Understanding the bees-mediated movement of pollen-borne viruses at the cultivated peach-wild cherry agroecological interface

Pollen-mediated virus transmission is a common problem in fruit crops. Prunus necrotic ringspot virus (PNRSV) and prune dwarf virus (PDV) are pollen-borne ilarviruses of important stone fruit crops, including peaches, which can result in substantial yield losses. Our two-year survey of peach orchards demonstrates that bees carry PNRSV and PDV-infected pollen during bloom and move along orchard blocks. Based on morphology, Bombus, Apis, Andrena, Eucera, and Habropoda are the predominant bee genera that were captured in peaches. Moreover, PNRSV has been found in wild cherry (Prunus serotina) near peach orchards in South Carolina and Georgia. As wild Prunus spp. such as wild cherry are abundant at peach orchard edges, it is still unclear if PNRSV and/or PDV are moving from wild Prunus to peach trees (or vice-versa). Our driving question of this research is: What is the role of bees in carrying virus-infected pollen between wild hosts and peach orchards? We hypothesize that multiple PNRSV isolates in bee pollen samples might resemble known PNRSV isolates found in cultivated peaches and wild cherries, as bees visit different flowers during bloom. Leveraging sequencing data of pollen collected from bees will help determine what plants the bees visit during the peach bloom period. Sequencing and characterizing virus isolates within bee pollen samples will also enhance our understanding of virus movement at the agroecological interface. This work provides insights into the role of bees as a bridge in virus movement at the wild cherry-cultivated peaches interface.