In response to BYDV-PAV infection, our data suggest an up-regulation of GRAS TF in the susceptible barley genotype Graciosa only at day 10 post-infection, while in wheat a remarkable up-regulation was shown for the susceptible genotype Semper and to a lesser extent for Tobak, but later, 30 dai, only a slightly increased expression for Semper remained. The gene discussed is TF; the disease is infection.