Munger black raspberry: Insights into its role as a virus indicator for Rubus species

Munger black raspberry (Rubus occidentalis) has been a preferred indicator for Rubus viruses. The working hypothesis behind the Munger elevated susceptibility to viruses is its ability to sustain elevated virus titers; however, no research has yet explored this concept. To address this, we utilized an infectious clone of blackberry chlorotic ringspot virus to study the differences in virus expression between two Rubus species: R. occidentalis ( Munger) and R. L. subgenus Rubus Watson (blackberry, Natchez). Our data demonstrate that virus accumulation in Munger is over 47,300 times higher compared to Natchez, enhancing our understanding of virus-host dynamics and providing valuable insights into why Munger is a preferred indicator species for virus detection in Rubus spp.