Susceptibility of larvae of the sandflyPhlebotomus papatasi(Diptera: Psychodidae) toBacillus sphaericus

Abstract

Laboratory experiments were conducted to measure the susceptibility of larvae of the sandflyPhlebotomus papatasiScopoli to the insect pathogenBacillus sphaericusapplied to the larval breeding medium.B. sphaericushad no effect on larvae aged 30 ± 2 days old, but larvae aged 13 ± 2 and 20 ± 2 days were highly susceptible and a clear dose response effect was detected. WhenB. sphaericuswas left in the rearing medium for 18 days there was a significant increase in larval mortality, indicating persistence and possibly recycling. The results support the feasibility of employingB. sphaericusin the integrated control of sandflies.

Toxicity of Bacillus species to larvae of Lutzomyia longipalpis (L. & N.) (Diptera: Psychodidae: Phlebotominae)

“…It may also vary with different conditions such as temperature, nutrition and larval stage. For example, in our results B. sphaericus showed slight pathogenicity to L. longipalpis larvae, but under different conditions, Pener and Wilamowski (1996) observed high susceptibility of 13 + 2 and 20 + 2 days old larvae of P. papatasi to B. sphaericus.…”

“…The susceptibility of sandfly larvae to Bacillus thuringiensis serovar israelensis was previously demonstrated by Barjac et al (1981) against Lutzomyia longipalpis and Phlebotomus papatasi. Pener & Wilamowski (1996) showed that P. papatasi is susceptible to B. sphaericus. Such studies do not clarify the pathogenicity of Bacillus to sandfly larvae and no study has compared toxicity of entomopathogenic Bacillus species to sandfly enized with 1 g of autoclaved larval food, and used during seven days in each experimental lot.…”

Natural breeding places of phlebotomine sandflies

“…However, there were problems with the high cost of the product and its high viscosity, which made it difficult to spray. More encouragingly, selective application of the biopesticide Bacillus sphaericus ( Bs ) into the burrows of host rodents was successful against P. papatasi (Pener et al ., 1996). The Bs toxin works as a stomach poison against target insects, but it remains unclear whether the impact was mostly on immature or adult sandflies.…”

Potential for Bacillus thuringiensis and Other Bacterial Toxins as Biological Control Agents to Combat Dipteran Pests of Medical and Agronomic Importance

“…The toxicity of L. sphaericus strains to a wide range of mosquito species and to a Phlebotomus patatasi (Diptera: Psychodidae) has been reported [182,183] but, since individual toxins were not assessed, the contribution of particular proteins to this activity is unclear.…”