[Effects of free-air CO2 enrichment on nitrogen uptake and utilization of wheat].
In this paper, the effects of free-air CO2 enrichment (FACE) and its interaction with nitrogen supply on the nitrogen content, uptake, allocation, and use efficiency of winter wheat variety Ningmai 9 at its different growth stages were studied in 2001-2003. The results showed that under FACE treatment, the nitrogen content in wheat plant sampled at different growth stages all decreased significantly, with an average decrement of 4.4% to 13.4% compared with the control. The nitrogen accumulation under FACE increased significantly (9.2% -32.3%), and the increasing rate was larger at middle growth stage than at early and late growth stages. Nitrogen fraction was higher in stem, but lower in leaf. As for spike, the accumulation of nitrogen depended on the growth stage. FACE resulted in a significant increase (5.5% -10.3%) of nitrogen use efficiency for biomass production at all growth stages, of nitrogen harvest index (16.3%) at maturing stage, and of nitrogen use efficiency (9.3%) for grain yield. Nitrogen application increased the nitrogen content of wheat plant and its N uptake at all growth stages, decreased the nitrogen use efficiency, but had less effect on the nitrogen allocation in different organs.
Yang
Lian-Xin
LX
Key Laboratory of Crop Genetics & Physiology of Jiangsu Province, Yangzhou University, Yangzhou 225009, Jiangsu, China. lxyang@yzu.edu.cn
Huang
Jian-Ye
JY
Li
Shi-Feng
SF
Yang
Hong-Jian
HJ
Zhu
Jian-Guo
JG
Dong
Gui-Chun
GC
Liu
Hong-Jiang
HJ
Wang
Yu-Long
YL
D000388:Air / Q000032:analysis; D002245:Carbon Dioxide / Q000378:metabolism*; D009584:Nitrogen / Q000378:metabolism*; D010788:Photosynthesis / Q000502:physiology*; D014908:Triticum / Q000378:metabolism*
D002245:Carbon Dioxide; D009584:Nitrogen