首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 359 毫秒
1.
以蚕豆根尖为材料,研究重铬酸钾对蚕豆根尖细胞的致畸效应。采用蚕豆根尖细胞的微核试验和染色体畸变试验方法,以不同浓度的重铬酸钾为诱变剂,测定蚕豆根尖细胞的微核率和染色体畸变率。结果表明:重铬酸钾能诱发较高频率的微核率,即在一定浓度范围内,其微核率随重铬酸钾处理浓度的升高而增加,但高于一定浓度后反而呈下降趋势;不同浓度的重铬酸钾均使蚕豆根尖细胞有丝分裂指数增大;重铬酸钾还能诱导蚕豆根尖细胞产生较高频率的染色体畸变,且产生多种类型的染色体畸变。结论是重铬酸钾对蚕豆根尖细胞具有明显的致畸效应。Abstract:We studied the aberrant effects of different concentrations of potassium dichromate on Vicia Faba root tip cells. The micronucleus and chromosome aberration assay was conducted to determine the micronucleus rate and chromosome aberration rate of Vicia faba root tip cells induced by potassium dichromate. The result indicated that potassium dichromate could increase the micronucleus rate of Vicia faba root tip cells. Within certain range of concentration the rate of micronucleus was found to be increased with the increase of potassium dichromate concentration,but beyond this range the rate of micronucleus decreased with further increase of potassium dichromate concentration. The potassium dichromate at different concentrations could increase the cell mitosis index. Besides,it also caused various types of chromosome aberration,and the rates of chromosome aberration were always higher than that of the control group. The conclusion of this study was that potassium dichromate has obvious teratogenic effect on vicia faba root tip cells.  相似文献   

2.
钱晓薇  朱小春  陈哲晓  林柳琴 《遗传》2002,24(3):305-309
本文以蚕豆根尖为材料,研究不同浓度As2O3在不同的处理时间内对蚕豆胚根根尖的细胞遗传学毒性效应。结果表明:不同浓度的As2O3在不同处理时间内均能诱发较高的微核率和染色体畸变率,并能有效地积累中期分裂相,阻止其进入后期与末期。结论是As2O3对蚕豆根尖细胞具有明显的细胞遗传学毒性效应,并具有积累有丝分裂中期细胞的效应。 Abstract:The cytogenetic toxic effects of different concentration of As2O3 within different time on the cell of Vicia Faba root tip were studied.The results indicate that the different concentrations of As2O3 can induce high frequency of micronucleus and chromosome aberration.Besides,it can accumulate the metaphases in mitosis efficiently and prevent the cells from continuing their cell cycle.It shows that As2O3 has marked cytogenetic toxic effect on the root tip cells of Vicia Faba,and effect of accumulating the metaphases in mitosis.  相似文献   

3.
用卡宝品红染色法检查格列那什二倍体葡萄(Vitis vinifera var. Cre nache)花药再生植株的染色体, 并用UNICHRO软件对其数目及长度进行了测量。结果表明,这些花药植株根尖中染色体组型为2n=3x=57的细胞平均占观察细胞总数的86.5%,来自不同花药的再生殖株均为三倍体。讨论了这些植株的可能来源。 Abstrart:The chromosome number in the root tip of triploid plants regenerated from anther culture of diploid Vitis vinifera var.Grenache were examined with Carbolfuchsin staining method and the length of chromosomes were measured with UNICHRO package.The results show that average pecentage of cells which have a karyotype for 2n=3x=57 in root tip of pollen plants were 86.5% in the total number of cells observed,the plants regenerated from different anthers are triploid.Their possible origin is discussed.  相似文献   

4.
NaCl胁迫对大麦细胞分裂及染色体行为的影响   总被引:5,自引:0,他引:5  
仪慧兰  张自立 《遗传》2001,23(1):29-32
NaCl溶液培养导致大麦幼苗根尖细胞有丝分裂指数下降,细胞姐妹染色单体交换(SCE)频率增高,且诱发包括染色体断片、后期染色体桥、不均等分裂及间期细胞微核等的染色体行为异常。细胞平均SCE频率及异常分裂细胞的比率与NaCl浓度和作用时间呈正相关。结果提示:NaCl浓度高或作用时间较长时对大麦细胞具有遗传学毒性。 Abstract:The effects of NaCl solution on chromosome behavior and sister chromatid exchanges(SCE)of barley were studied.Abnormal chromosome behavior including chromosome fragmentation,micronuclei,anaphase bridges and unequal split was found in root tip cells of Hordeum vulgare seedlings.Mitotic index decreased but SCE frequency increased significantly when barley incubated with NaCl solution.The effects of NaCl solution depended on its concentration and treatment duration.The higher the treated concentration was,the higher the ratio of chromosomal aberration was.The longer the treatment duration was,the higher the degree of the effects was.The results showed that NaCl solution was genotoxic when the concentration was higher and the treated time was longer.  相似文献   

