Efficiency of urea application in fertigation of coffee trees irrigated by central pivot, using 15N tracer

• Grant number: 07/04525-0
• Support Opportunities: Regular Research Grants
• Start date: November 01, 2007
• End date: December 31, 2009
• Field of knowledge: Engineering - Nuclear Engineering - Applications of Radioisotopes
• Principal Investigator: Klaus Reichardt
• Grantee: Klaus Reichardt
• Host Institution: Centro de Energia Nuclear na Agricultura (CENA). Universidade de São Paulo (USP). Piracicaba , SP, Brazil

Abstract

The efficiency of nitrogen fertilization for the coffee crop is still notwell known under intensive and irrigated management conditions, when highrates are applied without much scientific support. Besides the cost/benefitproblem, these high fertilizer application rates can cause an undesiredenvironmental impact, which can be minimized through changes in managementpractices introduced by scientific knowledge. Employing the N-15 tracermethodology through labeled urea, this project aims to follow the fate offertilizer N within the soil-plant-atmosphere system, during one productivecycle of a coffee crop in plain production and representative in relationto soil-climate and intensive management under pivot irrigation.Information will be obtained on the sharing of the fertilizer N in thedifferent parts of the plant, shoot and root, also trying to quantifylosses, mainly those related to leaching and volatilization. Informationthat will be obtained are of high relevance for the Brazilian coffee cropindustry as a whole, but also for the State of São Paulo, to which most ofthe participants of this multidisciplinary project belong. (AU)