Nitrous oxide emissions from native oaxacan maize and mucilage effects on US maize soil

Native maize and US Z37 hybrid maize were grown under greenhouse conditions for nine weeks and measured for N2O and CO2 emissions weekly. Native maize cultivars showed increased nitrous oxide emissions compared to US maize two weeks after a fertilizer application at the equivalent of 30 kg/ha. These results suggest that native maize is changing the rhizosphere and causing the rates of nitrification or denitrification to change in response to fertilizer treatment. Mucilage produced by maize cultivars was added to soils of native, US, and control soils to test the effects of mucilage on N2O and CO2 emissions, nitrate, nitrite, and ammonium. Mucilage was found to increase carbon dioxide emissions from soil. This suggests that native maize mucilage increases microbial activity in these soils. Also, the US soil showed a peak of nitrous oxide emissions when mucilage was added suggesting maize mucilage leads to specific microbial activity in the soil increasing rates of nitrification, denitrification, or a combination of these processes. These results support the idea that these native maize cultivars are using this mucilage to change rates of nitrification so that more nitrogen is available for growth.