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The vinasse is a by-product generated during the manufacture of alcohol from sugarcane fermentation. Rich in organic matter, it is known that the vinasse has the potential to be used as a source of nutrients for plants as well as microorganisms. In this study, the fungiPleurotus sajor-caju, P. ostreatus, P. albidusandP. flabellatuswere cultivated in vinasse and utilised as a complementary diet forDanio reriofish. The fungi mycelia cultured in vinasse for 15 days were lyophilised and offered to the fishes at a rate of 2% (medium/body weight) for 28 days.P. albidusproduced the highest biomass (16.27 g L−1). Bromatological analysis of mycelia showed similar values to commercial rations. Toxicity tests showed that fish survival was 100% and no significant biomass loss was observed, indicating that the tested fungi grown in vinasse showed no toxicity. Our results showed that vinasse is a promising by-product for fungal growth and the mycelia ofPleurotussp. fungi can be included in the diets of fish as a nutritional supplement. [ABSTRACT FROM AUTHOR]

Abstract: The effect of composted textile sludge on growth, nodulation and nitrogen fixation of soybean and cowpea was evaluated in a greenhouse experiment. The compost was incorporated into soil at 0, 9.5, 19 and 38tha−1 (bases upon the N requirement of the crops, i.e., 0, 50, 100 and 200kg available Nha−1). Growth, nodulation and shoot accumulation of nitrogen were evaluated 36 and 63 days after plant emergence. Nodule glutamine synthetase (GS) activity and leghemoglobin content were evaluated 63 days after emergence. Composted textile sludge did not show negative effects on nodule number and weight, nodule GS activity and leghemoglobin content. Nitrogen accumulation in shoot dry matter in soybean and cowpea was higher than other treatments with application of 19tha−1 of compost. Composting can be an alternate technology for the management of solid textile mill sludge. This study verifies that the composted textile sludge was not harmful to growth, nodulation and nitrogen fixation of soybean and cowpea. [Copyright &y& Elsevier]

Abstract: This laboratory study examines the effect of application of untreated and composted textile sludge on microbial biomass and activity in a Brazilian soil. The soil was amended with untreated and composted sludge at rates equivalent of 6.4tha−1 (0.64g per 100g of soil) and 19tha−1 (1.90g per 100g of soil), respectively, and were incubated at 28°C for 60days and daily sampled for microbial activity. An additional experiment, in the same condition, was conduced for evaluation of microbial biomass and enumeration of microorganisms at 15, 30 and 60days after incubation. The application of composted sludge increased significantly the microbial biomass and activity, and bacteria number of soil. There were not differences in the microbial activity and bacteria number among the control and untreated sludge amended soils. In conclusion, after 2months of incubation, the effects of the two amendments on soil microorganisms were: microbial biomass, soil respiration and bacteria number were increased only in composted sludge treated soil. qCO2 and fungi number were not affected by untreated and composted sludge. [Copyright &y& Elsevier]

Glyphosate [N-(phosphonomethyl)-glycine] is a broad-spectrum, non-selective, post-emergence herbicide that is widely used in agricultural. We studied, in vitro, changes in the microbial activity of typical Hapludult and Hapludox Brazilian soils, with and without applied glyphosate. Glyphosate was applied at a rate of 2.16 mg glyphosate kg−1 of soil and microbial activity was measured by soil respiration (evolution of CO2) and fluorescein diacetate (FDA) hydrolysis over a period of 32 days. We found an increase of 10–15% in the CO2 evolved and a 9–19% increase in FDA hydrolyses in the presence of glyphosate compared with the same type of soil which had never received glyphosate. Soil which had been exposed to glyphosate for several years had the strongest response in microbial activity. Most probable number (MPN) counts showed that after 32 days incubation the number of actinomycetes and fungi had increased while the number of bacteria showed a slight reduction. After the incubation period, high pressure liquid chromatography (HPLC) detected the glyphosate metabolite aminomethyl phosphonic acid (AMPA), indicating glyphosate degradation by soil microorganisms. [Copyright &y& Elsevier]

Abstract: The aim of this work was to investigate the response of soil microbial biomass and activity to practices in organic and conventional farming systems. The study was carried out at the Irrigation District of Piauí, Brazil. Five different plots planted with “acerola” orchard (Malpighia glaba) and established at the following management were evaluated: (1) under 12 months of soil conventional management (CNV); (2) under six months of soil organic management (ORG6); (3) under 12 months of soil organic management (ORG12); (4) under 18 months of soil organic management (ORG18); and (5) under 24 months of soil organic management (ORG24). Soil microbial biomass C (Cmic), basal respiration, organic carbon (Corg), Cmic-to-Corg ratio and metabolic quotient (qCO2) were evaluated in soil samples collected at 0–10cm depth. The highest Corg and Cmic levels occurred in organic system plots ORG18 and ORG24 compared to the conventional system. Soil respiration and Cmic-to-Corg ratio were significantly enhanced by the organic system plots. The qCO2 was greater in conventional than in organic system. These results indicate that the organic practices rapidly improved soil microbial characteristics and slowly increase soil organic C. [Copyright &y& Elsevier]