Begin by treating the collected carrot callus with the different triazole pesticides under sterile conditions. To do so, in separate glass flasks, mix three grams of carrot callus with 10 milliliters of each pesticide solution prepared in MS medium. Also mix three grams of carrot callus with 10 milliliters of aseptic MS medium in another glass flask.
Incubate the prepared carrot callus samples at 130 rpm and 26 degrees Celsius in the dark for 72 hours. Set all treatments in triplicate. After the incubation, using 0.5 micron glass fiber filters, collect the carrot callus from the medium by filtration.
Wash the callus with ultrapure water three times. Finally, freeze dry the callus using a freeze dryer at 55 degrees Celsius, and then homogenize them using a high throughput tissue grinder at 70 hertz for three minutes. The concentrations of all pesticides exponentially decreased in culture media.
While those in carrot calluses began to increase, peaking at four or eight hours, followed by a gradual decrease. These results suggested that pesticides were quickly taken up and transformed by carrot callus. The temporal recoveries of pesticides in the callous culture system showed that only 8.3 to 11%of pesticides remained after a 72 hour incubation, indicating that most of the pesticides had been transformed into metabolites.
