Evaluation of larvicidal activity and effects on post embrionary development of laboratory reared Lucilia cuprina (Wiedemann, 1830) (Diptera: Calliphoridae), treated with Brevibacillus laterosporus.

The blowfly Lucilia cuprina is an economically important livestock pest that is also associated with human myiasis. To date, methods including the application of chemical pesticides, plant extracts, insect growth regulators and a range of Bacillus thuringiensis strains have been used, with varying degrees of success, to control this pest. The present study evaluated the larvicidal activity and the induction of sub lethal effects upon post embrionary development following ingestion of 12 strains of Brevibacillus laterosporus, presented individually in the diet as spores. All strains were shown to be larvicidal, with corrected mortality levels of 29 to 54%. No significant differences were observed, in terms of larval weight at the time of abandoning the diet, in the time taken for the initiation of the pupation process, in the duration of the pupation process, the period of adult emergence or cumulative mortality during the transition from larvae to adult. However, an influence upon sex ratio was observed. This study suggests that strains of B. laterosporus hold potential for development as a tool in the biological control of L. cuprina.

Biological activity of Pouteria sapota leaf extract on post-embryonic development of blowfly Chrysomya putoria (Wiedemann, 1818) (Calliphoridae)

Chemical insecticides have been the main way to control synanthropic flies of medical and veterinary importance; however, residuals of these products have become a factor impacting on the environment, as well as the potential toxicological that they may cause damage to humans and domestic animals. Phytochemical screening carried out with the aqueous crude extract of Pouteria sapota (Jacq.) H.E. Moore & Stearn, Sapotaceae, leaves showed that coumarins, reducing sugars, flavonoids and cyanogenic glycosides were its most abundant metabolites. This study evaluated the activity of the crude aqueous extract of this plant on the post-embryonic development of Chrysomya putoria. Larvae treated with 5, 10 and 25% extract showed a decrease in the pupal period and in the newly-hatched larvae to adult period when compared to the control groups. Larvae from the 25% extract group were the lightest (45.8 mg) when compared with the control group (46.5 mg). The larval and newly-hatched larvae to adult stages were more sensitive to the leaf extract from P. sapota (5%) and the treated flies showed the low viability (47.5 and 45.5% respectively). The results demonstrated that topic treatment with P. sapota could alter C. putoria post embryonic development.