DETECTION OF CHERRY VIRUS A CHERRY NECROTIC RUSTY MOTTLE VIRUS AND LITTLE CHERRY VIRUS 1 IN CALIFORNIA ORCHARDS
S. Sabanadzovic, N. Abou Ghanem-Sabanadzovic, A. Rowhani, J.A. Grant, J.K. Uyemoto
Leaves were collected during 2003 from trees displaying symptoms of vein necrosis, necrotic rusty mottle, necrotic leaf or marked fruit in surveys of sweet cherry [Prunus avium (L.) L. cv Bing] orchards in California. Samples were also taken from trees with leaf necrotic lesion (P. serrulata Lindl. cv Kwanzan) and leaf chlorotic spots (P. avium x P. pseudocerasus cv Colt) from virus disease indexing blocks of Prunus. All of the diseased, but none of the healthy, collections yielded high molecular weight double stranded RNA bands following tissue extraction, purification and electrophoreses in acrylamide gel. Positive amplification in reverse transcription polymerase chain reaction (RT-PCR), with two sets of degenerate primers, was used to detect viruses in the families Flexiviridae and Closteroviridae. Sequence analyses of the RT-PCR products identified Cherry virus A (CVA), Cherry necrotic rusty mottle virus (CNRMV), Cherry green ring mottle virus (CGRMV), Little cherry virus 1 (LChV-1) and Plum bark necrosis and stem pitting associated virus (PBNSPaV). This is the first report of the occurrence of the viruses CVA, CNRMV and LChV-1 in California.