摘要
通过水培试验,本文研究了施氮肥(尿素)对低镉处理下两种生态型东南景天根系形态及镉积累的影响。结果表明,在一定范围内供氮(4.0￣16.0mmol/L)能明显促进东南景天的根系生长,各项根系形态指标,如根系长度、根系表面积、根系直径、根体积和侧根均有升高,在16.0mmol/L达到最大值。但是,随着供氮(32.0￣64.0mmol/L)增加,表现出一定的负效应:东南景天的各项根系形态指标明显受到抑制,与对照相比差异达显著或者极显著水平。氮素对东南景天的镉积累有一定的促进作用,随着氮素用量的增加,体内镉积累逐渐升高,与根系形态不同的是,镉含量在氮水平32.0mmol/L条件下达到最大。研究结果表明适当提高营养液氮素水平有利于提高东南景天的各项根系形态指标以及对镉的吸收积累。
The effects of nitrogen on root morphology and cadmium accumulation in hyperaccumulator of Sedum alfredii Hance were investigated using hydroponic culture. The results indicated that root morphology parameter such as root length, root surface-area, root diameter and root volumn increased. when nitrogen level less than 16.0 mmol/L, and reached maximum at 16.0 mmol/L. When nitrogen level ≥32.0 mmol/L, the root morphology parameter of Sedum alfredii Hance was restrained markedly. cadmium accumulation in Sedum alfredii Hance was prompted by addition of urea and reached maximum at 32mmol/L which was differe from root morphology. All this results suggested that root morphology parameter and cadmium accumulation in Sedum alfredii Hance was prompted by increasing nitrogen level in growth solution.
出处
《中国农学通报》
CSCD
2007年第3期260-265,共6页
Chinese Agricultural Science Bulletin
基金
国家重点基础研究发展规划"973"项目"土壤-植物系统中重金属迁移
转化规律与农产品质量"(2002CB410804)
教育部长江学者和创新团队发展计划"污染环境修复与生态系统健康"(IRT0536)
上海市农委攻关项目"农田污染土壤的生物修复系统研究"(2004SA)
关键词
氮
根系形态
东南景天
镉
植物修复
Nitrogen, Root morphology, Sedum alfredii Hance, Cadmium, Phytoremediation
