Aduba？？o de cultivares de feijoeiro comum em várzeas tropicais

the bean crop has a high economic and social importance for the brazilian population. however, some aspects should be improved in its cropping system, such as the plants fertilization management. the common bean sub-irrigation, in the rice intercropping, has been a viable alternative for grain yield, in the lowland ecosystem. however, there are just a few studies on fertilization in tropical lowland conditions. thus, this study aimed at evaluating the yield of common bean cultivars grown under tropical lowland conditions and sub-irrigation, in lagoa da confus？o, tocantins state, brazil, in the winter of 2008, by using different fertilizers sources, doses and splittings. the experimental design was randomized blocks, in a factorial scheme (cultivars x forms of fertilization), with cultivars divided into groups (black, carioca and special). the common bean yield was higher with the early nitrogen fertilization, and even higher when it was combined with potassium in topdressing fertilization, being the ouro negro (black group), pitoco (carioca group) and cranberry and brs embaixador (special group) the cultivars that reached the highest grain yields. when the recommended fertilization was used, ouro negro (black group), carioca (carioca group) and jalo precoce and brs embaixador (special group) reached the highest grain yield, for each grain group. yield was higher for the black group cultivars, when compared to the carioca and special groups.