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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 use of plant growth-promoting bacteria combined with Integrated Agricultural Production Systems (IAPS) has resulted in productivity increases in the Brazilian Cerrado region. Thus, the objective was to evaluate the effect of inoculating or not inoculating Azospirillum brasilense on corn and palisade grass seeds (Urochloa brizantha cv. Marandu) on growth, yield components, and dry matter yield of the aerial part and grains in an Oxisol cropped in ICLS and under a no-tillage system for 12 years in an irrigated area. The experimental design was a randomized block design with four replications. The treatments were composed of corn (monoculture) with inoculated seed, corn (monoculture) without inoculated seed, corn + palisade grass (intercropping) without inoculation, corn + palisade grass (intercropping) with inoculation in both seeds, corn + palisade grass (intercropping) with inoculation of corn seeds, and corn + palisade grass (intercropping) with inoculation of grass seeds. At the end of each production cycle, the yield and components of corn, corn straw biomass, and dry matter of palisade grass were evaluated. Considering the optimal conditions of soil provided by liming and fertilization at sowing and nitrogen applied in topdressing, the application of A. brasilense in corn seeds did not show its potential. Intercropped systems inoculated or not with A. brasilense on corn seeds increase grain yield, dry matter production of grass, and nutrient accumulation in the straw, providing greater sustainability to the Cerrado no-tillage system.

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.

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