欢迎访问《生态学杂志》官方网站,今天是 分享到:

生态学杂志 ›› 2012, Vol. 31 ›› Issue (06): 1327-1333.

• 研究报告 • 上一篇    下一篇

拟南芥铵超敏感突变体amosdvtc1对外源铵的影响

董刚强1,2,冯晓宇1,2,李光杰1,2,李保海1,李青1,施卫明1**   

  1. (1土壤与农业可持续发展国家重点实验室, 中国科学院南京土壤研究所, 南京 210008; 2中国科学院研究生院, 北京 100049)
  • 出版日期:2012-06-09 发布日期:2012-06-09

Responses of Arabidopsis thaliana's ammonium-hypersensitive mutants amosdand vtc1 to exogenous ammonium.

DONG Gang-qiang1,2, FENG Xiao-yu1,2, LI Guang-jie1,2, LI Bao-hai1, LI Qing1, SHI Wei-ming1**   

  1. (1State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China;  2Graduate University of Chinese Academy of Sciences, Beijing 100049, China)
  • Online:2012-06-09 Published:2012-06-09

摘要: 分析了不同外源铵浓度(0、1、5、10、20 mmol·L-1)处理下,2个铵超敏感突变体amosdvtc1对于外源铵处理的响应差异。结果表明,尽管amosdvtc1都表现为对外源铵超敏感,但二者对外源铵处理浓度的敏感性上存在差异。随着外源铵浓度的增加,vtc1比amosd先表现出铵中毒症状,更高浓度(20 mmol·L-1)铵处理时amosd受到的毒害程度表现更加严重,AMOSD遗传位点的缺失容易导致植物出现铵毒害死亡。其次,二者在遭受外源铵胁迫时表现的最敏感部位有所不同,主要的毒害特征上存在差异,amosd在铵胁迫下首先表现在叶片尤其是新叶的发育受阻,而vtc1则主要表现在根部尤其是主根的伸长受阻。通过分区供应实验证明,amosd主要对于地上部供铵处理超敏感,对根部供铵处理不表现超敏感特性;而vtc1则相反,对根部供铵处理超敏感,对地上部供铵不表现超敏感特性。由此可见,amosdvtc1这2个铵超敏感突变体在拟南芥铵毒害范围和部位上存在较大差异,与vtc1有所不同,amosd是一个叶源铵超敏感型突变体。在农业机械化叶面喷施施肥日益增加和环境铵沉降日益严重的当下,叶源型铵超敏感突变体amosd的获得为揭示植物地上部铵毒害机制提供了一个理想的遗传材料,对系统全面认识植物铵毒害机制,提高作物耐铵性状具有十分重要的意义。

关键词: 产量, 气候变化, 胡麻, 发育进程

Abstract: This paper analyzed the differences in the responses of Arabidopsis thaliana’s two ammoniumhypersensitive mutants, amosd and vtc1, to exogenous ammonium at concentrations 0, 1, 5, 10, and 20 mmol·L-1. The two mutants all showed ammonium-hypersensitive, but the sensitivity degree differed. With the increasing concentration of exogenous ammonium, the vtc1 showed ammonium toxicity earlier than amosd. However, when the exogenous ammonium concentration increased up to 20 mmol·L-1, the amosd showed heavier toxicity symptom than vtc1, suggesting the vital roles of AMOSD in plant tolerance to high ammonium stress. When the two mutants suffered from the stress of exogenous ammonium, the plant tissues where the highest toxicity degree occurred had somewhat difference. As the amosd suffered from the stress, the development of true leaves was arrested most; when the vtc1suffered from the stress, root elongation was repressed most. Partial ammonium supply experiment showed that the amosd had ammonium- hypersensitivity when the shoots were supplied with ammonium, while the vtc1 did not have the same phenotype unless the roots were supplied with ammonium. These results clearly indicated that vtc1 was a root-supply ammonium hypersensitive mutant, while amosd was a leaf-supply ammonium hypersensitive one. With the development of foliar spraying and the increasing deposition of ammonium from atmosphere, plants are facing higher and higher ammonium stress, and thus, it is of importance to increase the plant shoot tolerance to ammonium stress. This study indicated that, due to its unique characteristics of hypersensitive to shoot-supply ammonium, mutant -amosd could be a suitable genetic material to study the mechanisms of plant shoot tolerance to ammonium stress, and useful to more systemically understand the mechanisms of plant ammonium toxicity and improve plant ammonium tolerance.

Key words: climate change, flax, development, yield.