[-] Show simple item record

dc.contributor.advisorScharf, Peter C. (Peter Clifton), 1959-eng
dc.contributor.authorMedeiros, João A. S.eng
dc.date.issued2006eng
dc.date.submitted2006 Springeng
dc.descriptionThe entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file.eng
dc.descriptionTitle from title screen of research.pdf file viewed on (February 9, 2007)eng
dc.descriptionIncludes bibliographical references.eng
dc.descriptionThesis (M.S.) University of Missouri-Columbia 2006.eng
dc.descriptionDissertations, Academic -- University of Missouri--Columbia -- Agronomy.eng
dc.description.abstractTraditionally, urea has been incorporated to avoid losses of N by ammonia volatilization. However, this option is not available when topdressing wheat. The objective of this project is to evaluate several strategies designed to reduce the risk of ammonia volatilization loss from urea topdress applied on wheat. The tested strategies included treating urea with Agrotain (a urease inhibitor) or Agrotain + dicyandiamide (DCD), and use of coated urea products. Fertilizers were applied at a rate of 80 kg N ha-1. In 2004, wheat yields were low and none of the strategies designed to reduce N loss resulted in higher wheat yields with 95% confidence. However, the weather was favorable for ammonia volatilization and there was evidence from both yield and reflectance that urea + Agrotain + DCD was more effective than urea in delivering N to the crop. In 2005, urea + Agrotain, urea + Agrotain + DCD, and ammonium nitrateproduced higher yields when compared with broadcast urea. The addition of a timing effect for the 2005 experiment resulted in a significant and large yield response when treatments were applied in March compared to in January. Application of polymer- and gel-coated urea did not improve wheat yield relative to urea in either year. Agrotain + DCD was the most effective treatment for increasing yield and profitability from urea over the two study years.eng
dc.identifier.merlin.b5772099xeng
dc.identifier.otherMedeirosJ-050506-T3942eng
dc.identifier.urihttp://hdl.handle.net/10355/4533eng
dc.publisherUniversity of Missouri--Columbiaeng
dc.relation.ispartofcollectionUniversity of Missouri--Columbia. Graduate School. Theses and Dissertationseng
dc.subject.lcshUrea as fertilizereng
dc.subject.lcshCrops and nitrogeneng
dc.subject.lcshWheat -- Yieldseng
dc.titleManagement alternatives for urea use in corn and wheat productioneng
dc.typeThesiseng
thesis.degree.disciplineAgronomy (MU)eng
thesis.degree.grantorUniversity of Missouri--Columbiaeng
thesis.degree.levelMasterseng
thesis.degree.nameM.S.eng


Files in this item

[PDF]
[PDF]
[PDF]

This item appears in the following Collection(s)

[-] Show simple item record