Biological formulations used as inoculants are increasingly present in grasses, especially in corn. Positive results in promoting plant growth, with different associations with diazotrophic bacteria, show these capacities of interaction to act as plant growth regulators, making it a promising alternative with a low environmental impact. Thus, this study aimed to evaluate the efficiency of inoculation and co-inoculation of nodulating and non-nodulating diazotrophic bacteria as promoters of initial growth in corn plants. Therefore, the bacteria Azospirillum brasilense (UFG21 strain), Bradyrhizobium japonicum (commercial product), and their co-inoculation were used in seed treatment. The evaluations consisted of growth measuring of the root system and shoot and evaluating leaf chlorophyll concentration. The results showed a beneficial interaction between the bacteria and the corn plant, with an increase in the root system and chlorophyll content, compared to the control treatment.

Sweet corn is susceptible to the attack of various pathogens that affect its metabolism and compromise its quality and production. This study aimed to identify the causal agent of stem rot in sweet corn plants under greenhouse conditions. The identity of the pathogenic isolate was confirmed by sequencing of internal transcribed spacer (ITS1/ITS4), beta-tubulin (BT2A/BT2B), calmodulin (CL1/CL2) and translation elongation factor 1α (TEF1). The morphological and sequencing characteristics showed that Fusarium sacchari, which belongs to the Fusarium fujikuroi complex, is directly associated with the symptoms observed in the field. This fungal isolate has never been associated with diseases in Zea mays (saccharata group) in Brazil; therefore, this is the first report of the fungus infecting sweet corn in a cultivated area.

This study survey and analyze the evolution of the main normative instruments for environmental protection in Brazil. The research showed that the environmental protection models in Brazil developed as ecological awareness and control over environmental issues became relevant points. In this sense, environmental degradation, especially of soils, is a concern that has always been under discussion in Brazil. As can be seen, over the years, the Brazilian legislation has sought mechanisms to improve the formulation of more efficient normative instruments. RESUMOEste estudo faz o levantamento e analisa a evolução dos principais instrumentos normativos para a protecção ambiental no Brasil. A investigação mostrou que os modelos de protecção ambiental no Brasil se desenvolveram como consciência ecológica e controlo sobre questões ambientais tornaram-se pontos relevantes. Neste sentido, a degradação ambiental, especialmente dos solos, é uma preocupação que tem estado sempre em discussão no Brasil. Como se pode ver, ao longo dos anos, a legislação brasileira tem procurado mecanismos para melhorar a formulação de instrumentos normativos mais eficientes.

Chemical control of sugarcane red rot, caused by Colletotrichum falcatum, forms part of integrated management of the disease. A rapid microtiter bioassay based on the colorimetric changes of resazurin dye was developed to evaluate the sensitivity of C. falcatum to the main chemical fungicide groups, including strobilurin, triazole, benzimidazole, isophthalonitrile and dithiocarbamate. There was no significant difference among the isolates in terms of growth inhibition for any of the active ingredients tested (α = 0.01). The C. falcatum isolates showed almost similar sensitivity to various fungicides. The active ingredients varied in relation to fungitoxicity. Doses that inhibited 50% of C. falcatum growth were calculated as a percentage of resazurin reduction due to various fungicides. The colorimetric method used to assess the fungitoxicity of active ingredients to C. falcatum, combined with resazurin, proved a fast practical and efficient method. © 2022 Friends Science Publishers

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