Nitrogen fertilizers are widely used on the cultivation of common bean in Brazil, affecting the production cost and the environment. Biological nitrogen fixation (BNF) can reduce the negative impacts related to N supply. This work aimed to evaluate the agroeconomic response of the inoculated common to N-fertilizer topdressing at different phenological phases of the common bean. N-fertilizer in a total of 90 kg ha −1 was applied in the form of urea at 3 phases: planting (P), phenological phase V4 (V4), and phenological phase R5 (R5) of the common bean, in two field experiments. The used treatments were P 0 V4 0 R5 0 , P 0 V4 45 R5 45 , P 0 V4 90 R5 0 , P 0 V4 0 R5 90 , P 30 V4 30 R5 30 , P 30 V4 60 R5 0 , P 30 V4 0 R5 60 , P 60 V4 30 R5 0 , P 60 V4 0 R5 30 , and P 90 V4 0 R5 0. All treatments were inoculated with peat inoculum containing the commercial strain SEMIA 4077 (Rhizobium tropici). The number of nodules (NN), nodule dry mass (NDM), leaf area index (LAI), root dry mass (RDM), shoot dry mass (SDM), grain yield (GY), production cost (PC), gross revenue (GR), net revenue (NR), and benefit-cost ratio (BCR) were determined. N-fertilizer splitting at any dose and phenological phase decreased NN and NDM. N-fertilizer treatments provided higher LAI and SDM compared with the inoculated treatment (P 0 V4 0 R5 0). Inoculated treatment presented higher GY and lower PC, resulting in greater NR and BCR. Inoculation with Rhizobium tropici provided high nodulation to the common bean and increased its GY in 10.2% as compared with N-fertilization, which allowed a 15.8% and 7.8% higher NR and BCR, respectively, than the N-fertilized treatment.

Biological nitrogen fixation (BNF) is an alternative for the supply of N, aiming at reducing production costs and environmental impacts of common bean crops. This work aimed to evaluate the agroeconomic performance of the inoculated common bean subjected to N-fertilizer application at different phenological phases. N-fertilizer, in a total of 90 kg ha-1 as urea, was applied at 3 phases: planting (P), phenological phase V4 (V4), and phenological phase R5 (R5) of the common bean, in two field experiments. The used treatments were: P0V40R50, P0V445R545, P0V490R50, P0V40R590, P30V430R530, P30V460R50, P30V40R560, P60V430R50, P60V40R530, and P90V40R50. All treatments were inoculated with peat inoculum containing the commercial strain SEMIA 4077 (Rhizobium tropici). The number of nodules (NN), nodule dry mass (NDM), leaf area index (LAI), root dry mass (RDM), shoot dry mass (SDM), grain yield (GY), production cost (PC), gross revenue (GR), net revenue (NR), and benefit-cost ratio (BCR) were determined. Inoculated treatment (P0V40R50) showed higher NN and NDM. Although inoculated treatment (P0V40R50) showed lower values of LAI, RDM, SDM, and GY, inoculation can result in GR, NR, and BCR equal to N-fertilized treatments, depending on the prices achieved for grains sale.

Green manure provides countless benefits to the chemical, physical and biological quality of soils. This study aimed to evaluate the Sesbania herbacea potential, regarding growth and biomass production parameters, as a green manure option in wet floodplain environments. A completely randomized experimental design was used, with measurements repeated over time and six replications. The parameters were evaluated every 20 days (20, 40, 60, 80, 100 and 120 days after emergence - DAE), namely: mean plant height, root and shoot fresh and dry matter biomass, and total plant matter biomass. The legume showed a good development in soil under waterlogged condition, which led to high amounts of phytomass accumulation (approximately 139 t ha-1 of total plant matter biomass and mean height of 4 m at 120 DAE).

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A alimentação é importante na alimentação e, devido ao custo elevado de sementes e de fertilizantes nitrogenados, é necessário o uso de tecnologias que escolham o milho necessário e custo de produção. O trabalho objetivou avaliar o efeito das doses e aplicações de aplicação de A. brasil genéticos de milho nos parâmetros emmorfofisiológicos e fotosintéticos. Utilizou-se o delineamento experimental em blocos casualizados, em esquema fatorial 4x4x2, com três repetições. Os parâmetros; foram teores de clorofila massa fresca do colo, folha e total da avaliação aérea; massa seca do colmo, folha, raiz, total da parte aérea e total da planta; diâmetro médio do colo; volume de raiz; área foliar;altura da planta; número de folhas desenvolvidas; fluorescência inicial, máxima, variável e terminal; e fotoquímica. Quando A. brasilense é aplicada em doses de até 200 mL.ha -1 houve aumento no teor de clorofila total. Para a variedade SCS 156, independente da forma de melhor aplicação ou da dose utilizada, menor produção de fitomassa na parte aérea da planta, já para as variedades SCS 154 e SCS 155, o desenvolvimento das plantas foi observado com dose de até 200 mL. ha -1 .Melhor resposta dos valores morfológicos15, quando a inoculação é realizada via foliar, já para as variedades SCS154, SCS e os valores híbridos híbridos3, com os médios de desenvolvimento das plantas é observado a inoculação via semente.

Com a busca de novas tecnologias para o meio rural principalmente no sistema de produção para agricultura familiar, o capim-vetiver é considerado uma espécie muito segura para se utilizada no sistema de plantio direto por conta de suas características morfológicas e ecológicas, e, além de propicia a grande quantidade de biomassa. O presente trabalho objetivou-se demonstrar a importância do Plantio Direto utilizando o capim Vetiver na agricultura familiar. Conclui-se que com a utilização do capim Vetiver no sistema de Plantio Direto para agricultura familiar é uma ótima alternativa para ser utilizada, por apresentar em pesquisas resultados satisfatórias em relação as suas utilidades, como em suas características morfológicas e ecológicas e benefícios para solo como na sua conservação física e química, e, no desenvolvimento de cultivares.

The positioning of pods in common bean directly affects grain losses in mechanized harvesting. However, only few studies have assessed facttors that can affect pods positioning. The objective of this work was to determine the effect of plant density, nitrogen fertilization, and fertilization depth on the distribution of pods of the common bean. The field experiments were carried out in two cropping seasons, 2017 and 2018, during the winter period in the Cerrado region. The experimental design was randomized blocks in a 4x2 factorial scheme, with four replications. The treatments consisted of the combination of four sowing densities (5, 10, 15, and 20 plants m-1) with two depths of fertilizer application (6 and 12 cm). The results allowed inferring that the depth of the fertilization does not affect the distribution of pods in the common bean. Plant density does not affect common bean grain yield. More than a quarter of the common bean pods of the BRS FC104 are positioned close to the ground, below 100 mm, in the area where harvester machines operate. Nitrogen fertilization and plant density affect the distribution of pods in common bean plants. At higher doses of N (90 kg ha-1), plant density should be increased. On the other hand, at lower doses (45 kg ha-1), plant density must be reduced. It is concluded that the sowing density can be an efficient strategy to provide the highest positioning of pods in the upper part of the common bean plants, reducing harvest loss.