【作者】 金勇； 郑进； 康薇； 胡红青； 刘永红； 朱俊； 付庆灵； 邹涛；

【Author】 Jing Yong~(1,2),Zheng Jin~2,Kang Wei~3,Hu Hongqing~1,Liu Yonghong~1,Zu Jun~1,Fu Qingling~1,Zou Tao~2 (1.College of Resource and Environment.Huazhong Agricultural University,Wuhan 430070,China; 2.Department of Chemical and Material Engineering,Huangshi Institute of Technology,Huangshi 435003,China; 3.Environment Science and Engineering College,Huangshi Institute of Technology,Huangshi 435003,China).

【机构】 华中农业大学资源与环境学院； 黄石理工学院化学与材料工程学院； 黄石理工环境科学与工程学院；

【摘要】 随着工农业和社会的发展,人们对环境的破坏也越来越严重,土壤重金属污染问题尤其受到人们的关注。重金属具有难降解、易积累、毒性大等特点,还可能进入食物链威胁到人类的健康,去除或固定土壤中重金属显得尤为重要。现今植物修复土壤重金属污染已成为了研究的热点。蓖麻是湖北省大冶市铜绿山Cu污染废弃地新发现的Cu超积累植物,相较于海州香薷、鸭跖草等Cu超积累植物,蓖麻拥有生物量大、经济价值高等优势。以往对超积累植物的研究,往往关注于整个植物对重金属的积累,或者对土壤的修复效果,而通过植物愈伤组织研究植物细胞耐Cu机理的报道较少。利用植物愈伤组织研究植物耐Cu机理,不仅可以大大缩短研究的周期,而且提供更易控制的实验环境,比完整的植株更能消除其他因素的影响。本文愈伤组织来自铜矿区野生蓖麻的种胚,选用MS为愈伤组织培养基,通过6-BA,NAA不同激素配比组合的试验。根据不同激素配比组合下愈伤组织的生长情况,确定最合适的培养配方为:6-BA0.8mg/L;NAA0.2mg/L;琼脂6g/L。以培养的蓖麻愈伤组织作为实验材料,沿用确定的最适培养基配方,将其转接到Cu浓度为20～80mg/L的培养基中,观察其生长情况。结果表明,随着Cu处理浓度的增加,蓖麻愈伤组织鲜重逐渐下降,即培养基中的Cu抑制了细胞的生长。与空白处理相比,含Cu 20mg/L的培养基中,愈伤组织长势良好,颜色鲜绿,但生物量较低;当培养基Cu浓度达到40mg/L时,颜色变深绿色;Cu浓度提高到60mg/L时蓖麻愈伤组织明显受到抑制,颜色变褐;在含Cu80mg/L的培养基中,蓖麻愈伤组织被严重抑制,生长极为缓慢,呈深褐色、发黑。在不同Cu浓度胁迫下,蓖麻细胞中的Cu含量随着Cu浓度的增加而增加,在处理Cu浓度60mg/kg时,细胞内Cu含量达到1466.10mg/kg,表现出很强的耐性。细胞内的Ca含量也随处理Cu浓度的增加而增加,Ca可使细胞内膜表面电势的电负性降低,可减少阳离子在膜表面活度,缓解Cu²⁺的毒性。细胞内Ca含量的增加是蓖麻细胞在Cu胁迫下的一种抗逆境反应,有利于保证细胞在高Cu浓度下的正常生长。该研究为土壤Cu污染治理和揭示蓖麻耐Cu机制提供了重要参考依据。更多还原

【Abstract】 Along with the development of agriculture and society,the destruction of the environment is more and more serious,heavy soil metal pollution problems especially caused people’s attention.Heavy soil metal is easy to accumulate,hard to degrade,it has high toxicity and other characteristics,may also enter into the food chain harm to human.So to remove or fix heavy metal in soil seems especially important.And recently plant repair of heavy soil metal pollution has been on focus. Ricinus communis is a new hyperaccumulator discovered in Tonglu Mountain,compared with Elsholtzia splendens,Commelina communis and other hyperaccumulator,Ricinus communis has more biomass,economic value.The study of hyperaccumulator used to focus on the accumulation of heavy metal over the whole plant,or the effect of soil renovation.My study,through the plant callus research on the mechanism of plant cells resistant on Cu,has fewer reports.The use of plants callus research on the resistance mechanisms of Cu,not only can greatly shorten the cycle of research,provide an easier controlled experimental environment,but also can eliminate the effects of other factors. The callus come from embryo of Ricinus communis in Daye copper mining,choose MS for callus culture medium,through the different hormone combination of 6-BA,NAA ratio test.According to different hormone ratio portfolio callus growth situation,choose the most appropriate training formula for: 6-BA 0.8 mg/L;NAA 0.2 mg/L;AGAR 6 g/L. Use the Ricinus communis callus as experimental material,continue to use the determined optimal formula of culture medium,transfer the Ricinus communis callus to medium with Cu concentration at 20～80 mg/L,observe the growth situation.The results show that,with the increase of the concentration of Cu, the callus’ fresh weight go down gradually,namely Cu in medium inhibits the growth of cells.Compared with the blank treatment,including Cu20mg/L medium,callus grow well,color is bright green,but the biomass is lower;When the culture medium Cu concentration goes to 40 mg/L,color becomes dark green; and when Cu concentration raised to 60 mg/L,obviously,callus are restrained,color becomes brown;In Cu80mg/L in medium,castor callus are seriously restrain,the growth is extremely slow,the color is puce. In different stress concentration,the content of Cu in callus increased by the increasing concentration. With the increase in the treatment of 60 mg/kg Cu concentration,the content in cells is 1466.10 mg/kg, showed a strong patience.Inside the cell Ca content increasing with the processing of Cu increase,Ca can make the cells lining the surface of the electric potential negative reduce electricity,reduce cation in membrane surface activity,alleviate Cu²⁺ toxicity.In Ricinus communis cells the increasing content of Ca in a reaction of adversity,ensure high concentration of Cu cells under the normal growth. The study provides an important reference for soil pollution control and reveals Ricinus communis of Cu resistance mechanism.更多还原