No abstract

The Mauritia flexuosa L.f. tree is of immense socioeconomic significance in the Brazilian Middle North Region for its manifold benefits, but mainly for its fruit. However, the potential of this species has still not been extensively studied. The objectives of this work were to study the phenotypic and genotypic correlations between the characteristics of the M. flexuosa fruits and to establish the direct and indirect effects of the secondary characteristics of the fruit on the pulp yield. Samples of ten fruits per genotype were gathered from four natural populations, from 240 different genotypes. These samples were assessed in terms of the fruit, almond and hull weights, equatorial and polar fruit diameters, and the fruit, almond and pulp, volumes, as well as the pulp yield. The genotypic correlations showed greater magnitude, higher than the phenotypic correlations, and both were significant and revealed equal signs. The indirect selection of the M. flexuosa genotypes with greater fruit weight and almond volume favored the increase in the pulp yield in this fruit species.

One of the alternatives to achieve agriculture with sustainability and reduction in production costs, mainly with fertilizers, is the formation of straw from the previous crop and the use of genus Azospirillum bacteria. The objective of this study was to evaluate the agronomic characteristics and yield of soybean, cultivated in areas under straw of sorghum regrowth inoculated or not with diazotrophic bacteria, single or intercropped with Paiaguás grass under Integrated System of Agricultural Production, in Cerrado region. The experiments were carried out in the field, in 2015 and 2016, in Selvíria, state of Mato Grosso do Sul. It was used a complete randomized block design, in a 2 x 2 x 2 factorial arrangement, with four replications, in two agricultural years: with the cultivation of dual-purpose and grain sorghum, single or intercropped with Paiaguás grass, with or without inoculating sorghum seeds with the bacterium Azospirillum brasilense. Soybean production and yield components were evaluated. Inoculation of grain or dual-purpose sorghum seeds with Azospirillum brasilense intercropped with Paiaguás grass, before soybean cultivation, increased the components of production and grain yield of soybean in succession.

The objective of this work was to evaluate the physical attributes of the soil as well as the components of soy production in the different frequencies of soil scarification with and without the use of agricultural gypsum. The experiment was carried out during the 2011/12 and 2012/13 agricultural years in succession of corn crops in the winter and soybean in the summer in Cerrado experimental area, in Selvíria -MS. The experimental design was a randomized block design, in a 3 x 2 factorial scheme (soil management x gypsum), with four replications. The management systems were: no-till system continuous (SPDC), no-till system with scarified every twelve months (SPDE 12), no-till system with scarified every six months (SPDE 6), with or without the use of gypsum. The soil physical attributes were evaluated at depths of 0.0-0.10 and 0.10-0.20 m, as well as the agronomic characteristics of the soybean crop. The no-till system continuous (SPDC) over time with the application of gypsum provided continuous values of soil physical attributes in the two layers and years of cultivation. It was also the system that provided higher values of final population and of the mass of one hundred grains, with no increase in soybean yield.Key words: soil scarification; agricultural gypsum; Glycine max Atributos físicos do solo e fenológicos da soja em diferentes sistemas de manejo e gesso RESUMO O objetivo do trabalho foi avaliar os atributos físicos do solo, bem como os componentes de produção da soja nas diferentes frequências de escarificação do solo com e sem o uso do gesso agrícola. O experimento foi realizado durante os anos agrícolas 2011/12 e 2012/13 em sucessão das culturas de milho no inverno e soja no verão em área experimental de Cerrado, em Selvíria -MS. O delineamento experimental foi o de blocos ao acaso, em esquema fatorial 3 x 2 (manejo do solo x gesso), com quatro repetições. Os sistemas de manejo foram: Plantio Direto Contínuo (SPDC), Plantio Direto Escarificado a cada doze meses (SPDE 12), Plantio Direto Escarificado a cada seis meses (SPDE 6), com ou sem o uso de gesso. Foram avaliados os atributos físicos do solo, nas profundidades de 0,0-0,10 e 0,10-0,20m, bem como as características agronômicas da cultura da soja. O sistema de plantio direto contínuo (SPDC) ao longo do tempo junto à aplicação do gesso proporcionou valores contínuos dos atributos físicos do solo nas duas camadas e anos de cultivo. Também foi o sistema que proporcionou maiores valores de população final e da massa de cem grãos, contundo sem incremento na produtividade da soja.Palavras-chave: escarificação do solo; gesso agrícola; Glycine max

