Toxin complex a (Tca), a high molecular weight insecticidal protein complex produced by the entomopathogenic bacterium Photorhabdus luminescens, has been found to be orally toxic to both the Colorado potato beetle, Leptinotarsa decemlineata, and the sweet potato whitefly, Bemisia tabaci biotype B. The 48 hour LC50 for Tca against neonate L. decemlineata was found to be 2.
View Article and Find Full Text PDFFive different combinations of fluorescent tubes (UV-B/UV-B, UV-B/UV-A, UV-A/ UV-A, UV-B/White, White/White) were used to determine relative effects of UV and visible light on the nucleopolyhedroviruses (NPV) of Helicoverpa zea and Spodoptera exigua. For both viruses, the greatest inactivation occurred with exposure to UV-B radiation. Both virus concentration and radiation exposure time influenced the rate and degree of inactivation.
View Article and Find Full Text PDFLaboratory studies were initiated to determine the relationship between virus concentration and radiation-caused inactivation of NPVs from Helicoverpa zea (HzSNPV) and Spodoptera exigua (SeMNPV). In the laboratory, a UV-B/UV-A system was used for inactivation studies. For both viruses inactivation was dependent upon both length of UV exposure and virus concentration.
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