O arroz é um cereal presente na alimentação básica diária brasileira, cuja demanda tem sido maior à medida do aumento populacional. Também é uma cultura que, no regime de terras altas, ganhou espaço por possibilitar aproveitamento e recuperação de áreas. Portanto, pode garantir rentabilidade ao produtor e complementar a demanda pelo grão no mercado. Tendo em vista sistemas de produção sustentáveis e que impulsionam a produtividade do arroz, a inoculação de sementes com Azospirillum pode ser uma alternativa visto que aumenta a superfície de absorção hídrica, nutricional e fornecimento de N via fixação biológica de nitrogênio, além de gerar economia ao produtor pela redução do uso de insumos minerais. Assim, o objetivo do trabalho foi avaliar o efeito da inoculação de sementes de arroz com Azospirillum brasilense associada a doses de adubação nitrogenada em semeadura e cobertura recomendadas (0, 50 e 100%). Utilizou-se o delineamento experimental em blocos casualizados com cinco repetições. O estudo foi desenvolvido no ano agrícola de 2012/13 em um LATOSSOLO VERMELHO Distrófico típico argiloso, em Selvíria – MS. A presença de 100% da dose de N reduziu a massa hectolítrica de grãos. A inoculação com A. brasilense + 50% da dose de N e, ausência de inoculação + 100% da dose de N proporcionaram incremento no número de panículas m-². A inoculação com A. brasilense associada ou não à adubação com 50% da dose de N incrementou a produtividade do arroz de terras altas.

The intense vegetative growth is one of the problems faced by soybean producers, causing the lodging, making difficult and damaging the harvest and, even, the efficiency of the application of agricultural defenses. The use of growth regulators is an important tool in the management of growth, in addition, it can favor the transport of photoassimilates for grain filling. Therefore, the objective was to evaluate the best dose and time of trinexapac-ethyl application in the development and yield of soybean varieties. The experiment was conducted in the Selvíria County, Brazil (20°20′53″ S, 51°24′02″ W). The experimental design was used in randomized blocks with treatments arranged in a factorial scheme 5 x 3 (doses x times), with four replications. The varieties used were the BRS Valiosa RR and the BMX Potência RR, the doses of the growth regulator were 0; 50; 100; 200 and 400 g ha-1 of trinexapac-ethyl (Moddus®) and the application times were at the phenological stages V7, V10 and R2. The varieties BRS Valiosa and BMX Potência, respectively, were obtained at the phenological stage V10, with application of 200 g ha-1 of trinexapac-ethyl, greater dry matter accumulation of leaves and pods. Nevertheless, the same did not act on the foliar area of the BRS Valiosa RR variety in the same way that it did not induce changes in the production components of the BMX Potência RR variety. Regardless of the application period (V7, V10 and R2) and the dose (up to 400 g ha-1), the application of trinexapac-ethyl was not a management capable of influencing the agronomic characteristics and the lodging of the plants in both varieties.

The agricultural use of arbuscular mycorrhizal fungi, such as Rhizoglomus intraradices, can increase the efficiency of phosphate fertilization for the benefit of the corn plant and grain nutrition. In this study, a field experiment was conducted in an area of Selvíria/MS, Brazil, in the years 2019 and 2020, to verify the effects of reduced doses of phosphorus combined with the inoculation of corn seed with R. intraradices on corn plant growth and grain nutrient contents. The experiment was laid in a randomized block design in subdivided plots with four repetitions and twenty treatments resulting from combining five doses of P2O5 (0%, 25%, 50%, 75%, and 100% of the recommended dose) with four doses (0, 60, 120, and 180 g ha−1) of an inoculant containing R. intraradices. Leaf and kernel macro- and micronutrient contents were evaluated. The foliar P content in 2020 was a function of the interaction between phosphate fertilization and AMF inoculation, with the highest leaf P content observed at the 100% of P2O5 combined with AMF inoculation between 120 and 140 g ha−1. In the grains Mg content, an interaction was observed between the two factors in 2020 and the response surface, showing that the highest Mg content was obtained when maximum doses of P2O5 and maximum doses of inoculant were combined. A response surface showed that, in 2020, the highest leaf Zn content occurred when 35–55% P2O5 is applied with no inoculation and when P2O5 is limited to 20–30%, and there is inoculation with doses between 90 and 150 g ha−1. Phosphate fertilization increased foliar K (2019) and Mg (2020) contents, with maximum points at doses of 76.57% and 88.80%, respectively.

