Figure 1.
Foraging honeybee (Apis mellifera L.) and microscopic views of pollen.
A) Pollen forager bee with pollen-load (black arrow); B) SEM micrograph of the entire pollen-load (70×); C) higher magnification of the pollen-load (2000×); D) pollen grains of a mixed-species pollen-load (6000×).
Figure 2.
Viral loads of flower pollen and pollen load samples.
The values are expressed as mean DWV copy number per 20 milligram of sample ± standar error (UFP: unvisited flower pollen;VFP: visited flower pollen; PL: pollen load).
Figure 3.
Infectivity of pollen-associated DWV.
DWV-positive bees injected with VFP (a); PL (b); IB (c). X axis: days p.i.; Y axis: viral load in bee's heads; *: replicating virus detected after strand-specific RT-PCR; **: replicating virus detected after strand-specific seminested RT-PCR.
Figure 4.
Comparison of DWV infectivity in VFP1, PL1 and IB1 supernatants.
Figure 5.
Detection of replicating virus by strand specific RT-PCR in injected Apis mellifera (A) and Osmia cornuta (B) bees.