RESUMO

A cana-de-açúcar pode ser empregada na alimentação animal devido ao seu alto rendimento de matéria seca. No entanto, há muitas recomendações para evitar o emprego como alimento para animais de bom potencial genético, pois apresenta baixo teor proteico e de minerais, bem como e fibra de baixa qualidade. Desta forma, o objetivo deste trabalho foi avaliar os efeitos da aplicação de uma mistura de cinco bactérias diazotróficas (Gluconacetobacter diazotrophicus; Herbaspirillum seropedicae; Herbaspirillum rubrisubalbicans; Paraburkholderia tropica; Nitrospirillum amazonense) e da adubação nitrogenada sobre a produção, maturação e composição químico-bromatológica de cinco variedades de cana-de-açúcar com potencial para serem empregadas na alimentação animal. Os tratamentos foram formados conforme a combinação dos cinco genótipos de cana-de-açúcar (RB867515, RB966928, RB106814, RB106818 e RB106819) com quatro condições de inoculação e adubação nitrogenada em cobertura. Os teores de sólidos solúveis totais foram determinados dos 180 dias após o transplante até a colheita do experimento, onde foi avaliada a produtividade e a amostragem de material foi coletada para as avaliações químico-bromatológicas: matéria seca, nitrogênio acumulado, proteína bruta, fibra em detergente neutro, fibra em detergente ácido, holocelulose, celulose, hemicelulose, lignina, extrativos totais e cinzas. De acordo com os resultados deste estudo, conclui-se que a aplicação de bactérias diazotróficas de forma isolada ou em conjunto com a adubação nitrogenada, aumenta a produtividade e os sólidos solúveis totais, antecipando a maturação, além de melhorar a composição químico-bromatológica das plantas de cana-de-açúcar.

Sugarcane can be used in animal feed due to its high dry matter yield. However, there are many recommendations to avoid its use as food for animals with good genetic potential, since it has a low contents of protein and minerals, as well as fiber of low quality. Therefore, this work aimed to evaluate the effects of applying a mixture of five diazotrophic bacteria (Gluconacetobacter diazotrophicus; Herbaspirillum seropedicae; Herbaspirillum rubrisubalbicans; Paraburkholderia tropica; Nitrospirillum amazonense) and nitrogen fertilization on the production, maturation, and chemical-bromatological composition of five sugarcane varieties with potential to be used in animal feed. The treatments were formed according to the combination of the five sugarcane genotypes (RB867515, RB966928, RB106814, RB106818, and RB106819) with four conditions of inoculation and nitrogen fertilization in coverage. The levels of total soluble solids were determined from 180 days after transplantation until the harvest of the experiment, where productivity was evaluated and the sample material was collected for chemical-bromatological evaluations: dry matter, accumulated nitrogen, crude protein, neutral detergent fiber, acid detergent fiber, holocellulose, cellulose, hemicellulose, lignin, total extracts, and ashes. According to the results of the present study, it is concluded that the application of diazotrophic bacteria alone or in conjunction with nitrogen fertilization, increases productivity and total soluble solids, anticipating maturation, in addition to improving the chemical-bromatological composition of sugarcane plants.

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RESUMO

This work deals with the durability of a Pinus elliotti wood impregnated with alumina (Al2O3) particles. The samples were impregnated at three different Al2O3 weight fractions (c.a. 0.1%, 0.3% and 0.5%) and were then exposed to two wood-rot fungi, namely white-rot fungus (Trametes versicolor) and brown-rot fungus (Gloeophyllum trabeum). Thermal and chemical characteristics were evaluated by Fourier transform infrared spectroscopy (FT-IR) and thermogravimetric (TG) analyses. The wood which incorporated 0.3 wt% of Al2O3 presented a weight loss 91.5% smaller than the untreated wood after being exposed to the white-rot fungus. On the other hand, the highest effectiveness against the brown-rot fungus was reached by the wood treated with 5 wt% of Al2O3, which presented a mass loss 91.6% smaller than that of the untreated pine wood. The Al2O3-treated woods presented higher antifungal resistances than the untreated ones in a way that: the higher the Al2O3 content, the higher the thermal stability. In general, the impregnation of the Al2O3 particles seems to be a promising treatment for wood protection against both studied wood-rot fungi. Additionally, both FT-IR and TG results were valuable tools to ascertain chemical changes ascribed to fungal decay.