Características agronômicas do feijoeiro submetido à inoculação e ao tratamento de sementes

Abstract

The aim of this study was to evaluate the effects of inoculation of Rhizobium tropici (strains Semia 4077 / Semia 4080) at different doses on the bean crop, associated or not to the addition of chemical treatment in the seeds, compared with nitrogen fertilization. The experimental design was a completely randomized block with four replications. The eight treatments consisted of inoculation at different doses (100, 200, and 300 g of inoculant per 50 kg seed) in the presence and absence of fungicide (Thiram) and pesticide (Cropstar), besides the control treatments: nitrogen fertilization (60 kg N ha -1 ) and without inoculation and without seed treatment. The cultivar of carioca beans demonstrated increases in the rates of nodulation by the use of inoculation when compared to the control. Nitrogen fertilization reduced almost completely the nodulation of the bean, once the chemical treatment of the seeds showed toxicity to the fixing bactéria when increasing the dose of inoculum. Increased dosage of inoculant without chemical treatment provided nodulation and productivity gains, however the use of fungicide and insecticide in the seed affected the productivity.