Research Article | Open Access

Volume 2024 |Article ID 0185 | https://doi.org/10.34133/plantphenomics.0185

From Neglecting to Including Cultivar-Specific Per Se Temperature Responses: Extending the Concept of Thermal Time in Field Crops

Lukas Roth ,¹ Martina Binder,¹ Norbert Kirchgessner,¹ Flavian Tschurr,¹ Steven Yates,¹ Andreas Hund,¹ Lukas Kronenberg,^1,2 and Achim Walter¹

¹ETH Zurich, Institute of Agricultural Sciences, Universitätstrasse 2, 8092 Zurich, Switzerland
²Present affiliation: John Innes Centre, Crop Genetics, Norwich NR4 7UH, United Kingdom

Abstract

Predicting plant development, a longstanding goal in plant physiology, involves 2 interwoven components: continuous growth and the progression of growth stages (phenology). Current models for winter wheat and soybean assume species-level growth responses to temperature. We challenge this assumption, suggesting that cultivar-specific temperature responses substantially affect phenology. To investigate, we collected field-based growth and phenology data in winter wheat and soybean over multiple years. We used diverse models, from linear to neural networks, to assess growth responses to temperature at various trait and covariate levels. Cultivar-specific nonlinear models best explained phenology-related cultivar–environment interactions. With cultivar-specific models, additional relations to other stressors than temperature were found. The availability of the presented field phenotyping tools allows incorporating cultivar-specific temperature response functions in future plant physiology studies, which will deepen our understanding of key factors that influence plant development. Consequently, this work has implications for crop breeding and cultivation under adverse climatic conditions.