Behavior of common bean genotypes in relation to mineral N fertilization and seed Rhizobium inoculation

Abstract

In order to evaluate the response of bean genotypes to different strategies of N supply, three field experiments were carried out. The statistical design was randomized blocks, with three replications in a 7 x 4 factorial scheme, involving seven bean genotypes and four kinds of N supply: 1) PK + N (urea source, 20kg/ha at
planting and 30kg/ha at covering), 2) PK + Rhizobium inoculation, 3) Only Rhizobium inoculation and 4-control (without fertilizer and without Rhizobium inoculation). The inoculum was made with peatland of Rhizobium tropici
strain SEMIA 4077 or its mixture with R. leguminosarum bv. phaseoli strain SEMIA 4080 in the proportion of 500g
of inoculum: 25kg of seed. Grain and shoots yield and nodules dry weight were evaluated. The grain yield of the common bean was dependent of the bean genotypes, of the mineral N fertilization and of the seed inoculation, but there was not differential behavior of the genotypes in relation to these treatments.