Converting Iron Wastes to Nano Scale Zero Valent Iron: A Tool for Improving the Yield and Physiological Properties of Vegetables in Hydroponic Systems-Case Study, Broccoli in Floating System

Abstract

New achievements should be directed towards reducing iron deficiency in the plant and ultimately increasing the nutritional quality of agricultural products. An experiment was conducted to find the effects of various ratios of nano scales zero valent iron to iron chelate (NI/ Iron chelate) (0:100, 25:75, 50:50, 75:25 and 100:0) at a concentration of 1.5 mg L-1 in different pH levels (5.5, 7.0 and 8.5) of nutrients solutions on yield, growth and photosynthesis pigments of broccoli plants in floating system. The experiment was designed as a factorial combination and treatments were arranged in a completely randomized design with three replicates. The results indicated that the growth of broccoli plants in terms of biomass and photosynthesis pigments were significantly affected by both different levels of NI/ Iron chelate and nutrient solution pH. The highest amount of head fresh weight was observed in concomitant application of 50:50 ratio and pH=7.0 nutrient solution, which was 32.53% more than the control treatment. The results of this experiment showed that the use of different ratios of NI/Iron chelate up to 50:50 levels improved the growth and yield of broccoli plants. As first report, the results of this experiment suggested that nano scale zero valent iron powders could increase the growth and yield of broccoli plants.