Abstract
A field study was conducted in Togo, West Africa, to determine the need for and evaluate the effect of fertilizer-N on 23 cultivars of bambara groundnut. All cultivars nodulated freely with the indigenous rhizobia, and usually produced more nodules and greater nodule dry weight in the low-N than the high-N treatment. There was inadequate infectivity or efficacy of the indigenous rhizobia, judging from the fact that the high-N treatment gave significantly higher total dry weight and seed yield than the low-N nodulated plants. Application of high N is therefore considered necessary for high seed yield. There were differences in cultivar responses, reflecting differences in origin and suggesting that cultivars from the wetter zone of Togo and Cameroon adapted better to the experimental site than cultivars from Mali and Senegal which are in a drier zone.