Isaria fumosorosea-based zero-valent iron nanoparticles affect the growth and survival of sweet potato whitefly, Bemisia tabaci (Gennadius)

BACKGROUND Nanoparticles can be used for effective pest management as a combined formulation of metal and some other material that has proven efficacy against a given pest. This study reports the synthesis, characterization and efficacy of Isaria fumosorosea-based zero-valent iron (ZVI) nanoparticles against sweet potato whitefly Bemisia tabaci (Gennadius). RESULTS The I. fumosorosea-ZVI nanoparticles showed a characteristic surface plasmon absorption band at 470 nm during UV-visible spectroscopy. The scanning electron micrographs of nanoparticles showed spherical shaped nanoparticles with sizes ranging between 1.71 and 3.0 mu m. The EDX analysis showed the characteristic peak of iron at 0.6 and 6.8 KeV. The XRD analysis showed characteristic peaks at 44.72 degrees, 65.070 degrees, 82.339 degrees and 82.65 degrees. The bioassay results indicated that the percentage of larval mortality of B. tabaci challenged with I. fumosorosea ZVI nanoparticles was both concentration and age dependent. Isaria fumosorosea ZVI nanoparticles showed high pathogenicity against second and third instar nymphs, and pupae with LC50 values of 19.17, 26.10 and 37.71 ppm, respectively. The LT50 was lowest for second instar nymphs (3.15 days) and highest for pupae (4.22 days) when inoculated with a concentration of 50 ppm. CONCLUSION Isaria fumosorosea ZVI nanoparticles can be an eco-friendly tool for effective B. tabaci management. (c) 2019 Society of Chemical Industry