Abstract
Different concentrations of the two biopesticides; spinosad and proclaim, were tested to evaluate their insecticidal effects against the adults of peach fruit fly, Bactrocera zonata Saunders. Moreover, their impact on some biochemical parameters of the adults of the fly. Recorded results showed that both spinosad and proclaim were effective on B. zonata. LC25s was 0.156 and 0.233, LC50 was 0.42 and 0.620mg/l and LC90 was 2.909 and 3.978mg/L for spirtosad and proclaim, respectively. Spinosad was more potent than proclaim on B. zonata. Toxicity results were correlated with some biochemical parameters such as electrophoratic patterns of protein and some isozymes. SDS-PAGE of protein showed a pattern of 7 normal bands in the control, while spinosad and proclaim treated flies showed 10 and 11 bands, respectively, with molecular weights ranged from 122.0 to 12.5 KDa. Treatment with spinosad and proclaim resulted in absence of two bands (9 and 10), with molecular weights 20.5 and 19.2 KDa. Proclaim treated flies were characterized by the presence of unique protein band number 4, with a molecular weight 51.7 KDa. Isozymes electrophoresis showed various changes as a result of utilization of spinosad than proclaim on B. zonata. a, beta-esterases and Acid phosphatase showed 20, 17 and 20% polymorphism compared with control, respectively, while the most isozymes affected by biopesticides treatment were recorded in case of alcohol dehydrogenase, which showed changes 71 and 43% polymorphism in both of spinosad and proclaim, respectively. No effect appeared on aldehyde oxidase. This application may help to use biopesticides instead of conventional chemical pesticides to control B. zonata and to throw light on the role of some isozymes in the modes of action of these biopesticides.