Efficacy of Three Plant Oil Extracts and their Nano-Emulsions on the Leaf Miner, Tuta absoluta Larvae (Meyrick) (Lepidoptera: Gelechiidae)

Abstract

In Egypt, tomato crop is the second most important vegetable crop and Tuta absoluta comes among the most serious lepidopterous insects that attaching the tomato crop. Due to the dangers of chemical pesticides, nanoemulsions have recently been in pest control programs. The present study looked into the larvicidal activity of the three plant oil extracts and their nano-emulsions against the second instar larvae of T. absoluta. Spraying method was used for application on the leaves infested with T. absoluta larvae. Results showed that nano-emulsions of essential oils were more effective than traditional essential oils against larvae. The highest mortality proportion caused by the high concentrations of Nano emulsion of essential oils (250 ppm) and essential oils (10000 ppm) under laboratory conditions. But the highest reduction percentage in larvae population was caused by essential oil nano-emulsions under field conditions. As a conclusion, nanoparticles of essential oil have to be used as biopesticides in IPM programs of T. absoluta.

A review on destructive tomato pest, <i>Phthorimaea absoluta</i> (Lepidoptera: Gelechiidae) and its management

“…In ancient times, Egyptians dynasties used botanicals as pesticides (Isman, 2006). Marigold extracts, Mandarin crust oil, camphor oil has been tested against Phthorimaea absoluta shows great mortality (Marouf and Harras, 2022). A laboratory study was conducted to test the insecticidal effects of seven plants (Thymus vulgaris, Ricinus communis, Ononis natrix, Peganum harmala, Argania spinosa, Urtica dioica and Lawsonia inermis) collected and used against the larvae of the T. absoluta shows positive results.…”

Efficacy of Nano-Encapsulated Mandarin Oil using (Polyethylene Oxide/Polyacrylamide) and Gamma Irradiation against Culex pipiens Larvae

“…demonstrate the insecticidal action of orange essential oils (EOs) against various insect pest species (Sayed et al, 2020;Marouf and Harras, 2022). (Brah et al, 2023).…”