Mortality Effect of Spinetoram, Semi-Synthetic Spinosyn Insecticide, Against German Cockroach [Blatella germanica L. (Blattodea: Blatellidae)] Nymphs

Abstract

The study investigated the toxicity of spinosyn (semi-synthetic) insecticide Spinetoram suspension against Blatella germanica (L.) nymphs on three different surfaces; concrete, ceramic and parquet. In this context, biological tests were carried out at 2.5, 5, 7.5, 10, 15, 25, 50, 75, and 100 mg of Spinetoram active substance m-2 concentrations against B. germanica's 3rd and 4th stage nymphs on three different surfaces for 1, 3, 5, 7 and 9 days. In all surface applications of Spinetoram, exposure times and concentrations have been observed to have a significant effect on the mortality rates of B. germanica nymphs. Lower Spinetoram concentrations (2.5 and 5 mg m-2) on all applied surfaces resulted in low mortality in B. germanica nymphs. However, concentrations of 50, 75 and 100 mg m-2 resulted in 100% mortality or near 100% mortality of the B. germanica nymphs after 9 days of exposure. In general, the mortality rate of B. germanica nymphs increased with increasing exposure time, while at relatively low Spinetoram concentrations (7.5, 10, 15, and 25 mg m-2), 100% mortality was not achieved. Significant differences emerged in the effectiveness of Spinetoram concentrations against B. germanica nymphs on three different Spinetoram applied surfaces. At the 100 mg m-2 concentration, the mortality rate of B. germanica nymphs was found to be higher on the concrete surface at the end of the 5th day compared to the other surfaces. However, in other Spinetoram concentrations, nymph mortality at the end of day 5th was generally similar on all three surfaces. As a result, it has been revealed that Spinetoram has the potential to be used in the control of the house pest B. germanica and may reduce the use of traditional synthetic chemicals used in the control of this insect.

Keywords

• spinetoram
• blatella germanica
• nymph
• residual contact toxicity