Leaves of young Nicotiana glutinosa and Nicotiana tabacum var. Xanthi nc plants were rub inoculated with tobacco mosaic virus (TMV) before and after aphid inoculation with potato leafroll virus (PLRV). Local necrotic lesions developed on all leaves inoculated with TMV. After 4-6 weeks, systemic necrotic lesions developed on leaves, stems and tips of plants inoculated with both TMV and PLRV but not in plants inoculated with either virus individually. TMV could be rub transmitted from the systemic necrotic lesions of dually infected plants, but is could not be transmitted from non-necrosis caused collapse of some dually infected plants. Re-growth from the base of such plants was initially non-necrotic but a few necrotic lesions developed on young leaves after plants reached the 10-15 leaf stage. TMV could not be rub transmitted from non necrotic re-growth but could be graft transmitted to healthy gene tobacco scion. TMV could not be transmitted by rub inoculations or by graft transmission from non-inoculated leaves and stems of plants inoculated with TMV only. Concentration and distribution of PLRV was not affected by dual infection with TMV.