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201.
Tropical Animal Health and Production - We aimed to evaluate the chemical composition, production yield, and economic viability of Minas Frescal cheese produced with milk from buffaloes...  相似文献   
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The amount and composition of crop residues added to soil in agroecosystems can influence decomposition processes and soil organic matter levels. This study aimed to evaluate residues (quantity and quality) of different corn cultivars commonly used in Brazilian cropping systems. The experiment was conducted for two seasons (2005/2006 and 2006/2007) in Rolândia, Paraná State, Brazil. Ten corn cultivars that represent five degrees of breeding development (i.e., landrace, commercial variety, double cross, triple cross, and single cross hybrids) were evaluated. At harvest, carbon (C) and nitrogen (N) of non-yield residue and grain were determined. Except for grain C, other measures (grain N concentration, residue C and N concentration, and C:N ratio) varied among cultivars. In general, the hybrids had higher residue C and lower residue N concentrations than the landraces and commercial varieties. Findings suggest that breeding selection may have altered residue production and composition, which may influence soil C dynamics.  相似文献   
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Abstract

Biofortification of soybean grains with lithium (Li) is a strategy to improve a food with high social acceptance, in order to promote health benefits. The aim of this work was to evaluate the development of plants and the production of biofortified soybeans with two Li sources. The experiment was conducted in a completely randomized design with five replicates. Ten treatments were obtained in a 2x5 factorial scheme, comprising two sources of Li (LiOH - Li hydroxide and Li2SO4 - Li sulfate) and five doses (0, 30, 60, 90 and 120?mg kg?1) in stages V4 and R1. The supply of Li promoted significant effects (p?≤?0.05) on the morphology, yield components and nutritional status of soybean plants. The highest grain yield was obtained with the use of Li2SO4 at the estimated dose of 45.7?mg kg?1. The plants accumulated Li between 8.00 and 11.20?mg kg ?1, respectively, with the use of Li2SO4 and LiOH. In the grains, the highest concentrations of Li were obtained with the application of 120?mg kg?1. Li2SO4 and LiOH are good sources for biofortification of soybean grains.  相似文献   
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The effects of cadmium (Cd) exposure on sunflower (Helianthus annuus L.) nutrient accumulation remain unclear. However, studies concerning crop improvement for Cd tolerance suggest the use of biotechnology techniques such as tissue culture. It is still unknown whether in vitro cells respond to Cd exposure in a way similar to plants. In this paper, the objectives were (1) to characterize the effects of Cd exposure in macronutrient and micronutrient accumulation in different sunflower organs/tissues and (2) to compare the behavior of two culture systems (plants vs. tissue culture) regarding Cd and nutrient accumulation. To achieve these aims, sunflower plants were grown hydroponically in the presence of Cd (at levels of 0, 5, 50, and 500 μ M). For in vitro cultures, seeds were germinated axenically and leaf explants were then grown on Murashige and Skoog medium (MS). One-month-old calluses were grown on MS medium containing 0, 5, 50, and 500 μ M Cd. After 21 d of exposure to 500 μ M, all plants were dead. The contents of macro- and micronutrients and of Cd were determined by ICPS in 18 d-exposed plants and calluses and in calluses exposed for six months to 50 μ M Cd. At day 18, Cd content increased in leaves, roots, and calluses. Cadmium exposure also decreased the contents of magnesium (Mg), calcium (Ca), iron (Fe), and manganese (Mn) in roots and of Mg, Ca, copper (Cu), Fe, and Mn in shoots. Exposed calluses suffered decreases only in Mg, Ca, and Mn contents. The contents of most of these nutrients in six-month-exposed calluses were similar to those of the control calluses, indicating that these long-term exposed in vitro cells developed mechanisms for regulating the effects of Cd on the accumulation of nutrients.  相似文献   
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This work was performed in the Rio de Janeiro State, Brazil, with the objective to evaluate the nutritional status of yellow passion fruit plants along different phenological stages, using the DRIS method. Fifty-four passion fruit cultivated areas with an annual yield productivity ranging from 6.95 to 33.8 t ha?1 year?1 and average productivity of 16.9 t ha?1 year?1 were selected in the region. The contents of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), sulfur (S), chlorine (Cl), iron (Fe), zinc (Zn), manganese (Mn), and boron (B) were evaluated. The reference standards were established (mean and variation coefficient) for the values of the nutrient concentration ratios, two by two, on samples from high yield productivity plantations and analyzed by the DRIS index of nutrients for the medium and low yield productivity areas. The established standards differed according with the phenological stage of the culture. In a general way, the mean content of the evaluated nutrients did not differed between the two productivity levels into each phonological stage. There was a difference for the Nutritional Limitation Order between different phenological stages of yellow passion fruit plants. The most negative DRIS indexes and the highest absolute values for the Average Nutritional Balance on yellow passion fruit plants in the region, were found for potassium in May, phosphorus in October and iron in January.  相似文献   
208.
Journal of Plant Diseases and Protection - This study aimed to investigate the effects of the essential oils of Cymbopogon flexuosus and Alpinia zerumbet in the treatment of cowpea [Vigna...  相似文献   
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Owing to the increasing importance of aquaculture to compensate for the progressive worldwide reduction of natural fish and to the fact that several fish farming plants often suffer from heavy financial losses due to the development of infections caused by microbial pathogens, including multidrug resistant bacteria, more environmentally-friendly strategies to control fish infections are urgently needed to make the aquaculture industry more sustainable. The aim of this review is to briefly present the typical fish farming diseases and their threats and discuss the present state of chemotherapy to inactivate microorganisms in fish farming plants as well as to examine the new environmentally friendly approaches to control fish infection namely phage therapy and photodynamic antimicrobial therapy.  相似文献   
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