Cherry green ring mottle virus (CGRMV), a member of the genus Foveavirus, infects several Prunus species including sweet cherry, sour cherry, ornamental cherry, peach, and apricot throughout North America and Europe. On sour cherry, the virus causes leaf yellowing and dark mottle around secondary veins. Sweet cherry trees are symptomless hosts of CGRMV. During the 2004 growing season, 27 sour and sweet cherry trees were tested for the presence of CGRMV. RNA was isolated from leaves using an RNeasy kit (Qiagen GmbH, Hilden, Germany) and then evaluated by reverse transcription-polymerase chain reaction (RT-PCR) amplification. Two primer sets, GRMV7956/GRMV8316 (1) and NCP5/NCP3 (2), were used for amplification of the CGRMV coat protein gene (807 bp) or its fragment (366 bp), respectively. The cDNA fragments were cloned into bacterial vector pCR 2.1-TOPO, sequenced and analyzed using the Lasergene (DNASTAR, Madison, WI) computer program. Nucleotide sequence of the C328 isolate (GenBank Accession No. AY841279) was compared with corresponding regions of published sequences of CGRMV isolates. The nucleotide sequence of this isolate was 98% identical to the Leb isolate (GenBank Accession No. AF533157) from sour cherry. The lowest similarity (80%) was between the CP sequences of isolate C328 and an isolate from apricot (GenBank Accession No. AY172334.1). Results of biological indexing on Prunus serrulata ‘Shirofugen’ and ‘Kwanzan’ confirmed the infection of ‘Star’ sweet cherry with CGRMV. The indicators showed leaf epinasty and necrosis of fragments of midrib or veins characteristic for CGRMV (2). The CGRMV infection of the indicators was confirmed using RT-PCR.
References: (1) M. E. Rott and W. Jelkmann. Eur. J. Plant Pathol. 107:411, 2001. (2) Y. Zhang et al. J. Gen. Virol. 79:2275, 1998.
