@article{c09488ea1c8142cca76b166b64b5a1c7,
title = "Soil penetration by maize roots is negatively related to ethylene-induced thickening",
abstract = "Radial expansion is a classic response of roots to a mechanical impedance that has generally been assumed to aid penetration. We analysed the response of maize nodal roots to impedance to test the hypothesis that radial expansion is not related to the ability of roots to cross a compacted soil layer. Genotypes varied in their ability to cross the compacted layer, and those with a steeper approach to the compacted layer or less radial expansion in the compacted layer were more likely to cross the layer and achieve greater depth. Root radial expansion was due to cortical cell size expansion, while cortical cell file number remained constant. Genotypes and nodal root classes that exhibited radial expansion in the compacted soil layer generally also thickened in response to exogenous ethylene in hydroponic culture, that is, radial expansion in response to ethylene was correlated with the thickening response to impedance in soil. We propose that ethylene insensitive roots, that is, those that do not thicken and can overcome impedance, have a competitive advantage under mechanically impeded conditions as they can maintain their elongation rates. We suggest that prolonged exposure to ethylene could function as a stop signal for axial root growth.",
author = "Vanhees, {Dorien J.} and Schneider, {Hannah M.} and Sidhu, {Jagdeep Singh} and Loades, {Kenneth W.} and Bengough, {A. Glyn} and Bennett, {Malcolm J.} and Pandey, {Bipin K.} and Brown, {Kathleen M.} and Mooney, {Sacha J.} and Lynch, {Jonathan P.}",
note = "Funding Information: Advanced Research Projects Agency ‐ Energy, Grant/Award Number: DE‐AR0000821; Cooperative State Research, Education, and Extension Service, Grant/Award Number: Project PEN04582; Howard G Buffett Foundation; James Hutton Institute; University of Nottingham Funding information Funding Information: The authors thank Dr Brian Atkinson and Dr Craig Sturrock from the Hounsfield Facility at the University of Nottingham for assistance with the X-ray CT study. This research was supported by the University of Nottingham, USDOE ARPA-E ROOTS Award Number DE-AR0000821, the USDA National Institute of Food and Agriculture Federal Appropriations under Project PEN04732, the Pennsylvania State University, the Howard G Buffett Foundation, and the James Hutton Institute. The James Hutton Institute receives funding from the Rural & Environment Science & Analytical Services Division of the Scottish Government. Funding Information: The authors thank Dr Brian Atkinson and Dr Craig Sturrock from the Hounsfield Facility at the University of Nottingham for assistance with the X‐ray CT study. This research was supported by the University of Nottingham, USDOE ARPA‐E ROOTS Award Number DE‐AR0000821, the USDA National Institute of Food and Agriculture Federal Appropriations under Project PEN04732, the Pennsylvania State University, the Howard G Buffett Foundation, and the James Hutton Institute. The James Hutton Institute receives funding from the Rural & Environment Science & Analytical Services Division of the Scottish Government. Publisher Copyright: {\textcopyright} 2021 The Authors. Plant, Cell & Environment published by John Wiley & Sons Ltd.",
year = "2022",
month = mar,
doi = "10.1111/pce.14175",
language = "English (US)",
volume = "45",
pages = "789--804",
journal = "Plant, Cell and Environment",
issn = "0140-7791",
publisher = "Wiley-Blackwell",
number = "3",
}