长春花是我国广泛栽培兼具园林绿化和抗癌药源等重要价值的多年生草本花卉植物.为了解镉胁迫下长春花的生长适应性和对养分的吸收和利用,采用盆栽试验研究了不同镉处理(0,5,10,25,50,100 mg/kg)下长春花生长、生物量及养分(C、N、P和K)积累与分配特征.结果表明,随镉处理浓度的增加,植物各器官镉积累量升高；除叶片P积累量降低外,植物各器官生物量生产及C、N、P和K积累量均表现出先升高后降低的趋势.较高浓度镉处理(≥25 mg/kg)明显抑制了长春花的生长特性、生物量生产以及C、N、P和K的积累,显著改变了生物量及其C、N、P和K积累量的分配格局,但相对低浓度的镉处理(≤10 mg/kg)并无显著影响.一定程度上,长春花对镉具有较强的耐性,为城市园林绿化和净化重金属污染土壤提供了可能,在镉污染土壤的修复中具有一定的应用潜力.%Little information has been available on the effects of soil cadmium contamination on plant nutrition.Because of the economical and biological benefits,ornamental plant has become a new source for phytoremediation in recent years.The valuable ornamental plant Catharanthus roseus is an important landscaping and anticancer drug source plant which is widely distributed in city gardens and on roadsides in China.In order to understand the effects of different cadmium stress on the growth and nutrient characteristics in C.roseus.A controlled pot-experiment was arranged with different treatments of six cadmium concentrations (0,5,10,25,50 and 100 mg/kg) to investigate the growth characteristics,biomass production and accumulation and distribution of carbon(C),nitrogen(N),phosphorus(P)and potassium(K)in C.roseus.The results indicated that the roots,stems and leaves cadmium accumulation increased with increased Cd supplies,while the plant organs biomass production and C,N,P and K accumulation showed the trend of increased at first,and then decreased except leaf P accumulation decreased.The treatments with higher cadmium concentrations(≥25 mg/kg)significantly inhibited C.roseus growth,biomass and C,N,P and K accumulation,as well as altered their distribution patterns,while the treatment with lower cadmium concentration(≤10 mg/kg)had no significant effects.To a certain extent,C.roseus has stronger tolerance to cadmium contamination.These results implied that C.roseus is a possible for urban landscaping and purification of heavy metal contaminated soil,and has some potential applications in the remediation of cadmium polluted soil.
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