导　　师： 施国新

学科专业： G10

授予学位： 硕士

作　　者： ;

机构地区： 南京师范大学

摘　　要： 水体重金属污染已经成为一个日益严重的环境问题,了解水体重金属污染原理、处理水体重金属,已经成为一个必需解决的课题。由于重金属元素具有难降解、易积累、毒性大等特点,另外还能被水生植物富集吸收进入食物链危害人畜健康。因此,植物对重金属毒害的抗性机理以及提高植物抗重金属胁迫能力的探索研究越来越引起人们的关注。虽然铅/(Pb2+/)胁迫下植物的抗氧化反应已经有了一些报道,但有关于植物愈伤组织受到重金属胁迫后变化的研究报道较少。 目前,国内外对Pb2+毒害的研究对象多为自然生长的植物,主要研究了Pb2+对植物体生长发育过程的影响和植物生理过程的影响,也有少量文献涉及Pb2+对植物基因和氨基酸的影响。然而,利用水生植物愈伤组织进行重金属胁迫的研究还未见详细的报道。鉴于此,本文将分布广泛的挺水植物水花生进行愈伤组织培养,克服了光照、温度、水分及植物生长发育在自然状态下的不可控制性,使实验数据更具重复性和科学性。本文通过组织培养技术培养出水花生愈伤组织并以此为研究对象,以常见的污染环境的重金属离子——Pb2+为胁迫因子。将愈伤组织培养在人工模拟的含有这种典型重金属的培养液中,系统研究了水生植物愈伤组织抗重金属胁迫机理以及重金属离子在愈伤组织体内的富集变化、在细胞中的定位和对吸收矿质元素的影响。研究结果表明： /(1/)本文探讨了水花生愈伤组织的诱导,结果表明：水花生的茎段比叶片诱导愈伤率高,同时茎段所产生的愈伤组织质地紧密,体积较大且数量多,茎段仍为绿色,而叶片所产生的愈伤组织质地疏松,体积较小,且叶变枯黄；经过70/%酒精30s、5/%次氯酸钠10 min和0.1/%升汞10 min消毒后,愈伤组织的染菌率最低,控制在16.7/%内,且成活率可达63.3/%,灭菌效果最好；激� Heavy metal pollution of water bodies has become an increasingly serious environmental problem. Understand the principles of heavy metal contamination and heavy metals in water treatment have become a topic that must be addressed. Heavy metals can cause serious health hazards to animals and humans through the food chain due to the refractory, easy accumulation, toxicity and other characteristics. Therefore, much attention has been devoted to the studies on the mechanisms of heavy metal tolerance in plants and how to improve heavy metal tolerance of plants. Although antioxidative reactions of plants subjected to Pb2+ have been studied by several authors, there are less reports on the research of callus response to heavy metals. At present, the plants of natural growth were used as the object of Pb2+ poisoning study at home and abroad, mainly of the impact of Pb2+ on plant growth and development and plant physiological processes, but also a small amount of literature related to Pb2+ on the impact of plant genes and amino acids. However? the study of aquatic plant callus under heavy metals stress is also no detailed reports. In view of this, callus of Alternanthera philoxeroides was cultured to overcome the uncontrollability of light, temperature, moisture and plant growth and development in the natural state, so that the experimental data is more repeated and scientific. In this paper, callus of Alternanthera philoxeroides was cultured by tissue culture technique, which was used as experimental material, Pb2+ was selected as the stress factor. The callus was cultivated in solution containing different concentrations of Pb2+ under lab condition. The mechanisms for the protection of aquatic plant callus from the toxic effects of heavy metals as well as heavy metal accumulation in callus and the cellular localization and effect on the absorption of mineral elements were systemically studied. The results are as follow: /(1/) This paper discussed the induction of Alternanthera philoxeroides callus. The results s

关 键 词： 愈伤组织 水花生 抗氧化酶 亚细胞分布 矿质元素

领　　域： [生物学]