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Root lodging, the agronomic term for plant mechanical failure, causes yield loss in crops, including maize. Brace roots can provide structural support and assist in preventing root lodging. While the mechanics of brace roots (e.g., stiffness and strength) can play a role in their ability to prevent root lodging, there has been limited characterization of individual brace root mechanical properties. Methods to quantify root mechanics can thus be useful for characterizing maize mechanical traits and breeding new varieties with improved root anchorage and lodging resistance. Here, we describe a protocol for evaluating mechanical properties of maize brace roots. Specifically, we outline the steps necessary to perform three-point bend mechanical testing of maize brace roots using an Instron Universal Testing Stand. We describe root preparation, instrument setup, method establishment, testing, and data analysis. While we exemplify the protocol using maize brace roots, the approach can be adapted for assessing the mechanics of other plants or root types.
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This content will become publicly available on October 15, 2026
Experimental Approaches for Assessing Root Mechanical Properties in Maize
The mechanical properties of individual roots and entire root systems play key roles in essential root functions such as water and nutrient acquisition, defense against soil microorganisms, and plant anchorage. However, relatively few studies have quantified the mechanics (e.g., stiffness and strength) of individual and entire root systems, or explored the link between root mechanics and root functions. This limitation is likely due to a lack of standardized methods for quantifying root mechanical properties, and has created a gap in our understanding of how root mechanical traits contribute to root functions. To date, most of our knowledge comes from studies in maize, where mechanical failure (i.e., root lodging) has detrimental impacts on crop yield. Here, we review the importance of root mechanics for maize production and discuss methods used to measure individual and entire root system mechanics.
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- PAR ID:
- 10650827
- Publisher / Repository:
- Cold Spring Harbor Laboratory Press
- Date Published:
- Journal Name:
- Cold Spring Harbor Protocols
- ISSN:
- 1940-3402
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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