Enhancement of the activity of a nuclear polyhedrosis virus by an optical brightener in the eastern hemlock looper, Lambdina fiscellaria fiscellaria (Lepidoptera: Geometridae)


  • S. Y. Li Natural Resources Canada Canadian Forest Service, Atlantic Forestry Centre P.O. Box 960, Corner Brook Newfoundland, A2H 6J3
  • I. S. Otvos Natural Resources Canada Canadian Forest Service, Pacific Forestry Centre 506 West Burnside Road Victoria, British Columbia V8Z 1M5


The pathogenicity of a nuclear polyhedros is virus originally isolated from Lambdina fiscellaria lugubrosa (Hulst) was compared between treatments with and without the optical brightener Blankophor P167 against L. f. fiscellaria (Guenee) in the laboratory. The brightener significantly enhanced viral activity by 7.5-fold in terms of LD50, and by 22.9-fold in terms of LD95. With the addition of the brightener, the virus killed L. fiscellaria larvae 1.5- to 1.8-fold faster than without the brightener.

Key words: nuclear polyhedrosis virus; Lambdina fiscellaria fiscellaria; optical brightener; virus enhancement