Lupinus albusL. inoculated at 6 weeks andL. luteusL. at 11 weeks by stem injection with a spore–mycelium suspension ofVerticillium albo-atrumReinke and Berth. produced 2.5 and 6.8% infected seeds, respectively. Other methods of inoculation failed to produce seed infection. The pathogen was present internally in infected seeds ofL. luteus, but inL. albusit was superficial. Histological observations indicated that plugs of amorphous material in infected vessels, and branching of the vessels, may serve as barriers to seed infection. Even the low levels of seed infection observed may have economically significant epidemiological implications.