Nanoparticle Applications in Plant Biotechnology: A Comprehensive Review

Nanotechnology is becoming a key tool in plant biotechnology, enabling nanoparticles (NPs) to deliver biomolecules with high precision and to enhance plant and tissue resilience under stress. However, the literature remains fragmented across genetic delivery, in vitro regeneration, stress mitigation, and germplasm cryopreservation, and it still lacks standardized, comparable protocols and robust long-term safety assessments-particularly for NP use in cryogenic workflows. This review critically integrates recent advances in NP-enabled (i) genetic engineering and transformation, (ii) tissue culture and regeneration, (iii) nanofertilization and abiotic stress mitigation, and (iv) cryopreservation of plant germplasm. Across these areas, the most consistent findings indicate that NPs can facilitate targeted transport of DNA, RNA, proteins, and regulatory complexes; modulate oxidative and osmotic stress responses; and improve regeneration performance in recalcitrant species. In cryopreservation, selected nanomaterials act as multifunctional cryoprotective adjuvants by suppressing oxidative injury, stabilizing cellular membranes, and improving post-thaw viability and regrowth of sensitive tissues. At the same time, NP outcomes are highly context-dependent, with efficacy governed by dose, size, and surface chemistry; formulation; plant genotype; and interactions with culture media or vitrification solutions. Evidence of potential phytotoxicity, persistence, and biosafety risks highlights the need for harmonized reporting, mechanistic studies on NP-cell interfaces, and evaluation of environmental fate. Expected outcomes of this review include a consolidated framework linking NP properties to biological endpoints, identification of design principles for application-specific NP selection, and a set of research priorities to accelerate the safe and reproducible translation of nanotechnology into sustainable plant biotechnology and long-term germplasm preservation.