Effectiveness of nanobioinsecticide against the mushroom Sciarid, <i>Lycoriella auripila</i> (Diptera: Sciaridae)

Abstract Plant oils, because of their diverse bioactive properties, are considered suitable candidates for formulating biopesticides. This study aimed to investigate the insecticidal potential of a nanoformulation containing: cinnamon, coconut, neem, eucalyptus and citronella oils, against Lycoriella auripila flies in an edible mushroom cultivation medium. The efficacy of these formulations was compared to that of conventional synthetic insecticides, specifically thiamethoxam (25% Water Dispersible Granule, WG) and imidacloprid (35% Suspension Concentrate, SC). The prepared nanoemulsion was characterized using various techniques including gas chromatography, transmission electron microscopy, scanning electron microscopy, dynamic light scattering and gas chromatography-mass spectroscopy. In a contact bioassay conducted on adult insects, the LC50 value of the nanobioinsecticide was recorded as 765.97 mg a.i. l⁻¹. However, the LC50 values of the chemical insecticides showed higher toxicity, with imidacloprid at 116.41 mg a.i. l⁻¹ and thiamethoxam at 201.08 mg a.i. l⁻¹ proving more effective than the nanobioinsecticide against adult sciarids. By contrast, when tested against larvae, the high-concentration nanobioinsecticide achieved 92% mortality at 7 days post-treatment, whereas thiamethoxam and imidacloprid demonstrated 52% and 71% efficacy, respectively. Overall, these findings suggest that the developed nanobioinsecticide shows promising potential for managing mushroom sciarids and could be effectively integrated into an integrated pest management programme within edible mushroom production facilities.