Abstract
Six sweet potato [Ipomoea batatas (L.) Lam.) cultivars '049', 'A28/7', 'TIS 2328/6', 'C26/7', '02/62', and 'C9' were each grown in pure stands and with maize (Zea mays L.) cultivar 'X304B' planted simultaneously at two populations (18 315 and 36 630 plants ha-1) in two field trials. Cultivars 'C26/7', 'TIS 2328/6', and 'A28/7' produced less (P < 0.05) total dry matter in mixtures with maize than in pure stands, but harvest indices were not affected. Total and marketable tuber yields of 'TIS 2328/6' and 'C26/7' were also significantly (P < 0.05) lower in mixtures with maize due to the production of smaller tubers than those from pure stands. lntercropping with maize did not adversely affect tuber yield from '049' and 'A28/7'. Cultivar '049' was the most tolerant to intercropping, apparently because of its late tuber-bulking characteristics. In all mixtures, the joint Land Equivalent Ratio of sweet potato and maize exceeded unity, and productivity was highest in the mixture with maize planted at 18 315 plants ha-1.
