Mechanical inoculation of Arabidopsis thaliana ecotype Columbia with tomato spotted wilt virus led to viral replication and spread as determined by dot blot and ELISA analysis. Severe symptoms were observed three to four weeks post-inoculation. Early symptoms were manifested as chlorotic spots on uninoculated leaves. Later in the infection process, some plants showed complete chlorosis and wilting prior to bolting. Bolts that were developed by infected plants were chlorotic and deformed. These preliminary results suggest that A. thaliana could become a model system for the genetic analysis of host factors required for the replication of viruses in the family Bunyaviridae, which includes viruses that cause important diseases of both plants and animals.