摘要：
The relationship between nitrogen efficiency (NE), defined as seed yield per unit nitrogen (N) application, and seed quality was examined in two oilseed rape (Brassica napus L.) varieties at 5 N application levels, 0.6, 3, 6, 12, 15 mmol L-1, N1, N2, N3, N4 and N5, respectively. Seed yield, oil yield and protein content were increased with the increase in N application level, but NE and oil content were decreased, and the fatty acid composition in seed was hardly changed. Analysis of seven fatty acids revealed a slight decrease in the contents of erucic acid and arachidonic acid with the increase in N application level, but no obvious change in the contents of palmitic acid, stearic acid, oleic acid, linoleic acid and linolenic acid. Compared with the low NE variety H29, the seed yield and contents of erucic acid and arachidonic acid in the high NE variety bin270 were more markedly increased with the increase in N application level, and the oil content was hardly changed. The seed yield, oil content and oil yield were higher in the high NE variety than in the low NE variety at all 5 N application levels. There were no significant differences in protein, palmitic acid, stearic acid and oleic acid contents between the varieties at any of the 5 N application levels, but there were slight differences in the linoleic acid and linolenic acid contents between the two varieties. In brief, N application improved oil yield more greatly in the high NE variety than in the low NE variety, but hardly affected the fatty acid composition. Therefore, the seed quality and oil content of oilseed rape may not be decreased by breeding of a high NE variety with a high N absorption efficiency and high N use efficiency.
作者机构：
[黄海涛] College of Resource and Environment, Hunan Agricultural University, Changsha 410128, China;National Engineering Laboratory of High Utilization Efficiency of Soil Fertilizer Resource, Changsha 410128, China;[官春云] National Center of Oilseed Crops Improvement, Hunan Branch, Changsha 410128, China;[彭建伟; 张振华; 荣湘民; 刘强; 宋海星] College of Resource and Environment, Hunan Agricultural University, Changsha 410128, China, National Engineering Laboratory of High Utilization Efficiency of Soil Fertilizer Resource, Changsha 410128, China
通讯机构：
[Huang, H.-T.] C;College of Resource and Environment, Hunan Agricultural University, China
摘要：
Combined application of synthetic nitrogen (N) fertilizers and organic materials can enhance soil quality, but little is known about the distribution of fertilizer N among different soil fractions after crop harvest. A pot experiment using 15N tracer was employed to address this question with three treatments, i.e., labeled urea-only (15NU), labeled urea + rice straw (15NU-S) and labeled rice straw + urea (15NS-U) applied to a Ferallic Cambisol (1:1 type soil clay mineral) and a Calcaric Fluvisol (2:1 clay mineral). Soil microbial biomass N, fixed ammonium (fixed NH
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), exchangeable ammonium and soil organic N fractions by hydrolysis (6 N HCl) and their isotope abundance were determined after the rice harvest. Soil newly formed N in urea + straw (U-S) treatments (15NU-S, 15NS-U) was the sum of labeled urea-N in 15NU-S and labeled straw-N in 15NS-U. Compared with 15NU, U-S significantly (P < 0.05) increased the content and percentage of newly formed total soil N, acid insoluble N, amino acid N, and hydrolysable unknown N in both soils. In U-S treatment, straw amendment significantly (P < 0.05) reduced the content and percentage of newly formed fixed-NH
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-N in Fluvisol as compared with 15NU treatments. Soil microbes contributed to the larger percentage of newly formed amino acid N (P < 0.01) in Cambisol as compared with Fluvisol. Fertilizer N in various soil fractions was therefore strongly affected by clay mineral type and microbes after the combined application of organic materials and synthetic N fertilizer.
作者机构：
[Zheng Xiaodong; Zhang Zhenhua; Rong Xiangmin; Luo Zunchang; Liu Qiang; Song Haixing; Peng Jianwei; Xie Guixian; Zhang Yuping; Gu Jidong] College of Resources and Environment,Hunan Agricultural University;[Zheng Xiaodong; Zhang Zhenhua; Rong Xiangmin; Luo Zunchang; Liu Qiang; Song Haixing; Peng Jianwei; Xie Guixian; Zhang Yuping; Gu Jidong] Soil and Fertilizer Institute of Hunan Province;[Zheng Xiaodong; Zhang Zhenhua; Rong Xiangmin; Luo Zunchang; Liu Qiang; Song Haixing; Peng Jianwei; Xie Guixian; Zhang Yuping; Gu Jidong] Hunan Provincial Key Lab. Plant Nutrition Common University;[Zheng Xiaodong; Zhang Zhenhua; Rong Xiangmin; Luo Zunchang; Liu Qiang; Song Haixing; Peng Jianwei; Xie Guixian; Zhang Yuping; Gu Jidong] Hunan Provincial Key Lab. Farmland Pollution Control Agri. Resources Use;[Zheng Xiaodong; Zhang Zhenhua; Rong Xiangmin; Luo Zunchang; Liu Qiang; Song Haixing; Peng Jianwei; Xie Guixian; Zhang Yuping; Gu Jidong] School of Biological Sciences,The University of Hong Kong
会议名称：
Environmental Pollution and Public Health(EPPH 2012)
会议时间：
2012-05-17
会议地点：
中国上海
摘要：
In order to study the research development of different remediation methods and the future works of heavy metal pollution, we will give a brief summary of current situation of soil heavy metal polluti
