Figure 7.

Fold increase in deformed wing virus (DWV) and Black queen cell virus (BQCV) titers relative to the nurse bees sampled while tending queen cells. (A) and (B) are from queens reared from grafts of larvae from outside colonies and reared in either outside colonies or those in an enclosed flight area fed pollen-1 (chlorpyrifos) or pollen-2 (chlorpyrifos with added Pristine^®). (C) and (D) are from larvae grafted from and reared into queens in colonies fed pollen-1 or 2 or reared in outside colonies. Estimates of virus titers were made from 3 queen larvae and 3 virgin queens in each treatment group with the exception of outside larvae that were reared in colonies fed pollen-2 where two virgin queens were analyzed. Estimates of virus titers in nurse bees were based on samples of 9–15 bees per treatment group.