Effect of seasonal-regular pesticide application on earthworm Lumbricus sp. in an apricot orchard

In this study, Common pesticides; methyl parathion (as an insecticide), copperoxychloride (as a fungucide), tebuconazole (as a fungucide) and thiram (as a fungucide)were used to determine the effects on non-target organisms. The effects of selectedpesticides on earthworm (Lumbricus sp.) were determined using selected biochemicalmarkers. The study area was divided into four regions (main study area, fungucide area,insecticide area and insecticide+fungucide area) and pesticides were applied at earlyspring-2005. Parathion methyl + copper oxychloride was used in first application(March 2005) into the main study area. The second pesticide application was done atApril-2005 and tebuconazole was used. Final pesticide spreyed at May-2005 andmixture of parathion methyl + thiram was used in this case. Earthworm samples werecollected from each application area and other areas at 1st, 3rd, 5th, 7th and 10th daysafter pesticide applications. The earthworm samples were used to determineethoxyresorufin-O-deethylase (EROD), glutathion-S-transferase (GST),carboxylesterase (CE) and acetylcholinesterase (AChE) activities from microsomal orcytosolic preparates.Some enzyme activities were changed in all application areas at 1st day after allof the pesticide applications. Results also showed that, pesticide mixture is moreeffective than simple application of selected chemicals on earthworm. It is also decidedthat, selected biomarkers EROD, AChE and CE are the suitable enzymes to determinethe effects of this kind of pesticide exposure in an apricot orchard, in thisecotoxicological microcosm study. The pesticides used in this study caused soilpollution and affects adversely to this non-target organisms in the ecosystem.KEYWORDS: pesticide, earthworm, Lumbricus sp., toxic effect