The effect of gemi̇floxacin on some biological traits of drosophila melanogaster (Meigen) (Diptera: Drosophilidae)

Synthetic organic insecticides that is harmful for environment and benefical organisms are intensively used in combating with pest insects. For this purpose, studies on the use of chemicals which are nontoxic or have less environmental impairment are being carried out. The effects gemifloxacin (mesylate salt) that is an antibacterial antibiotic on insect's survival rate and developmental time, male and female adult longevity was examined by adding to artificial diets used for cultivate Drosophilamelanogaster(Meigen) larvae in laboratory condition. The effect of this fluoroquinolone compound on lipid peroxidation product, malondialdehyde (MDA), protein carbonyl (PCO) and glutathione S-transferase (GST) activities in the eggs of D.melanogaster were also investigated. The first-instar larvae were placedonto diets that contain 150, 300, 600 and 900 mg/L of gemifloxacin and were fed until the adult emergence. While the larval survival rate that reached to the 3th. instar in control diet were 88.00 ± 2.00%, this rate in 900mg/L which is the highest tested concentration decreased to 7.00 ± 2.17%. Similar effects were obtained on pupation rate. The time to reach to 3th-instar was 3.29 ± 0.21 days in control, this developmental time in the highest concentration extended to 5.75 ± 1.70 days.Gemifloxacin significantly affected adult developmental time, male and female adult longevity. While female adultlongevity was increased at the 150 mg/L (31.83 ± 1.37 days) compared with control diet (18.31 ± 3.50 days), this was significantly decreased at the highest concentration of gemifloxacin to (10.82 ± 3.19 days).Compared with control diet, the lowest concentration of gemifloxacin, the amount of MDA in eggs was decreased of statistically importantlevel. Relative to the control, the highest concentration of gemifloxacin reduced the amount of protein carbonyl and GST activity in eggs but the lowest gemifloxacin concentration increased theseoxidative stress parameters levels.