The Application of Nanotechnology for Micronutrients in Soil-Plant Systems

Micronutrients (MNs) are important to world agriculture and human health. Over 3 billion people across the world suffer from micronutrient deficiencies. Zinc (Zn), iron (Fe), manganese (Mn) and copper (Cu) have become yieldlimiting factors and are partly responsible for low food nutrition. Although crops use low amounts of MNs (<2.4 kg/ha), about half of the cultivated world’s soils are deficient in plant bioavailable MNs, due to their slow replenishment from the weathering of soil minerals, soil cultivation for thousands of years and insufficient crop fertilization. Relevant MN deficiencies occur more frequently in neutral to alkaline soils, under anaerobic conditions and in arid or semi-arid regions. The MN use efficiency (MUE) of most commercial fertilizers added to soils or foliage is 2.5% to 5% of applied, due to their rapid stabilization by soil components, low leaf penetration and low mobility in plants. In soil-plant systems, fertilizer-MNs interact with macronutrients resulting in synergistic, antagonistic or neutral response affecting yield and food quality. Thus far, conventional and newer fertilizer technologies and products are unable to synchronize the MN release from fertilizer according to crop demand during the growing season, resulting in low MUE. New efforts to improve crop yield, food nutrition and fertilizer-MUE involve the use of micro- and nanoencapsulation, nanomaterials (NMs), nanodevices and nanoparticles (NPs) of Zn, Fe, Mn and Cu oxides. Fertilizer products appear to increase MUE as follows: soluble salts < chelates < microcapsules ≤ nanocapsules = nanoparticles. Many of the effects of the new fertilizer materials on crop yield and quality, human health and environmental risks remain largely unknown. Nanobiotechnology will occupy a prominent place in transforming agricultural systems and food production worldwide in the coming years. This report proposes that the development of a MN intelligent nanofertilizer (INF) delivery platform may result in significant increases of MUE and food quality by enabling the synchronization of MN release from fertilizers according to crop demand. The novel MN-INF product development needs adequate financial support and a multidisciplinary team of scientists.
Nanotechnology, Micronutrients, Food security, Crop yield
C.M. Monreal, M. DeRosa, S.C. Mallubhotla, P.S. Bindraban and C. Dimkpa, 2015.The Application of Nanotechnology for Micronutrients in Soil-Plant Systems. VFRC Report 2015/3. Virtual Fertilizer Research Center, Washington, D.C. 44 pp.; 1 tables; 5 figs.; 270 ref