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The sweet potato whitefly, Bemisia tabaci MED (Gennadius) (Hemiptera: Aleyrodidae), is highly harmful to solanaceous crops. The use of essential oils (EOs) is promising for the management of several insect pests, promoting both lethal and sublethal effects. This study aimed to evaluate the effects of sublethal concentrations of Pelargonium graveolens L'Her (Geraniaceae) EO on the feeding behavior of B. tabaci MED on tomato plants (Solanum lycopersicum L., Solanaceae). For this research, the electrical penetration graph (EPG) technique was used to monitor whitefly stylet activities on their host plants. Two sets of plants were previously sprayed with two concentrations of EO (the LC25 and LC50, which were determined in a mortality test), a third set was treated with the insecticide cyantraniliprole, and a fourth set received a control treatment. Our results indicate that the insecticide cyantraniliprole and the EO could both reduce the stylet feeding activity of B. tabaci MED, as well as reduce the number and duration of phloem sap ingestion events (waveform E2), which could avoid or reduce the transmission of viruses. Thus, the application of sublethal concentrations of P. graveolens EO, as well as exposure to cyantraniliprole, negatively affected the feeding behavior of B. tabaci MED. This information may contribute to the management of this pest and the reduction of the incidence of viruses in tomato production. [ABSTRACT FROM AUTHOR]

• Citrus essential oils and limonene control Mononychellus tanajoa. • Mononychellus tanajoa is a key pest of cassava crops. • Acid lime essential oil decreases the survival of this pest. • It lowers the mortality of the generalist predator Ceraeochrysa caligata. • Ceraeochrysa caligata that survives oil exposure exhibit higher predatory ability. Plant essential oils and their active compounds are recognized as sustainable tools for the management of arthropod pests. Here, the chemical composition of essential oils obtained from different Citrus scions was characterized (i.e., sweet oranges 'Kona' and 'Pera CNPMF-D6'; acid lime 'Persian lime 58' and mandarin 'Piemonte'), and it was evaluated whether these oils could be used to control Mononychellus tanajoa (Acari: Tetranychidae), a key pest of cassava crop. In addition, it was assessed whether exposure to acid lime oil alters the predatory ability of the generalist predator Ceraeochrysa caligata (Neuroptera: Chrysopidae). Predatory bioassays were conducted at two prey densities (i.e., 25 and 50 mites in an arena of 7.1 cm2) immediately after exposure to essential oil and over three consecutive days. Sabinene and linalool were main components in oranges and mandarin oils, while limonene made up more than half of acid lime oil. Based on their LC 50 values, all the essential oils and the limonene isomers equally controlled M. tanajoa. However, mites exposed to the LC 25 or LC 50 of acid lime essential oil exhibited reduced survival rates compared to control. In comparison, exposure to the LC 80 of acid lime essential oil caused low mortality (i.e., 20.4 ± 5%) of C. caligata larvae. Moreover, C. caligata larvae that survived exposure to LC 50 and faced prey scarcity exhibited higher predatory ability immediately after exposure. Overall, this study demonstrates that the essential oils of these Citrus scions could be successfully integrated into management programs for M. tanajoa. [ABSTRACT FROM AUTHOR]