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Abstract Maize stalk lodging is the structural failure of the stalk prior to harvest and is a major problem for maize (corn) producers and plant breeders. To address this problem, it is critical to understand precisely how geometric and material parameters of the maize stalk influence stalk strength. Computational models could be a powerful tool in such investigations, but current methods of creating computational models are costly, time-consuming and, most importantly, do not provide parameterized control of the maize stalk parameters. The purpose of this study was to develop and validate a parameterized 3D model of the maize stalk. The parameterized model provides independent control over all aspects of the maize stalk geometry and material properties. The model accurately captures the shape of actual maize stalks and is predictive of maize stalk stiffness and strength. The model was validated using stochastic sampling of material properties to account for uncertainty in the values and influence of mechanical tissue properties. Results indicated that buckling is influenced by material properties to a greater extent that flexural stiffness. Finally, we demonstrate that this model can be used to create an unlimited number of synthetic stalks from within the parameter space. This model will enable the future implementation of parameter sweep studies, sensitivity analysis and optimization studies, and can be used to create computational models of maize stalks with any desired combination of geometric and material properties.
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This content will become publicly available on July 13, 2026
A biphasic trajectory for maize stalk mechanics shaped by genetic, environmental, and biotic factors
SUMMARY Stalk mechanical properties impact plant stability and interactions with pathogenic microorganisms. The evaluation of stalk mechanics has focused primarily on the end‐of‐season outcomes and defined differences among inbred and hybrid maize genotypes. However, there is a gap in understanding how these different end‐of‐season outcomes are achieved. This study measured stalk flexural stiffness in maize inbred genotypes across multiple environments and in maize commercial hybrid genotypes under different disease states. Under all conditions, stalk flexural stiffness followed a biphasic trajectory, characterized by a linear increase phase and a sustained phase. Within a genotype, the environment or disease state altered the rate of increase in the linear phase but did not impact the timing of transition to the sustained phase. Whereas between genotypes, the timing of transition between phases varied. Destructive 3‐point bend tests of inbred stalks showed that the trajectory of stalk mechanics is defined by the bending modulus, not the geometry. Together, these results define a biphasic trajectory of maize stalk mechanics that can be modulated by internal and external factors. This work provides a foundation for breeding programs to make informed decisions when selecting for optimized stalk mechanical trajectories, which are necessary for enhancing resilience to environmental stresses.
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- Award ID(s):
- 2040346
- PAR ID:
- 10615021
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- The Plant Journal
- Volume:
- 123
- Issue:
- 1
- ISSN:
- 0960-7412
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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