Histochemical detection of Blueberry latent virus in highbush blueberry plant

Blueberry latent virus (BBLV) was detected in 27 of 95 asymptomatic highbush blueberry trees in a blueberry field in Japan. In situ hybridization showed that the viral RNAs were detected in the palisade mesophyll, spongy mesophyll and vascular bundle of leaves. In western blot analysis, an antibody to the viral protein encoded by open reading frame 1 (ORF1) reacted with a 48-kDa protein specific for blueberry trees in which BBLV was detected. Immunogold electron microscopy revealed that amorphous bodies in the cytoplasm of blueberry cells were labeled with antibodies to the ORF1 protein.