Journal of Integrative Agriculture ›› 2014, Vol. 13 ›› Issue (11): 2416-2423.DOI: 10.1016/S2095-3119(13)60693-0

• 论文 • 上一篇    下一篇

Response of Nitrate Metabolism in Seedlings of Oilseed Rape (Brassica napus L.) to Low Oxygen Stress

 YU Chang-bing, XIE Yu-yun, HOU Jia-jia, FU You-qiang, SHEN Hong , LIAO Xing   

  1. 1、Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture/Oil Crops Research Institute, Chinese Academy of
    Agricultural Sciences, Wuhan 430062, P.R.China
    2、College of Resources and Environment, South China Agricultural University, Guangzhou 510642, P.R.China
  • 收稿日期:2013-10-12 出版日期:2014-11-06 发布日期:2014-11-14
  • 通讯作者: SHEN Hong, Tel: +86-20-85281822, E-mail: 40592487@qq.com; LIAO Xing, Tel: +86-27-86712256, E-mail: Liaox@oilcrops.cn
  • 作者简介:YU Chang-bing, Tel: +86-27-86712256, E-mail: cbyu123@163.com;
  • 基金资助:

    This research work is jointly supported by the Opening Foundation of Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture, P.R.China (201010), and the Cultivation Project of Guangdong Province Institute of Higher Education Talents at High Levels and the Public Welfare Industry Special Scientific Research Funds (201203032).

Response of Nitrate Metabolism in Seedlings of Oilseed Rape (Brassica napus L.) to Low Oxygen Stress

 YU Chang-bing, XIE Yu-yun, HOU Jia-jia, FU You-qiang, SHEN Hong , LIAO Xing   

  1. 1、Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture/Oil Crops Research Institute, Chinese Academy of
    Agricultural Sciences, Wuhan 430062, P.R.China
    2、College of Resources and Environment, South China Agricultural University, Guangzhou 510642, P.R.China
  • Received:2013-10-12 Online:2014-11-06 Published:2014-11-14
  • Contact: SHEN Hong, Tel: +86-20-85281822, E-mail: 40592487@qq.com; LIAO Xing, Tel: +86-27-86712256, E-mail: Liaox@oilcrops.cn
  • About author:YU Chang-bing, Tel: +86-27-86712256, E-mail: cbyu123@163.com;
  • Supported by:

    This research work is jointly supported by the Opening Foundation of Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture, P.R.China (201010), and the Cultivation Project of Guangdong Province Institute of Higher Education Talents at High Levels and the Public Welfare Industry Special Scientific Research Funds (201203032).

PDF

摘要： In order to understand the response of nitrate metabolism in seedlings of oilseed rape (Brassica napus L.) to low oxygen stress (LOS), two cultivars were studied at different light, LOS time and exogenous nitrate concentrations under hydroponic stress. Results show that N-uptake and dry matter of rape seedlings were decreased after LOS stress while nitrate accumulation (NA) under LOS was induced by darkness. Nitrate accumulation peaked at 3 d while root activity (RA, defined as dehydrogenase activity) decreased with prolonged waterlogging exposure. Exogenous nitrate significantly elevated NA and RA. Tungstate (TS) and LOS inhibited nitrate reductase (NR) activity while NR transcription and activity were enhanced by exogenous nitrate. Low oxygen stress stimulated the activity of superoxide dismutase (SOD) and peroxidase (POD) slightly, but inhibited that of catalase (CAT). B. napus L. Zhongshuang 10 (ZS10), a LOS tolerant cultivar, displayed smaller decrease upon dry matter under LOS, higher NA in darkness and lower NA in light than B. napus L. Ganlan CC (GAC), a LOS sensitive variety. ZS10 had lower NA and higher RA after waterlogging and exogenous nitrate treatment, and higher NR activity under TS inhibition than GAC, but the activity of antioxidant enzymes did not change under LOS. The results indicate that nitrate metabolism involved tolerance of rape seedlings to LOS, with lower accumulation and higher reduction of nitrate being related to higher LOS tolerance of rape seedlings exposed to waterlogging.

关键词: Brassica napus , low oxygen stress , nitrate accumulation , nitrate reductase , gene expression

Abstract: In order to understand the response of nitrate metabolism in seedlings of oilseed rape (Brassica napus L.) to low oxygen stress (LOS), two cultivars were studied at different light, LOS time and exogenous nitrate concentrations under hydroponic stress. Results show that N-uptake and dry matter of rape seedlings were decreased after LOS stress while nitrate accumulation (NA) under LOS was induced by darkness. Nitrate accumulation peaked at 3 d while root activity (RA, defined as dehydrogenase activity) decreased with prolonged waterlogging exposure. Exogenous nitrate significantly elevated NA and RA. Tungstate (TS) and LOS inhibited nitrate reductase (NR) activity while NR transcription and activity were enhanced by exogenous nitrate. Low oxygen stress stimulated the activity of superoxide dismutase (SOD) and peroxidase (POD) slightly, but inhibited that of catalase (CAT). B. napus L. Zhongshuang 10 (ZS10), a LOS tolerant cultivar, displayed smaller decrease upon dry matter under LOS, higher NA in darkness and lower NA in light than B. napus L. Ganlan CC (GAC), a LOS sensitive variety. ZS10 had lower NA and higher RA after waterlogging and exogenous nitrate treatment, and higher NR activity under TS inhibition than GAC, but the activity of antioxidant enzymes did not change under LOS. The results indicate that nitrate metabolism involved tolerance of rape seedlings to LOS, with lower accumulation and higher reduction of nitrate being related to higher LOS tolerance of rape seedlings exposed to waterlogging.

Key words: Brassica napus , low oxygen stress , nitrate accumulation , nitrate reductase , gene expression