Abstract

The pollen-borne raspberry bushy dwarf virus (RBDV) is a serious pathogen of Rubus worldwide and it is proving difficult to control its spread and effects in crops. Of several distinct isolates of RBDV, we have completely sequenced and studied in detail isolates D200 (the Scottish type isolate), RB (a natural variant able to overcome the RBDV resistance gene, Bu) and Can-S (a laboratory variant that produces severe symptoms in herbaceous test plants). We report sequence comparisons between these isolates. In approaches to produce red raspberry cultivars resistant to RBDV, especially RBDV-RB isolates, 4 viral gene constructs under the control of a novel promoter derived from strawberry vein banding virus was used in Agrobacterium tumefaciens-mediated transformations. We also report apparent resistance to RBDV-RB in an infectible raspberry cultivar, due possibly to somaclonal variation.