Phosphorus

This paper presents the effect of hydric stress on Select sunflower hybrid grown under near-neutral and acid soil conditions. The experiment was conducted in green - house with sunflower plants grown in PVC tubs filled with: near- neutral soil (pH = 6.2 ) (I), acid soil (pH = 5.27) (II) and ferti-lized acid soil ((phosphorus (100 kg/ha), potassium (100 kg/ha)

We have developed a modified physical vapor transport (M-PVT) growth technique for the preparation of SiC single crystals which makes use of an additional gas pipe in order to control the gas phase composition of the conventional physical vapor transport (PVT) configuration. We discuss ...

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Growth kinetics of Thiobacillus ferrooxidans in batch cultures, containing prills of elementary sulfur as the sole energy source, were studied by measuring the incorporation of radioactive phosphorus in free and adsorbed bacteria. The data obtained indicate an initial exponential growth of the attached bacteria until saturation of the susceptible surface was reached, followed by a linear release of free bacteria due to successive replication of a constant number of adsorbed bacteria. These adsorbed bacteria could continue replication provided the colonized prills were transferred to fresh medium each time the stationary phase was reached. The bacteria released from the prills were unable to multiply, and in the medium employed they lost viability with a half-life of 3.5 days. The spreading of the progeny on the surface was followed by staining the bacteria on the prills with crystal violet; this spreading was not uniform but seemed to proceed through distortions present in the surfa...

We present experimental laboratory evidence and field observations of an autocatalyzed, programmed cell death (PCD) pathway in the nitrogen-fixing cyanobacteriumTrichodesmium spp., which forms massive blooms in the subtropical and tropical oceans. The PCD pathway was induced in response to phosphorus and iron starvation as well as high irradiance and oxidative stress. Transmission electron microscopy revealed morpho- logical degradation of internal

Nitrogen (N) and phosphorus (P) and N: P ratio in terrestrial plants and the patterns at a large geographical scale are an important issue in ecological stoichiometry. In particular, it is essential to know that for a single species, how the N: P stoichiometry varies with climatic ...

The importance of comets for the origin of life on Earth has been advocated for many decades. Amino acids are key ingredients in chemistry, leading to life as we know it. Many primitive meteorites contain amino acids, and it is generally believed that these are formed by aqueous alterations. In the collector aerogel and foil samples of the Stardust mission after the flyby at comet Wild 2, the simplest form of amino acids, glycine, has been found together with precursor molecules methylamine and ethylamine. Because of contamination issues of the samples, a cometary origin was deduced from the (13)C isotopic signature. We report the presence of volatile glycine accompanied by methylamine and ethylamine in the coma of 67P/Churyumov-Gerasimenko measured by the ROSINA (Rosetta Orbiter Spectrometer for Ion and Neutral Analysis) mass spectrometer, confirming the Stardust results. Together with the detection of phosphorus and a multitude of organic molecules, this result demonstrates that c...

Abstract. The magnitude of root competition 17 year-old coconut palms suffer from three year-old inter-planted multipurpose trees, Vateria indica L., Ailanthus triphysa (Dennst.) Alston. or Grevillea robusta A. Cunn. and kacholam (Kaempferia galanga L.), a ...

BackgroundIn cattle, diseases of abomasum are of great importance and include right and left displacement, torsion, impaction, pyloric stenosis and ulceration. Displacement of the abomasum has become one of the most important metabolic and organic internal disorders of cattle and the disease is most prevalent in high performing milk breeds. Abomasal displacement occurs most frequently in high yielding cows during early lactation. It has been reported that feeding a large amount of concentrations or corn silage to dairy cows inhibits the motility of the resulting in gas accumulation followed by dilation and atony and thereby causing bovine displaced. Abomasal displacement, ketosis, parturient paresis, retain placenta and endometritis has been often associated with a fatty liver.AimsThis investigation was undertaken to determine the relationship of abomasal displacement and fatty liver syndrome in dairy cows.Methodsthis study, twelve cows with abomasal displacement (7 RDA, 5 LDA) and 10 ...

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