Wednesday, November 7, 2007
292-7

Effect of Slow Release Nitrogen Fertilizer on Soil Quality -Soil Microbial Population.

Jorge Hernandez, Plant Soil and Ag Systems, Southern Illinois University, 1205 Lincoln Drive, Carbondale, IL 62901, Rosalia Garcia, Utrecht University, Othellodreef 9, Utrecht, Netherlands, and David Lightfood, Plant Soils and Ag Systems, Southern Illinois University, 1205 Lincoln Drive, Carbondale, IL 62901.

Enhanced release nitrogen fertilizers or slow release fertilizers are used to augment nitrogen use efficiency; it needs to be degraded into soluble nitrogen compounds, by a specific microbial catalyzed reaction. The objectives of this study are to compare different techniques of total soil DNA isolation, in the DNA quality and purity produced, to isolate a bacterium capable of methylene urea degradation and to studythe soil community shift pattern using Shannon indexes and the Dice coefficient after applying urea and methylene urea. Urea and methylene-urea-triazone were incorporated into the soil. DNA was extracted. Denaturant gradient gel electrophoresis was performed with the PCR amplicons. Shannon Wiener Index was determined by bands. A significantly greater biological diversity was observed in the sample group with methylene-urea-triazone. There was a difference between urea and the enhanced efficiency fertilizer in plant response and bacterial diversity. Microorganisms in soil need time to respond to environmental changes.