N2O emission in relation to plant and soil properties and yield of rice varieties

• Published in: Agronomy for sustainable development 2010-12, Vol.30 (4), p.733-742
• Main Authors: Baruah, K. K., Gogoi, B., Gogoi, P., Gupta, P. K.
• Format: Article
• Language: English
• Subjects: Agricultural sciences; Agriculture; Agronomy. Soil science and plant productions; Biological and medical sciences; Biomedical and Life Sciences; Ecology, environment; Fundamental and applied biological sciences. Psychology; Life Sciences; Research Article; Soil Science & Conservation; Sustainable Development
• ISSN: 1774-0746; 1773-0155
• DOI: 10.1051/agro/2010021

Nitrous oxide (N 2 O) is a major greenhouse gas contributing to global warming. Rainfed rice fields are considered to be a notable source of atmospheric N 2 O emission. To investigate the dynamics of N 2 O emission and the relationship of plant and soil properties with emission of N 2 O in rice, a field experiment was conducted. The five popularly grown rice varieties Luit, Disang, Kapilli, Siana and Phorma were grown in the fall season under rainfed conditions. N 2 O emission was measured at seven-day intervals starting from the day of transplanting for the whole crop growing season. We also measured soil parameters, e.g. soil pH, soil temperature, soil organic carbon, soil NO 3 − -N, and field water level; and plant growth parameters: root-shoot dry weight, root length and leaf area. Our results show that N 2 O emission from the plant varieties ranged from 1.24 μg to 379.40 μg N 2 O−N m −2 h −1 . Seasonal N 2 O emission from the rice varieties ranged from 77 to 150 mg N 2 O−N m −2 . Root dry weight, shoot dry weight, soil NO 3 − -N, root length, leaf area and field water showed relationships with N 2 O emission. Root and shoot weight, soil NO 3 − -N and field water were found to be the main factors influencing N 2 O emission. The varieties Phorma and Siana, with lower grain productivity but profuse vegetative growth, showed higher seasonal N 2 O emission.