DISSIPATION OF DICLOFOP-METHYL AND CLODINAFOP-PROPARGYL IN LEAVES AND SOIL OF WHEAT PLANTS

Abstract

Field experiment was conducted to determine the dissipation of diclofop-methyl and clodinafop-propargyl herbicides in leaves of wheat plant and soil under field conditions during winter season 2013-2014 at the agronomic research area, Faculty of Agriculture, Ain Shams University. Wheat plant was sprayed with the recommended rate of application of diclofop – methyl (750 ml/fed) and clodinfop propargyl (140 gm/fed). The residues of the tested herbicides in wheat leaves and soil were determined after 3h, 7, 14, 21, 28, 35 and 42 days after treatment by gas chromatography using a Ni 63 – Electron Capture Detector (GC-ECD). The average recoveries of diclofop-methyl and clodinafop-propargyl were 88.69 and 87.1 %in leaves and 87.37 and 86.04 % in soil, respectively. The residues of clodinfop propargyl were not detected in all successive intervals of soil and leaves samples except after 3 hours of application on leaves,it reached 0.0078 μg a.i. gm-1. In the contrary, the residues of diclofop-methyl were 5.24 and 3.95 μg a.i gm-1 in leaves after 3 hours and 7 days from application, respectively. Whereas they were 0.44 and 0.14 μg a.i. gm-1 in soil after 14 and 28 days, respectively. These data confirmed that diclofop-methyl was relatively highly persistent in soil and moderate persistent in leaves. The clodinafop-propargyl was rapidly degraded and dissipated in the soil and leaves.