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Gypchek The gypsy moth nucleopolyhedrovirus product
TM Biocontrol-1
Douglas-fir Tussock moth virus (TM Biocontrol-1)

NPV virus

Photograph: nucleopolyhedrosis virus (NPV).
Click on image for larger photo.

Wild populations of the Douglas-fir tussock moth have several naturally-occurring diseases that cause mortality to certain life stages of the insect during the course of an outbreak.  The agentsnucleopolyhedrosis virus (NPV) that cause these diseases are bacteria, fungi, and viruses, among others.  Research during the 1960's to mid-1980's, mostly by U. S. Forest Service scientists, determined that a nucleopolyhedrosis virus , or NPV for short, (family Baculoviridae; genus Baculovirus Subgroup A), caused considerable mortality of tussock moth larvae during the later stages of tussock moth outbreaks (3rd and 4th year of an outbreak), and was largely responsible for natural collapse of many of the tussock moth outbreaks that occurred in western North America.

Photograph: Douglas-fir Tussock moth killed by virus.
Click on image for larger photo.

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