Residual Contact Toxic Effects of Spinosyn Insecticide, Spinetoram Against German Cockroach (Blatella germanica) Adults

The study investigated the residual contact toxicity of spinetoram suspension, which is spinosyn (semi-synthetic) insecticide, against Blatella germanica (L.) adults on the surfaces of concrete, ceramic floor tile and parquet. On three different surfaces, B. germanica adults were exposed with spinetoram suspension at the rates of 2.5, 5, 7.5, 10, 15, 25, 50, 75, 100 mg(-m2) and mortality of B. germanica adults were recorded at the day of 1, 3, 5, 7 and 9. In all surface applications of spinetoram, exposure times and concentrations caused significant effect on mortality rates of B. germanica adults. Lower concentrations of spinetoram (2.5 and 5 mg(-m2)) on the all- applied surfaces caused low mortality of adults of B. germanica. However, 75 and 100 mg/m(2) concentrations caused 100% mortality of B. germanica adults after 5 day of exposure time. In general, while mortality rate of B. germanica adults increased with exposure time, 100% mortality was not achieved for the concentrations of spinetoram (7.5, 10, 15, 25 and 50 mg(-m2)). There were significant differences in the efficacy of spinetoram concentrations against B. germanica adults on all three applied surfaces. At 100 mg(-m2) concentration of spinetoram, mortality of B. germanica adults was higher on concrete surface than the other surfaces. However, other concentrations of spinetoram, mortality of adults was generally similar on all three surfaces. As a result, spinetoram has potential to control of house pest, B. germanica, and decreases using of dangerous conventional synthetic insecticides.

Automated summary

The study found that the efficacy of spinetoram against Blatella germanica adults varied significantly based on different concentrations and exposure times. Lower concentrations resulted in lower mortality rates, while higher concentrations led to 100% mortality within a shorter period of time. Significant differences in efficacy were observed between different surfaces, with concrete surface showing higher mortality rates at 100 mg/m2 concentration.