Premium
Effects of Copper Chelates on Lettuce Response, Leaching, and Soil Status
Author(s) -
Gonzalez Demetrio,
Alvarez Jose M.
Publication year - 2013
Publication title -
soil science society of america journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.836
H-Index - 168
eISSN - 1435-0661
pISSN - 0361-5995
DOI - 10.2136/sssaj2012.0164
Subject(s) - leaching (pedology) , copper , chelation , environmental chemistry , environmental science , chemistry , agronomy , soil water , soil science , inorganic chemistry , biology , organic chemistry
Copper deficiencies have a major effect on both the quality and yield of crops, but the application of the most effective Cu fertilizers could pose a potential problem due to possible losses from leaching. The objective of this study was to evaluate the effects of Cu‐ N ‐2‐hydroxyethyl‐ethylenediaminetriacetate (Cu‐HEDTA), Cu‐ethylenediaminetetraacetate (Cu‐EDTA), and Cu‐diethylenetriaminepentaacetate (Cu‐DTPA)–HEDTA–EDTA (Cu‐D–H–E) chelates on: Cu distribution throughout soil and leaching, Cu availability, and lettuce ( Lactuca sativa L.) response in slightly acidic (Typic Haploxeralf) and calcareous soils (Typic Calcixerept) under greenhouse conditions. The behavior of Cu in soil was evaluated by sequential, DTPA–triethanolamine (DTPA–TEA)‐, low‐molecular‐weight organic acids (LMWOAs)‐, and BaCl 2 –extraction procedures. To evaluate the losses of applied Cu, total Cu concentration was determined in leachates. Plant parameters such as dry matter yield, Cu concentrations, and Cu uptake were also studied. In the soils, the main effect of applying the three fertilizers was an increase in the weakly specifically adsorbed Cu fraction. The Cu applied as Cu‐HEDTA chelate showed very low Cu mobility and only descends through the soil, at most, to a depth of 8.9 cm in the calcareous soil. The application of Cu‐EDTA and Cu‐D–H–E chelates produced the greatest movement of Cu through the soils; the 3.0 mg Cu kg −1 application rate of these fertilizers only produced notable amounts of leached Cu in the calcareous soil (8.8 and 11% of applied Cu, respectively). Therefore, high rates of Cu fertilization with Cu‐EDTA and Cu‐D–H–E would produce environmental problems due to potential Cu leaching. The DTPA–TEA‐, LMWOAs‐, and BaCl 2 –extraction methods and the water soluble fraction of Cu in soils could be used to estimate Cu concentrations in lettuce plants. The utilization of Cu by lettuce plants was greatest for the application rate of 1.5 mg Cu kg −1 when the Cu treatments were: Cu‐HEDTA in slightly acidic soil, and Cu‐D–H–E and Cu‐EDTA in calcareous soil. These findings could be considered to optimize Cu fertilization and to minimize losses of Cu from land to water.