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NASA NTRS · 20040112197

Evidence that elevated CO2 levels can indirectly increase rhizosphere denitrifier activity

Smart, D. R.·Ritchie, K.·Stark, J. M.·Bugbee, B.
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Abstract

We examined the influence of elevated CO2 concentration on denitrifier enzyme activity in wheat rhizoplanes by using controlled environments and solution culture techniques. Potential denitrification activity was from 3 to 24 times higher on roots that were grown under an elevated CO2 concentration of 1,000 micromoles of CO2 mol-1 than on roots grown under ambient levels of CO2. Nitrogen loss, as determined by a nitrogen mass balance, increased with elevated CO2 levels in the shoot environment and with a high NO3- concentration in the rooting zone. These results indicated that aerial CO2 concentration can play a role in rhizosphere denitrifier activity.

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NASA Discipline Life Support SystemsNon-NASA CenterTriticum/drug effects/growth & development/metabolismCarbon Dioxide/metabolism/pharmacologyPlant Roots/drug effects/growth & development/metabolism/microbiologyNitrates/pharmacologySupport, Non-U.S. Gov'tEnvironment, ControlledSoil MicrobiologyFertilizersCulture MediaComparative StudyAmmonia/metabolismSupport, U.S. Gov't, Non-P.H.SDose-Response Relationship, DrugHydroponicsNitrogen/metabolismPlant Shoots/drug effects/growth & development/metabolism

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Smart, D. R., Ritchie, K., Stark, J. M., Bugbee, B.. 1997-11-01. Evidence that elevated CO2 levels can indirectly increase rhizosphere denitrifier activity. https://ntrs.nasa.gov/citations/20040112197

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