The use of nanotechnology in plant-based agricultural systems offers significant potential for improving crop yield, sustainability, and resilience. This chapter thoroughly examines the diverse functions of nanomaterials, namely green-synthesized and biogenic nanoparticles, in seed priming, nutrition delivery, pest management, stress alleviation, and crop surveillance. Nanopriming enhances germination rates, seedling vigor, and abiotic stress tolerance via molecular and physiological alterations. Advanced nanobiosensors provide real-time detection of soil nutrients, pathogenic organisms, and plant stress indicators, hence enhancing precision agriculture. The environmental and toxicological consequences of nanoparticle utilization, particularly their interactions with soil microbiota, bioaccumulation, and phytotoxicity, necessitate a thorough assessment. The chapter addresses contemporary issues, encompassing technical, regulatory, and public perception obstacles, as well as knowledge deficiencies regarding plant–nanoparticle interactions. It further emphasizes future opportunities, particularly the integration of nanotechnology with genomes, artificial intelligence, and intelligent delivery systems for climate-resilient agriculture. This chapter offers a comprehensive review of how responsibly used nanotechnology might transform sustainable agriculture by integrating recent advancements, difficulties, and potential solutions. It emphasizes the necessity for interdisciplinary research, regulatory alignment, and stakeholder involvement to guarantee the secure and equitable implementation of nano-enabled advances in worldwide food systems.