Effect of Iron and Zinc Nanoparticle, Chelate, and Sulfate Foliar Applications to Deficient Maize.

Improving uptake, mobility, and utilization of foliar-applied iron (Fe) and zinc (Zn) is essential for increasing plant biomass and grain yield. The objective of this study was to compare the effect of foliar-applied Pheroid nanoparticle, chelate, and sulfate forms of Fe and Zn, (0.11; 0.22 kg Fe ha^-1 and 0.45; 0.90 kg Zn ha^-1) on biomass, nutrient uptake and mobilization on Fe and Zn-deficient maize (Zea mays L.) grown in a hydroponics greenhouse study. Nanotechnology is a recent methodology that reports to improve dermal penetration, timed-release, and mobility of active ingredients in both animal and plant systems. These properties have potential to increase the effect of foliar-applied nutrients. (-)Fe and (-)Zn hydroponics solutions reduced Fe and Zn biomass, 79 and 11 percent and reduced nutrient concentrations 37 and 55 percent from V5 to V9 in their respective trials to below reported critical values thus establishing ideal experimental parameters for testing the effect of foliar-applied compounds. The upper rate of foliar-applied Fe and Zn in nanoparticle, chelate, or sulfate form increased their respective concentrations in foliage by 90, 120, and 42 percent in the Fe study and by 158, 183, and 120 percent in the Zn study. There was no effect of the Fe or Zn foliar treatments in any form or rate on foliage or root biomass, or mobilization of the applied nutrient.