Residual Effects of Some Pesticides Used in the Apple Cultivation

The aim of this study was to determine residue and half-life between last application and harvest of pyridaben and tebuconazole active substances on Granny Smith apple under field conditions in the Kumlukalan village of Gürsu-Bursa, Turkey. After 1, 6, 14, 21 days, residues on harvested apple of pyridaben and tebuconazole active substances were found to be 0.575, 0.141, 0.137, 0.075 and 0.418, 0.160, 0.108, 0.046 ppm, respectively. Regression charts were created to reveal the degradation curve of pyridaben and tebuconazole active substances. According to these charts, pesticide applications must be in accordance with technical directions. When pyridaben and tebuconazole tolerance in Turkey (0.5 ppm and 1 ppm, respectively) took into account, the period between the last pesticide application and harvest should be 21 days.