Abstract :
The present work designed to assess the effect of Chitin Synthesis Inhibitor (CSI) Lufenuron against the larvae of the housefly, Musca domestica L. (Diptera: Muscidae). Lufenuron was applied at different concentrations (10, 100, 1000 and 2000 ppm) to larval diets. Results recorded a high toxic effectand the determined sub-lethal doses (LC50) were 254.379, 124.108, and 70.109ppm for the first, second and third larval instars, respectively. The ultrastructure investigations of normal and treated Musca domestica larvae were studied to evaluate the effect of tested compounds on cuticle, muscles, and mitochondria. Cuticle structure in untreated larvae consists of the epicuticle exo, endocuticle and epidermis layer.Muscles are made up of a number of fibers; each fiber is bounded by the sarcolemma. The whole fibers appeared to be transversely striated. The essential features of these patterns are the Z, H, A bands and I. Mitochondria are a doubled-membrane-bounded body-containing matrix. While Lufenuron-treated larvae revealed reduced size of both endocuticle and epithelial layer was not arranged in a single layer. The epicuticle exo, endocuticle, was not obviously distinguished. Disorganization of muscle components as compared with normal muscles were the bands and zones are less defined.Mitochondria showed irregular shapes or become disintegrated.These outcomes recommended using Lufenuron in Musca domestica control programs combined with the programs of integrated pest management.
Keyword :
Insect Growth Regulators; Chitin synthesis inhibitors; lufenuron; Musca domestica; Ultrastructure study