%0 Research article
%T Cherry leaf roll virus – an emerging virus in Finland?
%A Bargen, Susanne von
%A Grubits, Elise
%A Jalkanen, Risto
%A Büttner, Carmen
%D 2009
%J Silva Fennica
%V 43
%N 5
%R doi:10.14214/sf.169
%U https://silvafennica.fi/article/169
%X Cherry leaf roll virus, CLRV, is a plant pathogen that infects a variety  of deciduous trees and shrubs in temperate regions. Little is known  about its occurrence at high latitudes and especially in Finnish birch  species. Still, symptoms that seemed to be associated with CLRV such as  vein banding, leaf roll and decline have been observed in birch trees  throughout the country since the summer of 2002. Six different birch  species, subspecies or varieties, i.e. Betula pubescens subsp. pubescens  (downy birch), B. pendula (silver birch), B. nana (dwarf birch), B.  pubescens var. appressa (Kiilopää birch), B. pubescens subsp.  czerepanovii (mountain birch) and B. pendula var. carelica (curly birch)  originating from all over Finland were assessed by  immunocapture-reverse transcription-polymerase chain reaction  (IC-RT-PCR) for CLRV infection. It was shown that CLRV is widely  distributed in B. pendula and B. pubescens throughout the country.  Furthermore, dwarf birch, mountain birch, Kiilopää birch and curly birch  were confirmed to be previously unkown hosts of CLRV. Genetic analysis  of virus sequence variants originating from Finnish birch trees revealed  atypical phylogenetic relationships. In contrast to CLRV isolates from  birches growing in the United Kingdom and Germany which clustered  exclusively within group A, Finnish CLRV isolates belonged either to  group B, D or E. Thus, virus population structure in Finnish birches  seems to be more variable and host plant dependency seems not to apply  for Finnish CLRV isolates.