Nanofertilizers for sustainable crop nutrition and production: A review

Abstract

Agriculture worldwide faces major challenges from growing populations, declining fertilizer performance, and environmental damage from overusing conventional fertilizers. Traditional fertilizers work poorly—crops absorb only 10-20% of applied phosphorus and 30-60% of nitrogen, while the rest is lost through leaching and runoff, damaging soils and polluting water. Nanotechnology offers a better solution through nanofertilizers that release nutrients slowly, improve availability, and increase plant uptake. In this review, we discuss different methods to make nanofertilizers (top-down, bottom-up, and biological), along with various types such as nanoscale inputs, additives, and coating materials. Carrier systems like nano-zeolites, nano-chitosan, and nano-biochar hold and release nutrients much better than conventional fertilizers, lasting 40-50 days instead of just 4-10 days. Different application methods like seed coating, soil mixing, drip irrigation, and foliar spraying are greatly improving crop growth, yield, quality, and stress tolerance. Nanofertilizers boost nutrient efficiency significantly, with biosynthesized forms reaching 80-85% nitrogen efficiency compared to only 30-35% for conventional sources, while reducing pollution. However, concerns about nanoparticle toxicity at high levels, production costs, and long-term environmental effects need more research for safe agricultural use.