Location: Sugarcane Research
2023 Annual Report
Objectives
Objective 1: Determine and evaluate critical water efficiency optimization parameters that impact sugarcane crop production systems in temperate environments.
Sub-objective 1.A: Improve crop coefficients for reference ET models that are reliable along the sugarcane life cycle and across sugarcane growing areas in U.S. with differing climatic zones and water regimes, including deficit and excess-water conditions.
Sub-objective 1.B: Improve ET models for water management at field to regional level by separating transpiration and soil evaporation fluxes using stable isotopes of hydrogen and oxygen in water.
Objective 2: Develop holistic stochastic optimization models and decision support tools to improve the sustainability of sugarcane production systems in temperate environments.
Objective 3: Evaluate and/or develop conservation best management practices that positively influence soil water and carbon cycling in sugarcane production systems in temperate environments.
Sub-objective 3.A: Characterize how long-term (16+ y) sugarcane crop residue management affects soil moisture storage, C sequestration, and crop yield.
Sub-objective 3.B: Characterize how new tillage and fallow cover cropping practices affect soil moisture storage, C sequestration, and crop yield.
Approach
Through greenhouse and field experiments, improve crop coefficients for reference evapotranspiration (ET) models that are reliable along the sugarcane life cycle and across sugarcane growing areas in U.S. with differing climatic zones and water regimes, including deficit and excess-water conditions; and Improve ET models for water management at field to regional level by separating transpiration and soil evaporation fluxes using stable isotopes of hydrogen and oxygen in water. Employ data collected in the field to populate DSSAT input modules to evaluate how changing climatic conditions will affect sustainable sugarcane production. Characterize how long-term (16+ y) sugarcane crop residue management affects soil moisture storage, carbon sequestration, and crop yield. Characterize how new tillage and fallow cover cropping practices affect soil moisture storage, carbon sequestration, and crop yield.
Progress Report
Year 1 of the new project has been productive. Laboratory equipment was procured and installed that will enable isotopic water analysis. A custom glass distillation train was constructed and installed to extract water samples from roots, shoots, and soil samples for isotopic analysis. Successful installation of minirhizotron tubes required modification of giddings probe to accommodate 45-degree angle insertion of mini-rhizotron tubes. This fabrication was completed. Mini-rhizotron tubes were installed in five sugarcane varieties and root growth data for one growing season was collected. Sugarcane was harvested from this test and ratoon root data is being collected now.
Decision Support System for Agrotechnology Transfer (DSSAT) templates were constructed from existing weather data. This involved redesigning the usual data management template to accommodate DSSAT entry requirements. This task is completed for weather data and is near complete for crop management and plant data templates. Entry of 2022-2023 data is on-going.
Soil samples were collected and frozen prior to analysis for chemical parameters. This is pending determination of soil microbial analyses to be completed as part of the Long-Term Agro-ecosystem Research network collaborative project with Mississippi and Arkansas ARS scientists. Sugarcane harvest was complete and crop residue management was conducted. The second ratoon crop is growing and will be harvested in 2023.
Accomplishments
1. Monitoring rooting behavior with in-situ sugarcane root imaging. The purpose of this research is to understand the development and behavior of sugarcane root systems in Louisiana such as the response in roots to winter conditions and mechanized harvesting. Roots, being underground, are difficult to visualize and monitor through time, so much of the basic understanding of sugarcane root system structure and their function is lacking, yet roots are critical for supporting the stalks and providing nutrient and water for sugarcane production. This is especially true in Louisiana, where sugarcane, a tropical grass, is being cultivated in a temperate region. To conduct this research, we installed 48 minirhizotrons under eight sugarcane varieties that allow us to image sugarcane roots throughout the crop cycle. The installation of the minirhizotrons and the development of a method of imaging and analyzing the roots provides a method of monitoring root growth that can be employed in many research studies. Until now no work on roots had been done in Louisiana partly because of the difficulty of monitoring roots in the field. With this method in place other research studies can be done to determine how roots are affected by cultural practices such as mechanized harvesting in an effort to reduce the impact of harvesting on sugarcane, so that sugarcane production is higher in subsequent harvests. The sugarcane industry is keen on this research because it provides them with information of what is happening belowground. This root monitoring method opens the doors to future research that farmers are interested in such as the effect of harvesting on sugarcane regrowth (ratooning).
Review Publications
Ellsworth, P.Z., Ellsworth, P.V., Mertz, R.A., Koteyeva, N.K., Cousins, A.B. 2023. Cell wall properties influence leaf water isotope enrichment depending on transpiration rates. Plant, Cell & Environment. pgs. 1-17. https://doi.org/10.1111/pce.14612.
Menefee, D.S., Scott, R.L., Abraha, M., Alfieri, J.G., Baker, J.M., Browning, D.M., Chen, J., Gonet, J.M., Johnson, J.M., Miller, G.R., Nifong, R.L., Robertson, P., Russel, E.R., Saliendra, N.Z., Schreiner-Mcgraw, A.P., Suyker, A., Wagle, P., Wente, C.D., White Jr, P.M., Smith, D.R. 2022. Unraveling the effects of management and climate on carbon fluxes of U.S. croplands using the USDA Long-Term Agroecosystem (LTAR) network. Agricultural and Forest Meteorology. 326. Article 109154. https://doi.org/10.1016/j.agrformet.2022.109154.
Hoover, D.L., Abendroth, L.J., Browning, D.M., Saha, A., Snyder, K.A., Wagle, P., Witthaus, L.M., Baffaut, C., Biederman, J.A., Bosch, D.D., Bracho, R., Busch, D., Clark, P., Ellsworth, P.Z., Fay, P.A., Flerchinger, G.N., Kearney, S.P., Levers, L.R., Saliendra, N.Z., Schmer, M.R., Schomberg, H.H., Scott, R.L. 2022. Indicators of water use efficiency across diverse agroecosystems and spatiotemporal scales. Science of the Total Environment. 864. Article e160992. https://doi.org/10.1016/j.scitotenv.2022.160992.
Ellsworth, P.Z., White Jr, P.M. 2022. Row spacing and the use of plant-available water in sugarcane cultivation in water-abundant Louisiana. Agronomy. 12(7):1586. https://doi.org/10.3390/agronomy12071586.
