# Surface Application of Different Insecticides Against Two Coleopteran Pests of Stored Products
## 3 Results
### Mortality of Lasioderna serricorne  
Adults of _L. serricorne_ indicated various effects depending on both the insecticide formulations and different types of surfaces (Table 1). On day 3, regardless of surface type, alpha-cypermethrin achieved 100%, while pirimiphos-methyl and spinosad showed slightly lower efficacy on plastic and metallic surfaces, with mortality rates of 81.6% and 76.6%, respectively (Table 3). By day 7, in all cases, mortality levels reached close to 100% and no significant differences were recorded among the types of surfaces tested. Finally, after 14 and 21 days of exposure, all insecticides achieved 100% mortality across all surface types, illustrating the high efficacy of the treatments (Table 3). For both species, in all cases, delayed effects were also recorded, and complete control was achieved. \begin{table}
\begin{tabular}{l l l l l l} \hline \hline \multicolumn{1}{c}{**Days**} & \multicolumn{1}{c}{**Surface Type**} & \multicolumn{1}{c}{**Control**} & \multicolumn{1}{c}{**Alpha-**} & \multicolumn{1}{c}{**Primiphos-**} & \multicolumn{1}{c}{**Stinosed**} \\  & & & & **Cypermethrin** & **Methyl** & **Spinosad** \\ \hline \multirow{4}{*}{3} & Concrete & 0.0 \(\pm\) 0.0 & 0.0 \(\pm\) 0.0 a & 0.0 \(\pm\) 0.0 a & 95.8 \(\pm\) 3.2 a \\  & Metallic & 0.0 \(\pm\) 0.0 & 100.0 \(\pm\) 0.0 b & 12.5 \(\pm\) 2.5 b & 96.6 \(\pm\) 1.6 a \\  & Plastic & 0.8 \(\pm\) 0.8 & 100.0 \(\pm\) 0.0 b & 0.8 \(\pm\) 0.8 a & 80.8 \(\pm\) 6.5 b \\  & Ceramic & 0.0 \(\pm\) 0.0 & 100.0 \(\pm\) 0.0 b & 3.3 \(\pm\) 2.4 a & 100.0 \(\pm\) 0.0 a \\  & Test-statistic & 3.00 & 23.00 & 15.17 & 13.36 \\  & \(p\) & 0.392 & \textless{}0.001 & 0.002 & 0.004 \\ \hline \multirow{4}{*}{7} & Concrete & 3.3 \(\pm\) 2.1 a & 70.0 \(\pm\) 19.1 & 15.8 \(\pm\) 3.5 a & 100.0 \(\pm\) 0.0 \\  & Metallic & 69.1 \(\pm\) 5.9 b & 100.0 \(\pm\) 0.0 & 98.3 \(\pm\) 1.6 b & 100.0 \(\pm\) 0.0 \\  & Plastic & 1.6 \(\pm\) 1.0 a & 100.0 \(\pm\) 0.0 & 0.8 \(\pm\) 0.8 a & 100.0 \(\pm\) 0.0 \\  & Ceramic & 100.0 \(\pm\) 0.0 b & 100.0 \(\pm\) 0.0 & 90.8 \(\pm\) 4.3 b & 100.0 \(\pm\) 0.0 \\  & Test-statistic & 20.56 & 6.26 & 20.04 & - \\  & \(p\) & \textless{}0.001 & 0.100 & \textless{}0.001 & - \\ \hline \multirow{4}{*}{14} & Concrete & 88.3 \(\pm\) 4.4 a & 92.5 \(\pm\) 5.1 & 80.0 \(\pm\) 3.4 a & 100.0 \(\pm\) 0.0 \\  & Metallic & 100.0 \(\pm\) 0.0 b & 100.0 \(\pm\) 0.0 & 100.0 \(\pm\) 0.0 b & 100.0 \(\pm\) 0.0 \\  & Plastic & 99.1 \(\pm\) 0.8 a & 100.0 \(\pm\) 0.0 & 26.6 \(\pm\) 4.9 a & 100.0 \(\pm\) 0.0 \\  & Ceramic & 100.0 \(\pm\) 0.0 a & 100.0 \(\pm\) 0.0 & 100.0 \(\pm\) 0.0 b & 100.0 \(\pm\) 0.0 \\  & Test-statistic & 18.17 & 6.26 & 22.25 & - \\  & \(p\) & \textless{}0.001 & 0.100 & \textless{}0.001 & - \\ \hline \multirow{4}{*}{21} & Concrete & 100.0 \(\pm\) 0.0 & 100.0 \(\pm\) 0.0 & 100.0 \(\pm\) 0.0 b & 100.0 \(\pm\) 0.0 \\  & Metallic & 100.0 \(\pm\) 0.0 & 100.0 \(\pm\) 0.0 & 100.0 \(\pm\) 0.0 b & 100.0 \(\pm\) 0.0 \\  & Plastic & 100.0 \(\pm\) 0.0 & 100.0 \(\pm\) 0.0 & 83.3 \(\pm\) 3.0 a & 100.0 \(\pm\) 0.0 \\  & Ceramic & 100.0 \(\pm\) 0.0 & 100.0 \(\pm\) 0.0 & 100.0 \(\pm\) 0.0 b & 100.0 \(\pm\) 0.0 \\  & Test-statistic & - & - & 22.42 & - \\  & \(p\) & - & - & \textless{}0.001 & - \\ \hline \hline \end{tabular}  
* Within each exposure interval and insecticide, means followed by the same letter do not differ significantly according to the Kruskal-Wallis _H_-Test at \(p\)\(<\)0.05. Where no letters exist, no significant differences were noted.  
\end{table} 
Table 2: Mean mortality (% \(\pm\) SE) of _Tribolium castaneum_ adults after exposure to three different insecticides (alpha-cypermethrin, pyrimiphos-methyl, and spinosad) on four surfaces (concrete, metallic, plastic, and ceramic) for 3, 7, 14, and 21 days (total degrees of freedom = 3), n = 24.