The Effect of Phenoxyacetic Herbicides on the Uptake of Copper, Zinc and Manganese by Triticum Aestivum L.

Abstract

dichlorophenoxyacetic acid (2,4-D) and 4-chloro-2-methylphenoxyacetic acid (MCPA) are active substances in many weed-killer agents commonly used for the protection of crops. The literature data accom- panied by our former studies showed that in weak-acid and neutral environments these compounds react with bivalent metal ions and form complexes of limited solubility in water. It was assumed that the formation of the complexes can also occur between metals present in soil and herbicides used for plant spraying, which can reduce the uptake of the metals by the above-ground parts of the plants. Our studies concerned copper, zinc and manganese determination in wheat cultured using the pot method under laboratory conditions. Cultures were treated after sprouting with either 2,4-D or MCPA. The content of copper, manganese and zinc was deter- mined in the wheat straw. In comparison with the content in plants untreated with herbicides, the respective values were lower by ~50% for Mn, 20% for Cu and 13% for Zn.