Proximal thermal imaging‐based irrigation scheduling for bread wheat in Egypt

Abstract

Owing to the significance of leaf and air temperature differences (ΔT) under arid conditions, this study aimed to prove the proximal thermal imaging concept for irrigation scheduling under controlled irrigation amounts for wheat in Egypt. This led to variation in leaf relative water content (RWC), soil water content (SWC) and ΔT and allowed us to obtain relationships. Two experiments were conducted in the 2022 winter season under different agroecological conditions. The average temperature of bright leaves (T leaf ) and average temperature of entire images (T image ) were estimated. Strong inverse relationships were observed between the bright leaves and air temperature difference (ΔT-L) and both RWC and SWC, with R 2 values of 0.736 and 0.844, respectively. Additionally, the entire image and air temperature difference (ΔT-I) showed strong inverse relationships, with R 2 values of 0.735 and 0.880, respectively. The study proved reliability for detecting water stress, instantly measuring RWC and SWC and providing thermal-based irrigation scheduling in newly reclaimed lands. This study recommends determining ΔT thresholds for various crops. The study was the first step to prove the concept under controlled conditions and provide ΔT thresholds. The next step will capitalize on findings to schedule irrigation under uncontrolled conditions in farmer fields in the 2023 winter season to test the ability to achieve an impact. K E Y W O R D S leaf temperature thresholds, newly reclaimed lands, precise irrigation Résumé En raison de l'importance des différences de température des feuilles et de l'air (δt) dans des conditions arides, cette étude visait à prouver le concept d'imagerie thermique proximale pour la planification de l'irrigation dans des quantités contrôlées d'irrigation pour le blé en egypte. Cela a entraîné une variation de la teneur en eau relative des feuilles (RWC), de la teneur en eau du sol (CFC) et de δt et nous a permis d'obtenir des relations. Deux expériences ont été menées au cours de la saison d'hiver 2022 dans des conditions agroécologiques différentes. La température moyenne des feuilles brillantes (Tleaf) et la température moyenne des images entières (Timage) ont été estimées. De fortes Article title in French: Planification de l'irrigation par imagerie thermique proximale pour le blé panifiable en egypte.

Enhancing Wheat (Triticum aestivum L.) Crop Yield and Water Use Efficiency: A Study on Canopy Air Temperature Difference-Based Drip Irrigation Scheduling in a Semi-Arid Region of Western India

“…One line of research has focused on the use of leaf or canopy temperature as an indicator of plant water stress (Omar and Nangia, 2023). There have been many attempts to relate leaf and canopy temperatures to plant water stress conditions to guide irrigation scheduling as stated by Jackson (1982), Jones (2004), and Moran (2004).…”