O feijoeiro é produzido em todas as regiões do território brasileiro, submetido à diversas condições climáticas e manejos e, em função disto, busca-se cultivares que apresentem elevada produtividade e adaptação ao local de cultivo. Posto isso, o objetivo do trabalho foi verificar o desempenho de diferentes genótipos de feijão comum, no período de outono-inverno em região de cerrado de baixa altitude em dois anos consecutivos. O delineamento experimental utilizado foi o de blocos casualizados com 17 tratamentos, sendo 13 cultivares e 4 linhagens elites, com três repetições. Os genótipos CNFC 10762, CNFC 10729 e CNFP 10794, apresentaram bom comportamento na região, nos dois anos de cultivo, com boa perspectiva de serem lançados como novos cultivares. A instabilidade para a doença antracnose no cultivar TAA Bola Cheia desaconselha a utilização do mesmo na região estudada. A presença de interação genótipo x ambiente indica a necessidade a avaliação dos genótipos em vários anos e locais.

Phosphorus (P) is a plant macronutrient that is indispensable for maize (Zea mays L.) production. However, P is difficult to manage in weathered soils, and its fertilization practice has low efficiency because it becomes unavailable for absorption by plant roots. Symbiosis of plants with arbuscular mycorrhizal fungi increases plant growth and enhances P uptake from the soil that is not directly available to the roots. Thus, the objective of this study was to determine how inoculation with Rhizophagus intraradices and phosphate fertilization interacts and influences the development and productivity of second-crop maize. The experiment was conducted in Selvíria, Mato Grosso do Sul, Brazil, in 2019 and 2020, both in a Typic Haplorthox. A randomized block design in subdivided plots was used for the phosphate application during crop sowing (0, 25, 50, 75, and 100% concentrations of the recommended level), and the secondary treatments were the doses of mycorrhizal inoculant (0, 60, 120 and 180 g ha−1) applied to the seed using a dry powder inoculant containing 20,800 infectious propagules per gram of the arbuscular mycorrhizal fungus R. intraradices. Only in the first year of the experiment, inoculation and phosphate fertilization promoted benefits to the maize crop, indicating potential to increase yield.

The contribution of plant residues to the soil is an essential requirement for the success of no-tillage systems, especially in areas with a tropical climate where the organic material decomposition rate is high. The type of straw present on the soil surface can influence the culture implanted subsequently, mainly with regard to the availability of nitrogen (N). The objective of this study was to investigate the effect of cultural remains of maize (exclusive or intercropped with cover crops) on the development and productivity of the common bean grown in succession and fertilized with different N doses. The experimental design was a randomized block arranged in a factorial scheme (5 × 4), with four replications. The treatments consisted of combinations of cultural remains of exclusive maize, maize + Crotalaria spectabilis, maize + Cajanus cajan, maize + Canavalia ensiformis, and maize + Urochloa ruziziensis cultivated previously and of four N rates (0, 40, 80, and 120 kg ha-1) applied to bean crops. The plots consisted of seven lines of 7.5 m length with 0.45 m spacing between the lines. The evaluated parameters were: dry matter of the plant cover, dry matter of the aerial part (beans), production components, weight of 100 grains, and grain yield. The intercropping of maize and cover crops promoted an increase in dry matter over the soil, compared to the exclusive maize crop. There was an increase in the dry matter of bean plants with the increase in N rates in the two years of cultivation; regarding productivity, there was an increment only in the first year of cultivation. The maize consortium with cover plants provided adequate soil cover, but did not influence the productivity of beans cultivated in succession in the two years of cultivation.