Population Dynamics of Rhizosphere Diazotroph Assemblages - Effects of Host and Environmental Variables

根际固氮微生物组合的种群动态 - 寄主和环境变量的影响

• 批准号: 9903623
• 负责人: Charles Lovell
• 金额: $ 24.4万
• 依托单位: University of South Carolina at Columbia
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-08-01 至 2002-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9903623&HistoricalAwards=false
• 关键词: Population; Dynamics; Rhizosphere; Diazotroph; Assemblages

Lovell9903623The supply and regeneration of nutrients in ecosystems are usually strongly influenced by microbial communities. These processes can be particularly affected by environmental stress. The salinity conditions in salt marsh ecosystems generate frequent occurrences of environmental stress and the dominant plant species in eastern US marshes, Spartina alterniflora, exhibits distinct patterns of growth forms that are correlated with changing salt conditions. This proposal will test the notion that the changes in plant growth form in salt marshes are mediated by salinity induced shifts in bacterial N fixation, a critical microbial process in the root zone. The project will employ molecular biological techniques to examine the response of root-zone, N-fixing bacteria to key environmental stresses. It will examine the generality of its findings by evaluating sites near the northern and southern limits of east coast S. alterniflora occurrence. It will provide general insights into the responses of N-fixing bacterial assemblages to environmental stress.

生态系统中营养物质的供应和再生通常受到微生物群落的强烈影响。 这些过程尤其会受到环境压力的影响。 在盐沼生态系统的盐度条件下产生频繁发生的环境压力和美国东部沼泽，互花米草，优势植物物种，表现出不同的生长形式，与不断变化的盐条件。 这个建议将测试的概念，在盐沼植物生长形式的变化介导的盐诱导细菌固氮，在根区的一个关键的微生物过程中的转变。 该项目将采用分子生物学技术来研究根区固氮细菌对关键环境压力的反应。 它将通过评估东海岸S的北方和南方界限附近的地点来检查其调查结果的一般性。互花米草发生 它将提供一般的见解固氮细菌组合体对环境压力的反应。