Effect of CO2 enrichment on carbon and nitrogen interaction in wheat and soybean

• Published in: Soil science and plant nutrition (Tokyo) 1997-12, Vol.43 (4), p.789-798
• Main Authors: Nakamura, T. (Hokkaido Univ., Sapporo (Japan). Faculty of Agriculture), Osaki, M, Koike, T, Hanba, Y.T, Wada, E, Tadano, T
• Format: Article
• Language: English
• Subjects: Agricultural and forest climatology and meteorology. Irrigation. Drainage; Agricultural and forest meteorology; Agronomy. Soil science and plant productions; AZOTE; Biological and medical sciences; CARBON; CARBON DIOXIDE; carbon isotope discrimination; carbon-nitrogen interaction; CARBONE; CARBONO; Climatic adaptation. Acclimatization; crop growth rate; DIOXIDO DE CARBONO; DIOXYDE DE CARBONE; Economic plant physiology; enrichment; FOTOSINTESIS; Fundamental and applied biological sciences. Psychology; General agronomy. Plant production; GLYCINE MAX; Mineral nutrition; Net assimilation, photosynthesis, carbon metabolism. Photorespiration, respiration, fermentation (anoxia, hypoxia); NITROGEN; Nitrogen metabolism and other ones (excepting carbon metabolism); NITROGENO; Nutrition. Photosynthesis. Respiration. Metabolism; PHOTOSYNTHESE; PHOTOSYNTHESIS; TRITICUM AESTIVUM
• ISSN: 0038-0768; 1747-0765
• DOI: 10.1080/00380768.1997.10414645

Effect of CO2 enrichment on the carbon-nitrogen balance in whole plant and the acclimation of photosynthesis was studied in wheat and soybean with a combination of two nitrogen application rates and two temperature treatments. Results were as follows: 1. Carbon (dry matter)-nitrogen balance of whole plant throughout growth was remarkably different between wheat and soybean, as follows: 1) in wheat, the relationship between the amount of dry matter (DMt) and amount of nitrogen absorbed (Nt) in whole plant was expressed by an exponential regression, in which the regression coefficient was affected by only the nitrogen application rate, and not by CO2 and temperature treatments, and 2) in soybean the DMt-Nt relationship was basically expressed by a linear regression, in which the regression coefficient was only slightly affected by the nitrogen treatment. Thus, carbon-nitrogen interaction in wheat was strongly affected by the underground environment, but not by the above ground environment, while that in soybean was less affected by both under and above ground environments. 2. The photosynthetic response curve to CO2 concentration in wheat and soybean was loss affected by the CO2 enrichment treatment, while that in wheat and soybean was affected by the nitrogen treatment, indicating that nitrogen nutrition is a more important factor for the regulation of photosynthesis regardless of the CO2 enrichment. 3. Carbon isotope discrimination (Delta) in soybean was similar to that in wheat under ambient CO2, while lower than that in wheat under CO2 enrichment, suggesting that the carbon metabolism is considerably different between wheat and soybean under the CO2 enrichment conditions