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.

Efficiency of the latex from Euphorbia splendens var. hislopii (N.E. Br.) Ursch & Leandri, Euphorbiaceae, in the control of Rhipicephalus (Boophilus) sanguineus (Latreille, 1806) (Acari: Ixodidae)

The aim of this study was to evaluate the effect of the latex from Euphorbia splendens var. hislopii (N.E. Br.) Ursch & Leandri, Euphorbiaceae, on the eggs and engorged larvae of Rhipicephalus (B.) sanguineus (Latreille, 1806) (Acari: Ixodidae). Six aqueous concentrations: 25, 50, 100, 125, 250 and 500 μL/L of the latex of this plant were tested. The control group was tested only with distilled water. The latex of E. splendens var. hislopii presented an LD50 of 18.031 μL/L and LD90 of 84.610 μL/L against the eggs of R. (B.) sanguineus. The larvae of all the groups treated with the latex presented a low survival rate of 0 percent at 25 μL/L, 1 percent at 50 μL/L, 2 percent at 100 μL/L, 3 percent at 125 μL/L, 9 percent at 250 μL/L, 5 percent at 500 μL/L when compared with the control group (91 percent). On day 7 and 14 after the application the latex killed more efficiently the treated groups (25, 50, 100, 125, 250 and 500 μL/L). As from day 21 the latex became less effective for all treatments. Our results clearly show that the aqueous concentration of the latex have a strong effect on tick eggs and larvae suggesting that it could become an important acaricide.