Submitted to: Journal of British Columbia Entomological Society
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: September 22, 2005
Publication Date: December 15, 2005
Citation: Lacey, L.A., Arthurs, S.P., Headrick, H.L. 2005. Comparative activity of the codling moth granulovirus against Grapholita molesta and Cydia pomonella (Lepidoptera: Tortricidae). J. Entomol. Soc. Brit. Columbia. 102:79-80. Interpretive Summary: Codling moth is the most serious insect pest of apple in the Pacific Northwest, and the oriental fruit moth is a widely distributed pest of peach, nectarine, apricot, and apple. The traditional method for controlling these pests is through the routine application of broad spectrum insecticides. The recent registration of 3 commercial formulations of the codling moth granulovirus (CpGV) in the USA and their approval by the Organic Materials Review Institute expands the option for control of codling moth in both organic and non-organic orchards. Among the biological control options available for codling moth, CpGV provides effective and selective control of larvae before or as they enter the apple. Researchers at the USDA-ARS Laboratory in Wapato, WA quantitatively evaluated the Cyd-X formulation of CpGV against OFM and codling moth. Given its virulence and specificity to codling moth, CpGV provides an important intervention for inclusion in pest management programs in pome fruit and walnuts. However, the infectivity of CpGv for OFM is considerably lower that for codling moth, but may provide some control of OFM. Use of CpGV will contribute significantly to the conservation of other natural enemies in the orchard agroecosystem. This microbial control agent will enhance and complement the control activity provided by mating disruption.
Technical Abstract: The granulovirus of codling moth, Cydia pomonella, is highly virulent and now commercialized for codling moth control in pome fruit in the USA and Canada. Comparative assays of the Cyd-X formulation of this virus against another introduced tortricid pest, the oriental fruit moth, Grapholita molesta, revealed a 557 and 589 fold lower susceptibility of neonate larvae compared with the LC50 and LC95 values derived for C. pomonella. Although not as active against OFM as against CM in laboratory bioassays, field activity of Cyd-X against OFM neonates at label rates used for CM control (0.07-0.44 L ha-1) could potentially reduce OFM populations if significant feeding of early instars of the 1st generation larvae occurred on treated foliage.