Abstract
This experiment indicated that most cowpea introductions from Nigeria produced higher yields than one of the best local varieties in Manaus, under the conditions of this experiment. The two highest yielding introductions were TVu 1630 and TVu 2616 with 853 and 847 kg of dry seeds per hectare respectively. Local check, INPA-II, produced only 167 kg/ha. The major reason for the relatively low yields in this experiment was the late time of planting with associated problems of high rainfall during the growing period and high incidence of diseases. Early planting of cowpeas is a must in the varzeas of Amazonas for satisfactory production. TVu 2616 and TVu 1630 required 43.5 and 43.8 days for first 50% flowering (the earliest) and 79.8 and 79.3 days for first 50% ripe pods respectively. These were, however, highly susceptible to the major disease problem in the varzea — cowpea mosaic virus. Only TVx 1836P-66E was observed to be free of symptoms of this virus under the field conditions. A need for breeding for resistance to this virus is indicated to combine the characters for high productivity and quality with those of resistance to this virus in a single cultivar.