D-limonene-based formulations for the management of Diaphania hyalinata, Plutella xylostella and Spodoptera eridania in a greenhouse

Diaphania hyalinata, Plutella xylostella and Spodoptera eridania are considered important pests in vegetable crops, causing significant production losses. The most common method for managing these pests is the use of synthetic insecticides that cause chain damage, from human health to the environment. A less aggressive alternative is the use of botanical insecticides, such as essential oils, which present themselves as potential for the composition of bioinsecticides. In the present study, the efficiency of formulations based on d-limonene (major compound of the orange peel oil - Citrus sinensis) on the mortality of D. hyalinata, P. xylostella and S. eridania was evaluated. For this purpose, formulations containing d-limonene (2.0%), Tween 80 (0.05%) and water were prepared, combined with different encapsulating agents (xanthan gum, guar gum and maltodextrin) diluted to 2% (v /v). The formulations were sprayed on plants using a sprayer and five second-instar caterpillars were distributed on each plant. The mortality of caterpillars was evaluated 72 h after the application of the formulas. Formulation based on the compound d-limonene with the encapsulating agent guar gum had an effect on the mortality of P. xylostella and S. eridania and formulation with the encapsulating agent maltodextrin had an effect on the mortality of S. eridania.