Essential oils profiles in <i>Melicope pteleifolia</i> and <i>Melicope patulinervia</i> and their insecticidal activities against two storage insect species

Food safety is a major concern globally. However, safe and effective insecticidal agents are required. In this assay, the composition and insecticidal effects of essential oils (EOs) in Melicope pteleifolia and M. patulinervia leaves, stems, and fruits against Lasioderma serricorne and Liposcelis bostrychophila were evaluated. The aim of the study was to explore a safe plant source of EOs that can be used to develop insecticides. The EOs in the leaves, fruits, and stems from M. pteleifolia were represented as AMPL, AMPF, and AMPS, respectively. The EOs from the three M. patulinervia parts were represented as BMPL, BMPF, and BMPS. EOs were extracted using the hydrodistillation method. Qualitative and quantitative analyses by GC–MS revealed that the EOs primarily comprised monoterpenoids, sesquiterpenoids, alcohols, and esters. Elsholtzione occurred in high proportions in the plant extracts. The comprehensive evaluation method of weighted coefficient was used to evaluate the exploring potential of each EO based on the insecticidal effects. The results showed that BMPL, AMPS, and AMPL had the highest fumigation, contact, and repellent effects against the insects. BMPL had the highest comprehensive score at 0.91. These findings indicated that all the plant extracts had insecticidal effects, with BMPL demonstrating the highest effect and can be used to develop plant-based insecticides.