Location: Plant Physiology and Genetics ResearchTitle: Use of hydraulic traits for modeling genotype-specific acclimation in cotton under drought
|WANG, DIANE - University Of Buffalo|
|VENTURAS, MARTIN - University Of Utah|
|MACKAY, SCOTT - University Of Buffalo|
|Hunsaker, Douglas - Doug|
|GORE, MICHAEL - Cornell University - New York|
|PAULI, DUKE - University Of Arizona|
Submitted to: New Phytologist
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/7/2020
Publication Date: 10/5/2020
Citation: Wang, D.R., Venturas, M.D., Mackay, S.D., Hunsaker, D.J., Thorp, K.R., Gore, M.A., Pauli, D. 2020. Use of hydraulic traits for modeling genotype-specific acclimation in cotton under drought. New Phytologist. 228(3):898-909. https://doi.org/10.1111/nph.16751.
Interpretive Summary: Plant growth models can provide explanations for how and why different crop genotypes (a set of plant genes) are affected by environmental stresses. ARS scientists in Maricopa, Arizona, explored whether such models can be useful for determining field-based genetic differences in plants. They employed a hydraulics-plant growth coupled model called Terrestrial Regional Ecosystem Exchange Simulator (TREES) to study cotton in a drought experiment in Maricopa. Cotton was found to be very vulnerable to water stress and the TREES model showed that the soil type with high content helped reduce the effects of water stress on certain genotypes. This study lays the groundwork for future strategies that integrate water-plant growth models to improve genetic and physiological understanding of crop drought response.
Technical Abstract: Understanding the genetic and physiological basis of abiotic stress tolerance under field conditions is key to varietal crop improvement in the face of climate variability. Here, we investigate dynamic physiological responses to water stress in silico and their relationships to genotypic variation in hydraulic traits of cotton (Gossypium hirsutum), an economically important species for renewable textile fiber production. In conjunction with an ecophysiological process-based model, heterogeneous data (plant hydraulic traits, spatially-distributed soil texture, soil water content and canopy temperature) were used to examine hydraulic characteristics of cotton, evaluate their consequences on whole plant performance under drought, and explore potential genotype × environment effects. Cotton was found to have R-shaped hydraulic vulnerability curves (VCs), which were consistent under drought stress initiated at flowering. Stem VCs, expressed as percent loss of conductivity, differed across genotypes, whereas root VCs did not. Simulation results demonstrated how plant physiological stress can depend on the interaction between soil properties and irrigation management, which in turn affect genotypic rankings of transpiration in a time-dependent manner. Our study shows how a process-based modeling framework can be used to link genotypic variation in hydraulic traits to differential acclimating behaviors under drought.