Seasonal abundance, number of annual generations, and effect of an entomopathogenic fungus on Phlebotomus papatasi (Diptera: Psychodidae).
The monthly density of the sand fly, Phlebotomus Papatasi Scopoli (Diptera: Psychodidae), was monitored during 2009 at Burg El-Arab, a rural district located close to the Mediterranean coast of Egypt. The number of annual generations and the efficacy of microbial control by the entomopathogenic fungus, Metrahizium anisopliae (Metsch.) Sorok (Ma79), were determined in the laboratory under atmospheric conditions, simulating those of the animal shelters in the study area. We used two collecting techniques; CDC light traps and oiled paper traps, to quantify sand fly density inside houses and in the open field. Adult flies exhibited a seasonal range from April to December. The seasonal pattern was bimodal, with one peak in July and the second one in October. Calculations of the correlation coefficient (r) revealed a significant role of temperature and relative humidity in the monthly abundance of the sand flies in the study area. P. papatasi colony completed seven annual generations under semifield conditions, but the mean developmental time of each immature stage and the mean total duration of development from egg to adult for each generation varied according to the prevailing temperature. The longest generation time was observed in winter (the mean ± SD was 118 ± 11.70 d), and the shortest one occurred at the highest temperatures in summer (the mean ± SD was 25.21 ± 2.04 d). In microbial control studies, the entomopathogenic fungus, M. anisopliae, was used at 15 × 10(8) spores/g food as a standard dose against the second-instar larvae of P. papatasi at the different seasons during 2009. Mortality reached 100% in winter and decreased to 56.0% as the prevailing temperature increased during the summer season.