Nitrogen fertilization in crop sorghum during the off-season may have a lower cost-benefit ratio than expected, due to the residual effect of the predecessor crop. However, the use of growth-promoting bacteria can be an economical alternative to increase crop yield in the Cerrado. The objective was to evaluate the response of grain sorghum to nitrogen fertilization and its inoculation by A. brasilense. A complete randomized block design in a 5 x 2 factorial arrangement was used, with five replications of the following treatments: recommended amount of N (120 kg ha-1 of N-urea), divided into 0 %-100 %, 25 % -75 %, 50 %-50 % and 100 %-0 %, in sowing and coverage, respectively, and the control (without N); with and without inoculation via sorghum seed. The morphological and productivity components of the crop were evaluated. The application of 100 % of N in the sowing provided larger plants and the 50 %-50 % installment provided smaller plants. The plants did not respond to inoculation by A. brasilense. The yield components of sorghum grown in succession to soybean, rainfed, do not change due to A. brasilense inoculation and supply or installment of nitrogen fertilization.

The Integrated Agricultural Production Systems (IAPS) under No-Tillage System (NTS), add values to grain production and to livestock activity over the year, besides providing reestablishment of degraded areas. The objective of this work was to evaluate the production costs and profitability of the irrigated corn crop, intercropped or not with Urochloa brizantha cv. Marandu, inoculated or not with Azospirillum brasilense, in the lowland Cerrado. The work was composed of two sequential experiments, conducted in Selvíria-MS, from 2015 to 2016. The experimental design of the two experiments was in randomized blocks with four replicates. The first experiment consisted of six treatments: (a) inoculate crop in single crop, (b) single corn crop without inoculation, (c) intercropping without inoculation, (d) intercropping with inoculation in both seeds, (e) intercropping with inoculation of corn seeds, and (f) intercropping with inoculation of grass seeds. In the corn off-season harvest, for the second experiment, the experimental units with grass were subdivided into three treatments: (a) leaf inoculated grass (250 mL of inoculant), (b) grass broadcast fertilized with urea (200 kg of N ha-1 year-1) in broadcast and (c) grass without fertilization or inoculation. The inputs were the most expensive components in corn production. In the intercropping treatments, where the grass was destined for silage, the profitability indexes were positive, enabling the system regardless of Azospirillum brasilense inoculation.

No abstract

The adoption of diversified agricultural systems that employ integrated cultural practices appears to be the way to sustainably intensify tropical agriculture. Our objectives were to evaluate the dry matter (DM) accumulation of sorghum inoculated with Azospirillum brasilense, with or without a nitrogen fertilization split, intercropped with palisade grass (Urochloa brizantha cv. BRS Paiaguás), and how these practices influenced the nutrition and development of soybean in succession. The design was a randomized complete block in a 2 × 2 × 3 factorial, consisting of sorghum monoculture cropped or intercropped with palisade grass, sorghum either inoculated or not with A. brasilense, and nitrogen applied at 120 kg ha−1 N only at sowing, only at topdressing, or split—30% at sowing and 70% at topdressing at the beginning of the panicle initiation stage. The residual impacts of these treatments on the following soybean crop were also evaluated. Higher DM yield occurred in sorghum inoculated with A. brasilense, however, this result varied by year. The sorghum–palisade grass intercrop produced a higher amount of straw than sorghum monoculture. The nutrition of soybean was adequate regardless of treatments, but grain yield was higher when the sorghum residue was inoculated. The inoculation of A. brasilense in sorghum intercropped with palisade grass increased yield. The nutrition of soybean was adequate regardless of the treatments, while grain yield was higher on the inoculated sorghum residues. The inoculation of A. brasilense in sorghum intercropped with palisade grass increased DM yield. The intercropping increased the production of biomass for animal grazing and DM for soil coverage. The inoculation of sorghum by A. brasilense and its intercropping with palisade grass contributed to higher soybean yield in succession.