Cd胁迫对5种植物体内Cd积累及根际土壤特性的影响  

Effects of Cd Stress on Cd Accumulation in Organs and Rhizospheric Soil Characteristics with Five Plants

作　　者：杨珍平[1] 郝教敏[2] 卜玉山[3] 高志强[4] 苗果园[1] 

机构地区：[1]山西农业大学农学院,山西太谷030801 [2]山西农业大学食品学院,山西太谷030801 [3]山西农业大学资源环境学院,山西太谷030801 [4]山西农业大学研究生院,山西太谷030801

出　　处：《水土保持学报》2011年第6期186-192,共7页Journal of Soil and Water Conservation

基　　金：现代农业产业技术体系建设专项基金(CARS-03);国家自然科学基金项目(31101113);山西省自然基金项目(991102);山西省青年基金项目(20031047)

摘　　要：以大豆、棉花、曼陀罗、蓖麻和玉米为供试材料,采用土柱栽培试验,探讨Cd胁迫后,5种植物根系活力与各器官间Cd含量的差异,以及5种植物根际土壤酶活性与根际土壤营养含量对Cd胁迫的反应。结果表明:(1)5种受污染的植物体Cd富集量超出对照不受污染的植物体达3～7倍之多,但都未达富集临界值100mg/kg。(2)不同植物不同器官Cd运转积累部位不同,以根冠比衡量,蓖麻、玉米、棉花R/S大于1,称作根优势植物;大豆、曼陀罗R/S小于1,称作冠优势植物;棉花R/S近于1,称作冠根均衡植物。5种植物吸收富集最强的前3位植物(大豆、玉米、棉花)都是人工驯化的栽培植物,其吸肥能力强于野生植物的,这种吸肥能力与吸Cd能力是否呈正相关关系,吸肥能力的差异是否可以作为污染土壤利用改良的依据值得进一步研究。(3)大豆、曼陀罗茎秆中Cd含量均较根、叶、籽实中的高,考虑到大豆是粮食作物,同时其根部Cd含量仅次于茎的,而曼陀罗作为一种杂草,其地上部Cd转移系数大于1.0,因此,比较供试5种植物,应优先选择曼陀罗用于Cd污染区域的土壤净化。(4)Cd胁迫(5mg/kg)提高了5种植物根系还原TTC强度,抑制了大豆和蓖麻根际土壤多种酶活性,而促进了曼陀罗和玉米根际土壤多种酶活性以及棉花根际土壤脲酶、蔗糖酶和碱性磷酸酶活性;比较5种酶活性,碱性磷酸酶活性对Cd反应较不敏感,脲酶和蔗糖酶活性对Cd反应较敏感,多酚氧化酶和过氧化氢酶活性对Cd的敏感程度因不同植物而异。结果还表明Cd胁迫不同程度地提高了供试5种植物根际土壤营养含量。(5)研究为有效开展Cd污染土壤的植物修复资源提供理论依据。Phytoremediahon is a promising new method that is used green planted to take up or deloxify Cd from contaminated soils. With soybean （ Gl ycine max）, cotton （ Goss ypium hirsutum ） , dutura （ Dature stra- monium Datura）, castor oil plant （Ricinus comrnunis） and maize（Zea rnays） as materials, soil column culture experiment was used to study differences of root activities, Cd accumulation in organs, rizhospheritic soil en- zymes activities and soil nutrition contents of five plants under Cd（5 mg/kg） stress. The results indicated. （1） Under Cd（5 mg/kg） stress enrichment contents of Cd for five plants were more from three to seven multi- ples than that of CK, but all of them could not attained critical concentration with 100 mg/kg what Cd hyper- accumulator should accumulate. （2）For different plants, the ratios of Cd accumulation in organs were differ- ent, if the ratio of root and shoot（R/S）was regarded as judgment index, castor oil plant and maize were called as root superiority plants because their R/S were greater than 1, soybean and dutura were called as shoot superiority plants because their plants because its R/S was close to 1. R/S were less than 1, and cotton The enrichment contents of Cd for was called as shoot-root balanced soybean, maize and cotton ranked with the first the second and the third respectively, since abilities of absorbing fertilizer were greater than those of absorbing fertilizer with absorbing Cd positive？ Could the the three plants were cultivated by aritificial, their uncultivated plants, then, was the correlation of difference of absorbing fertilizer abilities be regar- ded as an index for utilizing and improving pollution soil？ These problems were worth studying furthermore. （3）Soybean and dutura Cd contents of shoot were more than those of root, leaf or seed, considering that soy- bean was not only a kind of food crop but also Cd content of its root ranked only second to shoot, but dutura was not only a kind of weeds but also its Cd tran

关 键 词：镉胁迫 镉积累 根系活力 根际土壤酶 根际土壤营养 

分 类 号：X171[环境科学与工程—环境科学] S154.2[农业科学—土壤学]