Mortality of Blattella Germanica (Blattodea: Blattellidae) Due To the Percentage of Exposure To Pesticides and Type of Surface, Before and After Washing

Abstract:
The cockroach Blattela germanica (L. 1767) is the most important synanthropic specie to develop high populations in habitations. This study has evaluated the mortality of B. germanica exposed to different treated areas in equivalent amount of insecticides to verify the mortality caused by pesticides in cement and tile surfaces before and after washing. The experiments were conducted at the Department Fitossanidade, UNESP, Campus Jaboticabal-SP, Brazil. On the first experiment, the insecticide application was made on Petri dishes in a Potter’s tower, with displayed areas of 25, 50, 75 and 100% in each plate. The second application was performed by spraying pressurized, on tiled surfaces and cement, which were then washed with detergent and water. It was used the insecticide cypermethrin (Cynoff 400 AM) 2.5 c.p. g / L, deltamethrin (250 Deltagard WG) 1.0 c.p. g / L; lambdacyhalothrin (Icon 5 EC) c.p. 5.0 mL / L and an untreated control. Were enclosed for fifteen minutes, five adults on first experiment, and ten on the second one. Mortality evaluations were performed at 0, 1, 2, 4, 24, 48 and 72 hours after confinement. Thus, we conclude that the insecticides used in 50%, 75% and 100% of the area resulting in high mortality of B. germanica. The insecticide cypermethrin had a significant effect of shock effectively. The insecticides cypermethrin, deltamethrin and lambdacyhalothrin are efficient in controlling B. germanica, before washing the surface of tile. The efficiencies of these insecticides are bigger in tiled surface than on cement surface. After washing, the control efficiencies decreased to both surfaces.