Arabidopsis thaliana was susceptible to eight out of ten investigated viruses with six of which it did not show any symptoms of local infection; this appeared only in two cases.A. thaliana was a symptomless carrier for three viruses. The considerably distinct systemic symptoms after the infection with turnip yellow mosaic, tomato black ring, cucumber mosaic and cabbage black ring viruses make possible a very reliable and specific distinction of the causal agens.A. thaliana could be used for these viruses as a differential host.