Source, Rate, and Time of Nitrogen Fertilization for Sugarcane

The requirement for worldwide abundant food, feed, fiber, and more recently biofuel, leads to higher amounts of fertilizer utilized in agriculture in diverse parts of the globe. Nitrogen (N) is, most generally, the first nutrient in terms of plant demand. Nitrogen promotes rapid growth, increases leaf size and quality, hastens crop maturity, and promotes fruit and seed development. Because nitrogen is a constituent of amino acids, which are required to synthesize proteins and other related compounds, it plays a role in almost all plant metabolic processes. Nitrogen is an integral part of chlorophyll manufacture through photosynthesis. Carbohydrates (sugars) provide energy required for growth and development Nitrogen application may be interfered by chemical reactions generating losses by leaching or volatilization, therefore the use of distinct sources is strategic to overcome such problems. In many areas farmers are testing different sources to increase N use efficiency.The main objective of the study will be to evaluate the agronomic effectiveness of different N sources for sugar cane. Also, it will be possible to study other important factors which affect the N fertilizer effectiveness in tropical soils.

IPNI-2013-BRA-62

25 Mar 2014

2013 Annual Interpretive Summary


The main objective of the study is to evaluate the agronomic effectiveness of different N fertilizer sources for sugar cane. Other important factors that affect the effectiveness of N fertilizer in tropical soils, such as rate and time of application will also be studied. Three sources (UAN, Urea and Ammonium Sulfate), three rates of N (60, 120 and 180 kg N/ha), two times of application (100% at plant emergence versus 50% at plant emergence plus 50% when plant reaches a height of 60 cm), and two control treatments (zero N and 120 kg N/ha as Ammonium Sulfate) were used in different treatment combinations. The field trial was initiated in October 2013, but an unfortunate event jeopardized the trial in December. Decision was taken to start a new trial in March or April of 2014 and keep the first one under evaluation until the first harvest.