The Response of Nitrifying Bacteria to Treatments of N-Serve and Roundup in Continuous-Flow Soil Columns
Abstract
This study examined the effects of Roundup (N-(phosphonomethyl) glycine) and N-Serve (2-chloro-6-(trichloromethyl) pyridine) on nitrifying organisms in static batch, perfusion soil columns, and a new continuous-flow soil column system. Both N-Serve and Roundup were shown to significantly inhibit nitrification in treated soils over untreated controls. N-Serve completely inhibited nitrification at concentrations greater than 42 micrograms nitrapyrin g-1 dry soil. Roundup significantly reduced nitrification at 6.8 and 68mg glyphosate g-1 dry soil. Continuous-flow columns were examined to determine if microbial populations were altered by chemical treatment. Concentrations of 4.2 mg nitrapyrin and 68 mg glyphosate g-1 dry soil significantly increased heterotrophic populations. Numbers of heterotrophs were not significantly different from controls in soils at lower concentration. Numbers of nitrifying bacteria did not appear to change following treatment although nitrification was inhibited. Fluorescent antibody analysis of nitrifiers revealed that Nitrosolobus was more numerous than Nitrosospira and Nitrosomonas. Nitrosolobus increased in number whereas the other two genera remained unchanged. In this study, the continuous-flow system proved to be both reliable and useful in the culture of nitrifying bacteria. This method is an alternative to traditional techniques for evaluation of the effects of chemicals on microbial biogeochemical cycles. Keywords: Theses; Xenobiotic compounds.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 15, 1988
- Accession Number
- ADA208452
Entities
People
- Albert N. Rhodes
Organizations
- Air Force Institute of Technology