|Lerch, Robert - Bob|
Submitted to: ASA-CSSA-SSSA Annual Meeting Abstracts
Publication Type: Abstract only
Publication Acceptance Date: 11/20/2007
Publication Date: 11/20/2007
Citation: Lin, C.H., Goyne, K.W., Kremer, R.J., Lerch, R.N., Garrett, H.E. 2007. Rhizodegradation of sulfamethazine and tetracycline and the associated impacts on soil microbial activities [abstract]. ASA-CSSA-SSSA Annual Meeting Abstracts. ASA-CSSA-SSSA Annual Meeting. Nov. 4-8, 2007, New Orleans, LA. 2007 CD ROM. Interpretive Summary:
Technical Abstract: The use of sulfamethazine and tetracycline to maintain animal health in the swine, poultry and cattle feedlots operations results in significant application of these veterinary pharmaceuticals to the landscape during grazing or manure disposal operations. Drinking water sources contaminated by these veterinary antibiotics have raised public health concern in Southwestern Missouri and other regions of the US. Recent studies have demonstrated the benefits of using multi-species vegetated buffers to reduce the transport of veterinary antibiotics. However, the fate of these antibiotics in vegetative buffers, and their impact on rhizosphere microbial activities have not been well documented. A growth chamber study was conducted to investigate the rhizodegradation of 3H-sulfamethazine and 3H-tetracycline and the relationship of degradation with soil enzyme activities in the rhizosphere of four selected plant species. The plant species included: 1) switchgrass, 2) eastern gammagrass, 3) orchardgrass, 4) hybrid poplar. All plant treatments were grown in pots containing Mexico silt loam. Pots containing soil without plants were used as controls. Plants were grown to maturity (~3 months), and the rhizosphere soils were collected. Radio-labeled sulfamethazine or tetracycline was then applied to the rhizosphere soil and incubated in the dark for 100 days. The developed knowledge will help us understanding the fate of these two antibiotics and their associated interaction with soil microbial activities. Moreover, the grass species showing high rhizodegradation potential could be incorporated into buffer designs to mitigate the impacts of these two antibiotics in the environment.