots
KW - Indoleacetic Acids - metabolism
KW - Plant Roots - growth & development - metabolism
KW - Oryza - genetics - growth & development - metabolism
KW - Ethylenes - metabolism
KW - Mixed Function Oxygenases - genetics - metabolism
KW - ethylene
KW - Abscisic Acid - metabolism
KW - Soil
KW - soil compaction
KW - ABA
KW - Plant Proteins - genetics - metabolism
U2 - 10.1073/pnas.2201072119
DO - 10.1073/pnas.2201072119
M3 - Journal article
C2 - 35858424
VL - 119
SP - e2201072119
JO - Proceedings of the National Academy of Sciences of the United States of America
JF - Proceedings of the National Academy of Sciences of the United States of America
SN - 0027-8424
IS - 30
M1 - e2201072119
ER -