Foliar-Based Nanoformulations: Leads and Flaws

Nanotechnology presents significant opportunities to enhance the quality of life in various fields, including agriculture and food systems. Researchers are actively exploring the innovative ways to develop various nano-based agro products like nanofertilizers, nanopesticides, etc. for foliar application. Foliar application is a method of treating plants by administering liquid formulations directly onto their leaves. Numerous nanoformulations have recently developed to strengthen foliar application’s efficacy by overcoming many inherent challenges like precise targeting of active compounds to specific plant tissues, improved penetration, and controlled release and reduced environmental impact. Nanoencapsulation provides protection against degradation, prolonging the shelf life of formulations. Plants absorb essential nutrients via stomata, cuticle, and trichomes during foliar application. Foliar nanoformulations offer several advantages over conventional counterparts by providing a direct route for nutrient delivery to plants without relying on the root system or requiring adequate topsoil moisture, under adverse conditions such as root diseases and drought. Notably, these formulations require only small quantities for application while delivering nutrients in a controlled and sustainable manner leading to improved and increased yield quality standards. Timing of foliar spray is pivotal for effectiveness and minimal plant stress. Ideal times are early morning or late evening when temperatures are mild, light is low, and wind speed is minimal. This promotes optimal absorption and minimizes heat stress. This chapter delves into the pros and cons of foliar-based nanoformulations and highlights further research and development in this area.