Release kinetics of nanoherbicides in aqueous and soil environments—a comprehensive review of release dynamics of nanoherbicide in water and soil

Abstract

Herbicides are extensively employed in agricultural systems for effective weed management. Empirical research has demonstrated that plants absorb only a minor fraction of the applied herbicide, with the remainder undergoing various dissipation processes, such as photodecomposition, microbial degradation, adsorption, volatilization, leaching, and chemical degradation. Despite the well-documented adverse environmental and health impacts, herbicides continue to be utilized to enhance crop productivity and ensure food security. This underscores the urgent need for the development of herbicide formulations in view of reduce the dumping of herbicide residues in to the agricultural environment. Nanotechnology presents a viable solution by facilitating the precise and efficient delivery of herbicides, thereby mitigating the risks associated with improper usage and environmental contamination. Nanoherbicides have demonstrated superior weed control efficacy and improved crop yields while significantly reducing the rate of herbicide application. Moreover, two primary release profiles are offered by the controlled release characteristics of nanoherbicides: sustained (gradual) release and stimuli-responsive (triggered) release. Sustained release utilizes a polymeric membrane to regulate herbicide diffusion, ensuring prolonged and controlled effects. On the other hand, herbicide release is triggered by external triggers such as light, pH, temperature, or ultrasound in stimuli-responsive systems. This ensures sustained weed management throughout the crop growing season. This review focuses on the release kinetics of nanoherbicides, drawing on evidence from water release studies and their behavior in soil matrices. The analysis highlights the potential of nanoherbicides to revolutionize weed management practices by combining efficiency with environmental sustainability.