Emerging nanoherbicides for next generation of weed control: Strategies and future directions

Weeds represent one of the major biotic stress factors in crop ecosystems, causing approximately 34% reduction in global crop productivity and resulting in an estimated annual economic loss of USD 32 billion. To mitigate yield losses and protect crops, around USD 75.3 billion worth of agrochemicals are applied globally each year. However, the excessive and indiscriminate use of these chemicals has led to severe environmental contamination and potential health hazards. In the context of declining arable land and limited water resources, achieving sustainable agricultural growth now hinges on optimizing input use and adopting modern, eco-efficient technologies to preserve agro-ecological balance. In recent years, nanotechnology-enabled herbicide formulations, commonly known as nanoherbicides, have emerged as a promising alternative for sustainable weed management. These formulations offer enhanced efficacy and environmental safety compared to conventional herbicides. Nanoherbicides require lower application rates and reduced frequency, thereby minimizing the accumulation of chemical residues in soil and water bodies. Furthermore, biodegradable, carrier-based nanoformulations exhibit desirable features such as controlled and prolonged release, targeted action on weed biochemical pathways, improved adhesion to plant surfaces, reduced leaching, and protection of active ingredients (AIs) from rapid degradation. This review explores the emerging nanoherbicide strategies, underlying mechanisms, current advancements, and future research directions shaping the next generation of weed control technologies for sustainable agriculture.