Productive characteristics of wheat according to nitrogen sources and levels

Nitrogen fertilization is an important management practice in grasses and quite complex, due to several factors which influence it, such as climatic conditions, cropping systems and available levels and sources. This study aimed at evaluating the effect of topdressing nitrogen (N) sources and levels on the productive characteristics of wheat (Triticum aestivum L.) grown after soybean, under no-till system. The experiment was conducted in an Oxisol, in Londrina, Paraná State, Brazil. The experimental design was randomized blocks, in a 3x4 factorial scheme, with four replications. As topdressing N sources, urea, urea + urease inhibitor (NBPT) and polymer-coated urea were evaluated, in 2008, and urea, urea + urease inhibitor (NBPT) and ammonium sulfate, in 2009, in four doses (0.0 kg ha-1, 40.0 kg ha-1, 80.0 kg ha-1 and 120.0 kg ha-1 of N) applied 20 days after emergence. Plant height, lodging percentage, mass of 1,000 grains, grain yield and hectoliter mass were determined, and results showed that increased topdressing N levels promoted plants lodging, decreasing the mass of 1,000 grains, yield and hectoliter mass. The N sources did not affect the yield of the BRS Pardela cultivar grown after soybean

Bookkeeping conventions and the micro-macro link

The formal accounting logic of the national accounts and other macroeconomic statistics is not always well understood. In addition, the relation between macro statistics and micro accounting data often is not clear. This paper starts out by summarizing the main bookkeeping conventions at the macro level. A distinction is made between vertical and horizontal double-entry bookkeeping, which, if applied simultaneously, result in quadruple-entry bookkeeping. Vertical bookkeeping refers to the double-entry bookkeeping used in business practice. Horizontal bookkeeping requires that the transactions and other economic relationships between agents answer strict consistency rules regarding valuation, timing, and classification. At the micro level, this consistency is not guaranteed. The article reviews three options to reinforce the micro-macro link (proposals by Nancy and Richard Ruggles, proposals by Harry Postner, and the intermediate accounts in France), and concludes with a few suggestions that could be used in the upcoming revisions of the international statistical manuals. Copyright 2004 Blackwell Publishing Ltd.