Publication Date
1993
Description
Plant growth, total nitrogenase activity and hydrogen evolution rates were determined for 39-, 47- and 54-day-old white clover (Trifo/ium repe11s L.) plants growing at 350 or 700 ppm CO2 with day/night temperatures of 18/13°C or 28/23°C. The three plant parameters increased with plant age, temperature and CO2 concentration. Nitrogenase activity/g plant dry matter (DM) and hydrogen evolved/ g DM decreased as plants developed, presumably as nitrogen was cycled internally and plants became less reliant on recently fixed nitrogen. Nodule relative efficiency - an expression of the energy flux to nitrogenase relative to hydrogen production - was significantly lower initially in plants grown at 700 ppm CO2 and l8/13°C, but otherwise did not vary between treatments, It is proposed that legumebased agriculture will contribute more ozone-damaging hydrogen to the stratosphere under future atmospheric CO2 levels and that the efficiency of nitrogen fixation will be reduced at lower temperatures.
Citation
Crush, J R.; Campbell, B D.; and Evans, J.P M., "Effect of Elevated Atmospheric Carbon Dioxide Levels on Nodule Relative Efficiency in White Clover" (2024). IGC Proceedings (1993-2023). 10.
https://uknowledge.uky.edu/igc/1993/session30/10
Included in
Agricultural Science Commons, Agronomy and Crop Sciences Commons, Plant Biology Commons, Plant Pathology Commons, Soil Science Commons, Weed Science Commons
Effect of Elevated Atmospheric Carbon Dioxide Levels on Nodule Relative Efficiency in White Clover
Plant growth, total nitrogenase activity and hydrogen evolution rates were determined for 39-, 47- and 54-day-old white clover (Trifo/ium repe11s L.) plants growing at 350 or 700 ppm CO2 with day/night temperatures of 18/13°C or 28/23°C. The three plant parameters increased with plant age, temperature and CO2 concentration. Nitrogenase activity/g plant dry matter (DM) and hydrogen evolved/ g DM decreased as plants developed, presumably as nitrogen was cycled internally and plants became less reliant on recently fixed nitrogen. Nodule relative efficiency - an expression of the energy flux to nitrogenase relative to hydrogen production - was significantly lower initially in plants grown at 700 ppm CO2 and l8/13°C, but otherwise did not vary between treatments, It is proposed that legumebased agriculture will contribute more ozone-damaging hydrogen to the stratosphere under future atmospheric CO2 levels and that the efficiency of nitrogen fixation will be reduced at lower temperatures.
