Essential oil microencapsulated fumigant: an innovative technology against Zabrotes subfasciatus (Boheman, 1833) (Coleoptera: Chrysomelidae: Bruchinae)

The fumigating effect of essential oils on the control of stored-grain pests has been widely studied. However, bioactive compounds with low molecular weight, high volatility, and sensitivity to light and heat; thus, the development of new technologies, such as the microencapsulation process, is needed to improve their use in agriculture. The objective of this research was to develop and characterize a microencapsulated fumigant based on citronella essential oil (MFCEO), Cymbopogon nardus L., for the management of Zabrotes subfasciatus (Boheman, 1833) (Coleoptera: Chrysomelidae), one of the main storage pests of beans. The resulting microparticles were a white powder with 100–1300 µm, 3.29% moisture content, a bimodal distribution, and smooth circular particles. The fumigant activity showed LC ₅₀ 0.46 g.L ⁻ ¹ and 6.49 µL.L ⁻ ¹ of air and LC ₉₉ of 7.6 g.L ⁻ ¹ and 12.94 µL.L ⁻ ¹ of air for MFCEO and essential oil, respectively. Thus, this is the first report of a MFCEO for the management of Z. subfasciatus .