Use of Optical Brighteners as Radiation Protectants for Gypsy Moth (Lepidoptera: Lymantriidae) Nuclear Polyhedrosis Virus

Abstract

Twenty-three optical brighteners were tested as radiation protectants for the gypsy moth nuclear polyhedrosis virus (NPV). Three brighteners were ineffective (i.e., 70% original activity remained). Eight of the latter 17 brighteners (In-trawite CF, Leucophor BS, Leucophor BSB, Phorwite AR, Phorwite BRU, Phorwite BKL, Phorwite eL, and Tinopal LPW) provided complete protection (i.e., 100% original activity remaining) at a 1% concentration. At lower concentrations, Phorwite AR and Tinopal LPW were superior UV protectants. Mortality rates were also affected by several brighteners (Intrawite CF, Phorwite AR, Leucophor BS, Leucophor BSB, Tinopal LPW), and NPV-exposed insects died more quickly than those exposed to standard NPV + H2O.