Disease management during bloom affects the floral microbiome but not pollination in a mass-flowering crop

Flowering crops are heavily managed during bloom to both promote pollination and prevent disease. Disease management practices can alter the floral microbiome, including pathogens and non-target microbes. However, whether agrochemical presence or altered microbiome composition affect pollinator foraging and pollination services is unclear.
We assessed the effects of orchard management tactics and landscape context on the flower microbiome in almond, Prunus dulcis. Fourteen orchards (5 conventional, 4 organic, 5 conventional with habitat augmentation) were sampled at early and peak bloom to characterize bacterial and fungal communities associated with floral tissues. The surveys were complemented by an artificial flower experiment to assess the effects of fungicides and microbes on honey bee foraging. Finally, a field trial was conducted to test the effects of fungicides and microbes on pollination. 
As bloom progressed, bacterial and fungal abundance and diversity increased across all f...