Laser-Based Biostimulation, Optical Sensing, and Targeted Physical Control Across Crop Production and Postharvest Stages: Progress and Outlook

Agricultural production faces increasing pressure to improve efficiency while reducing chemical inputs and environmental impacts. Laser-based technologies have attracted attention because their wavelength, energy input, exposure duration, and spatial delivery can be adjusted for different biological targets and operational purposes. This review provides a stage-oriented synthesis of laser-based biostimulation, optical sensing, and targeted physical control across crop production and postharvest stages, including seed treatment and seedling establishment, field growth management, ripening and quality assessment, and postharvest preservation. Rather than treating laser-based technologies as a single uniform approach, this review focuses on technical functions, key operating parameters, possible interaction mechanisms, and evidence levels. Particular attention is given to how wavelength, power density, delivered energy dose or fluence, spot size, and exposure duration affect biological responses, sensing performance, and physical treatment efficacy. Current evidence indicates that many applications remain limited to laboratory studies, controlled-environment tests, field demonstrations, or engineering prototypes. Major challenges include parameter standardization, mechanistic validation, environmental robustness, model transferability, crop or product safety, equipment cost, and system integration. Future research should emphasize mechanism-informed dose–response assessment, adaptive sensing and control, multi-source data fusion, product-specific validation, and techno-economic evaluation.