Two independent double‐stranded RNA patterns occur in the Finnish Gremmeniella abietina var. abietina type A

Abstract

SummaryThe occurrence of double‐stranded RNA (dsRNA) among isolates of Gremmeniella abietina var. abietina type A was studied. Nine out of the 17 isolates investigated contained dsRNA, but none of them was of ascospore origin. Two fairly different dsRNA patterns were found and they occurred independently of each other. The first was composed of a single approximately 6000 bp long dsRNA molecule. The second was a multisegmented dsRNA pattern composed of three dsRNA molecules with apparent sizes of 1800 1600 and 1200 bp, respectively. In pathogenicity experiments no major differences were observed between dsRNA‐containing and dsRNA‐free isolates.