abstract in order to evaluate the effect of different nitrogen application methods on yield and yield components of winter wheat, a field experiment with split plot arrangement in completely randomized blocks design with four replicates was conducted in 2006. basal dressing in three levels (1- with no basal dressing, 2- strip and 3- distributing nitrogen fertilizer) as main plot and top dressin...

Coastal aquaculture can contribute to eutrophication of receiving waters. New technologies and improved management practices allow the aquaculture industry to be more sustainable and economically viable. Current practices, however, do not provide an additional use for effluent water. Nitrogen, phosphorus and other effluent compounds could be valuable plant nutrients. Inflow and effluent water f...

this research has been done for studying the effect of split application of nitrogen fertilizer on growth indexes and yield of three hybrids of grain corn in shahrood. a split plot experiment based on randomized complete block design with four replications was carried out in 2007. three hybrids of corn (double cross 370, single cross 447, single cross 499) were placed in main plots and split ap...

A consideration of fertilizer materials furnishing the three' major plant foods reveals the fact that sources of phosphoric acid and potash have remained almost constant while the sources of nitrogen have undergone decided changes. Superphosphate has been, and probably will continue to be, our main source of phosphoric acid in most fertilizer mixtures. In the year 1900, 79.8 per cent. of the to...

Nitrogen is the most important essential nutrient that plays a major role in achieving maximum crop yield in agriculture. Therefore, nitrogen fertilizers such as ammonium sulfate and urea have been extensively used in modern agriculture. These fertilizers are generally oxidized to nitrate via nitrite by nitrifying microorganisms in the agricultural field (4, 10, 11). The serious environmental p...

The use of N fertilizer in agriculture is a major source of Nitrous Oxide, an important greenhouse gases. Market-based instruments, such as incentives or taxes, may help reduce Nitrous Oxide emission by changing Nitrogen application rate. Using a dynamic programming approach, we found that changing corn price or fertilizer price have effects on both farm profit and Nitrogen application rate. Ho...

Vegetables have a relatively high nitrogen requirement and at times growers apply too much fertilizer-N that contributes to ground and surface water pollution. Fertilization can be made more efficient by plant analysis. Plant tissue (petiole) nitrate testing is a way of monitoring the nitrogen condition of the crop during the growing season. This is an especially useful method as the petiole is...

A field experiment was carried out at the Didactic and Experimental Farm in Swadzim near Poznań in 2004-07. Two maize cultivars were studied, six nitrogen doses and magnesium doses. The effects of the mentioned factors exerted on the utilization of nitrogen from the applied mineral fertilizer and on the nitrogen harvest index were studied. The impact of nitrogen fertilization on the mineral int...

The Haber–Bosch process for the commercial production of ammonia demonstrated in 1913 was a watershed event in the mass production of urea, the principal nitrogen fertilizer for modern agriculture. Today, thanks to the so-called “green revolution” starting in in the 1960s, nearly half of the world population relies on increased crop yields, through the use of nitrogen fertilizers, to access aff...