Examining the fixation kinetics of chelated and non-chelated copper micronutrient and the applications to micronutrient management in semi-arid alkaline soils

Abstract

Abstract. The relationship between the deficiency of a nutrient in plants and its total concentration in the soil is complex. This study examined and compared the fixation and fixation kinetics of copper (Cu) in chelated (Ethylene diamine tetraacetic acid, EDTA) and non-chelated mixed systems of micronutrients in the semi-arid soils of the Southern High Plains, US using findings from Cu extraction studies and kinetic models. Approximately, 22 % more Cu was fixed in the non-chelated system within the first 14 days with only 7 % difference between the two systems by day 90. Findings suggest a decrease in the effectiveness of chelated micronutrient over time, highlighting the significance of timing even when chelated micronutrients are applied. The strengths of the relationship of change in available Cu with respect to other micronutrients [iron (Fe), manganese (Mn), and zinc (Zn)] were higher in the non-chelated system (R2: 0.68–0.94), compared to the chelated (R2: 0.42–0.81) with slopes of 0.40 (Cu–Fe), 0.31 (Cu–Mn), and 1.04 (Cu–Zn) in the non-chelated system and 0.26 (Cu–Fe), 0.22 (Cu–Mn), and 0.90 (Cu–Zn) in the chelated. Reduction in the amount of available Cu was best described by the power function model (R2 = 0.91, SE = 0.081) in the non-chelated system and second order model (R2 = 0.95, SE = 0.010) in the chelated system. The applications generated from this study could be used as tools for improved micronutrient management and also provide baseline data for future work in other semi-arid/arid alkaline soils of the world. Findings are also more applicable to field settings, an improvement over related previous studies.

Doses e fontes de zinco aplicado via foliar na qualidade de mudas de alface

“…De acordo com alguns autores, o quelato é uma fonte que confere proteção ao elemento. que pode ser mais eficiente na disponibilização de micronutrientes a planta (LÓPEZ-RAYO et al, 2012;UDEIGWE et al, 2016). No entanto, o acúmulo de biomassa das mudas também foi afetado pelas altas dosagens de Zn dessa fonte.…”