Synthesis of organic iron chelates and evaluation of their efficiency in improving the growth and yield of Blackgram

Abstract

Supplying a sufficient amount of available iron (Fe) for plant growth in pot culture is a great challenge. The chelators commonly used to supply Fe in pot culture have several advantages and positively affect plant growth. In this research study we have synthesized certain Fe – amino acid and Fe – organic acid chelates, including Fe – glycinate, Fe – citrate and Fe – EDTA and evaluated their efficacy as a Fe source for blackgram grown in pot culture. FTIR analysis shows unbound glycine from chelated one. Free glycine exhibit a vibration peak at 2920 cm-1 that disappear upon chelate formation. The peak at 2920 cm-1 due to twisting vibrating of NH2 groups. Disappearing of this peak indicates that new coordinate bond is formed through the terminal amine groups. The peak at 3153.04 cm-1 and 1327.75 cm-1 is due to weak stretching of symmetric and asymmetric amine vibration. As compared to the position of bands in the spectrum of iron glycinate confirms the chelation of said amino acid with Fe2+ ions. The pot experiment was conducted to study the effect of foliar and soil application of amino acid and organic acid chelated iron on growth of blackgram. The results showed that the foliar spraying of 1% ferrous glycinate resulted in maximum Fe, Zn content, leaf active iron, Catalase and Peroxidase activity. Higher activity of Catalase and Peroxidase confirmed the improvement in plant Fe status. Between the soil and foliar application foliar spraying is better in improving the plant micronutrient content which was evidenced from higher enzyme activities.