A Remote Sensing Approach for Assessing Daily Cumulative Evapotranspiration Integral in Wheat Genotype Screening for...

Area of Science:

• Agricultural Science
• Agronomy
• Plant Breeding

Background:

• Accurate estimation of actual evapotranspiration (ETa) is crucial for water management in wheat cultivation.
• Traditional ETa models offer limited temporal resolution, hindering integrated water use analysis.
• Developing resource-efficient crop varieties is essential for sustainable agriculture, especially in water-limited environments.

Purpose of the Study:

• To investigate the relationship between daily cumulative actual evapotranspiration (ETa) and wheat crop productivity.
• To evaluate water productivity across different wheat varieties under varying water availability.
• To identify opportunities for breeding water-efficient wheat cultivars.

Main Methods:

• Field trials with 22 wheat varieties under irrigated and rainfed conditions over two years.
• Utilized remote sensing (UAV-RGB) and multiple regression for Leaf Area Index prediction (R²=0.85).
• Integrated remote sensing with energy balance models for daily cumulative ETa estimation.

Main Results:

• A positive asymptotic relationship was observed between crop yield and ETa, indicating a yield plateau beyond a certain water application threshold.
• Genetic analysis revealed no direct correlation between ETa and yield, suggesting selection potential for water efficiency.
• Significant variations in water productivity were found among wheat varieties.

Conclusions:

• Wheat yield gains diminish significantly beyond a specific evapotranspiration threshold.
• Breeding programs can select for water-efficient wheat varieties without compromising yield potential.
• Findings support the development of agricultural practices and crop varieties optimized for water-scarce environments.