As reference genes for quantitative RT-PCR we chose peach orthologs of Arabidopsis F-box family protein (F-BOX) and elongation factor 1-α (EF1-α), which were previously reported to exhibit stable expression upon virus infection in Arabidopsis [29] and the clathrin adaptor complex (CAC) as internal control of the microarray. This evidence concerns the gene ELOF1 and viral infectious disease.