Sensor feedback system enables automated deficit irrigation scheduling for cotton

Susan A O'Shaughnessy; Paul D Colaizzi; Craig W Bednarz

doi:10.3389/fpls.2023.1149424

Sensor feedback system enables automated deficit irrigation scheduling for cotton

Front Plant Sci. 2023 Mar 9:14:1149424. doi: 10.3389/fpls.2023.1149424. eCollection 2023.

Authors

Susan A O'Shaughnessy¹, Paul D Colaizzi¹, Craig W Bednarz^{2

3}

Affiliations

¹ Conservation and Production Research Laboratory, USDA-ARS, Bushland, TX, United States.
² Semi-arid Agricultural Systems Institute and West Texas A&M University, Canyon, Amarillo, TX, United States.
³ Texas A&M AgriLife Research, Amarillo, TX, United States.

Abstract

Precision irrigation technologies using sensor feedback can provide dynamic decision support to help farmers implement DI strategies. However, few studies have reported on the use of these systems for DI management. This two-year study was conducted in Bushland, Texas to investigate the performance of the geographic information (GIS) based irrigation scheduling supervisory control and data acquisition (ISSCADA) system as a tool to manage deficit irrigation scheduling for cotton (Gossypim hirsutum L). Two different irrigation scheduling methods automated by the ISSCADA system - (1) a plant feedback (designated C) - based on integrated crop water stress index (_iCWSI) thresholds, and (2) a hybrid (designated H) method, created to combine soil water depletion and the _iCWSI thresholds, were compared with a benchmark manual irrigation scheduling (M) that used weekly neutron probe readings. Each method applied irrigation at levels designed to be equivalent to 25%, 50% and 75% replenishment of soil water depletion to near field capacity (designated I₂₅, I₅₀ and I₇₅) using the pre-established thresholds stored in the ISSCADA system or the designated percent replenishment of soil water depletion to field capacity in the M method. Fully irrigated and extremely deficit irrigated plots were also established. Relative to the fully irrigated plots, deficit irrigated plots at the I₇₅ level for all irrigation scheduling methods-maintained seed cotton yield, while saving water. In 2021, the irrigation savings was a minimum of 20%, while in 2022, the minimum savings was 16%. Comparing the performance of deficit irrigation scheduling between the ISSCADA system and the manual method showed that crop response for all three methods were statistically similar at each irrigation level. Because the M method requires labor intensive and expensive use of the highly regulated neutron probe, the automated decision support provided by the ISSCADA system could simplify deficit irrigation management of cotton in a semi-arid region.

Keywords: crop water stress index (CWSI); infrared thermometry; soil water sensing; variable rate irrigation (VRI); wireless sensor networks.

Grants and funding

The authors declare that this study received funding from the US-Israeli Binational Agricultural Research and Development (BARD) fund for project IS-5218-19, “Spatiotemporal Decision Support Systems for Recognizing Variability and Managing Precision Irrigation in Field Crops”; and the Ogallala Aquifer Program, a consortium between USDA-Agricultural Research Service, Kansas State University, Texas A&M AgriLife Research & Extension Services, Texas Tech University, and West Texas A7M University. The funders were not involved in the study design, collection, analysis, interpretation of data, the writing of this article, or the decision to submit it for publication.