Cajanol accumulation was monitored in four cultivars of pigeonpea, Cajanus cajan (L) Millsp, after inoculation with 2 x 10(6) conidia ml-1 of Fusarium udum Butler. Rapid accumulation was observed only in wilt-resistant cultivar ICP 9145. Another wilt-resistant cultivar, ICP 8863, had low levels of cajanol similar to those in wilt-susceptible cultivars ICP 2376 and Malawi local, indicating that rapid cajanol accumulation is not positively correlated with resistance to wilt in pigeonpea. A comparison of various inducing agents showed live conidia of the pathogen to cause more rapid accumulation than the other agents.