Microcontroller-based speed-synchronized variable discharge system for liquid urea application in wheat (Triticum aestivum L.)

Efficient nitrogen management in wheat remains a challenge due to losses associated with surface-applied fertilizers. This study presents a microcontroller-based, speed-synchronized variable discharge (MSVD) system for liquid urea application (LUA) to regulate discharge rates in real-time according to the tractor’s forward speed. The system ensures a uniform application rate across the field and automatically stops discharge during turning or stationary conditions, thereby reducing urea wastage and losses. To evaluate the effectiveness of the developed system, field experiments were conducted with five treatments: T1 (100% granular urea), T2 (100% liquid urea), T3 (75% liquid urea), T4 (50% liquid urea), and T5 (control with no urea). The applicator achieved an effective field capacity of 0.24 ha h⁻¹ and fuel consumption of 13.68 L ha⁻¹, indicating satisfactory operational efficiency and field performance. Among the treatments, T4 apply only 50% of the recommended nitrogen dose, achieved grain yields statistically significant to T1 and T2. Furthermore, integration of the MSVD system in LUA reduced nitrogen input and CO₂eq emissions by 46.68% and 21.55%, respectively. The efficacy of the developed MSVD system in delivering precise liquid urea, reducing input costs, and mitigating environmental impacts contributes significantly to sustainable wheat production. Developed a microcontroller-based, speed-synchronized liquid urea application system for precise and uniform nitrogen delivery in wheat. The sensor-based mechatronic system regulates urea discharge in real time and automatically stops fertilizer flow during turning and stationary conditions. Precise liquid urea application reduced nitrogen input by 46.68% and CO₂-equivalent emissions by 21.55% while maintaining grain yield comparable to conventional fertilization.