Pollen collections.

<p>Mean (±SD) fresh weights of pollen collections for control (black) and neonicotinoid-exposed (white) colonies over the course of the treatment period (pollen-trap contents were weighed in 2-2–3 days intervals throughout the study).</p

Dynamics of honeybee colony performance.

<p>Data of all three endpoints number of adult bees (A), eggs and larvae (B) and pupae (C) for the different pollen feeding treatments (black  =  control; red  =  neonicotinoids) and honeybee strains (circles  =  strain A; crosses  =  strain B). The data were obtained at four successive colony assessment dates (X-axis subpanels within figures) performed before (Spring 2011) and directly after the 1.5 months of experimental pollen feeding (Summer 2011), 3.5 months after the treatment (Autumn 2011) and one year later (Spring 2012). Estimated numbers on the Y-axes are truncated for adult bees and pupae for better overview.</p

Model-based estimates of contrasts and corresponding significance levels of the treatment effect (neonicotinoid <i>versus</i> control) and honeybee genetics (strain A <i>vs.</i> strain B).

<p>Results are shown in the transformed scale for the three response variables adult bees, eggs and larvae and pupae assessed directly after the 1.5 months of treatment (Summer 2011), 3.5 months later (Autumn 2011) and 1 year later (Spring 2012). For adult bees and eggs and larvae (the models that included a significant threefold interaction between treatment, honeybee strain and assessment date) contrasts for treatment effects were also computed within individual honeybee strains at each assessment date. <i>P</i> values are adjusted for multiple testing. ***<i>P</i><0.001; **<i>P</i><0.01; *<i>P</i><0.05; <b>·</b> 0.05<<i>P</i><0.1.</p