5.
Cadmium (Cd) is one of the important pollutants of soil and the genotoxicity of Cd-contaminated soil was studied in combination with imidacloprid. The single cell gel electro-phoresis or comet assay was used to quantify DNA strand breaks as a measure of DNA damage induced by Cd and imidacloprid contamination in soil. The soil was artificially contaminated by Cd (0.0, 0.2, 0.5, 1.0, 2.0 mg·kg-1 dry soil) or Cd (0.0, 0.2, 0.5, 1.0, 2.0 mg·kg-1 dry soil) and imidacloprid (0.5 mg-kg~1 dry soil). Roots of Vicia faba were exposed to the contaminated soil for 2 h at 25℃and were used in the comet assay. DNA damage was measured as the values of percentage of nuclei with tails, tail length, tail DNA, tail moment (TM), and Olive tail moment (OTM). DNA damages of root tips of Vicia faba increased after Cd treatment and there were dose-related increases in DNA damage measured as these parameters. However, the addition of imidacloprid further increased the DNA damage. These data confirmed the genotoxic effect of Cd  相似文献   

6.
Rare earth elements have been emitted into the environment largely as fertilizer components. This has caused much fear about whether they would influence our environment, especially on the metabolism and genetics of microorganisms. In this article, the trivalent ion of a rare earth element, lanthanum, was studied for the effects on growth, transformation, and gene expression of Escherichia coli. The results showed that La3+ at concentrations from 50 to 150 μg/mL stimulated the endogenic metabolism and ectogenic metabolism, but had few effects on gene expression. La3+ at lower concentrations from 0.5 to 30 μg/mL inhibit intensively E. coli-absorbing external DNA, decreasing the transformation efficiency. It is also supported by observations using transmission electron microscopy. Our results are significant in understanding the function of rare earth elements to microorganisms and assessing the risk of application of rare earth compounds.  相似文献   

7.
In a previous study, a salt stress-induced programmed cell death (PCD) model was established in rice root tip cells. Here, by using Wuyunjing 8th rice seedlings, the effects of lanthanum on salt stress-induced PCD early events were studied. The results indicated that low concentrations (10 μmol/L), but not high concentrations (100 μmol/L) of LaCl3 could effectively prevent salt stress-induced PCD. Further study demonstrated that in the early stages of salt-induced PCD process, 10 μmol/L of La^3+ could prevent the increase of cytoplasmic calcium levels, inhibit reactive oxygen species (ROS) production, and enhance the ROS-scavenging enzyme activities such as superoxide dismutases (SOD) and ascorbate peroxidase (APX). Imidazole (20 mmol/L), the inhibitor of nicotinamide adenine dinucleotide phosphate-oxidase (NADPH oxidase), could alleviate the occurrence of PCD obviously, and such alleviation could be enhanced by the addition of La^3+, indicating the involvement of NADPH oxidase in the salt stress-induced PCD process. Taken together, lanthanum could prevent salt stress-induced PCD occurrence in the rice root tip cells by blocking the calcium influx under stress, which was followed by inhibiting calcium-dependent NADPH oxidase activity to prevent O2^·- production and, enhancing the cytosolic antioxidative enzyme activities to scavenge the reactive oxygen species.  相似文献   

8.
The regulation of stomatal movement is one of the most important signaling networks in plants.The H^ -ATPase at the plasma membrane of guard cells plays a critical role in the stomata opening, while there are some conflicting results regarding the effectiveness of the plasma membrane H^ -ATPase inhibitor,vanadate, in inhibiting stomata opening. We observed that 2 mmol/L vanadate hardly inhibited light-stimulated stomata opening in epidermal peels of Vicia faba L., but significantly inhibited dark- and ABA-induced stomatal closure. These results cannot be explained with the previous findings that H~-ATPase was inhibited by vanadate. In view of the fact that vanadate is an inhibitor of protein tyrosine phosphatases (PTPases),we investigated whether the stomatal movement regulated by vanadate is through the regulation of PTPase,As expected, phenylarsine oxide (PAO), a specific inhibitor of PTPase, has very similar effects and even more effective than vanadate. Typical PTPase activity was found in guard cells of V.faba; moreover, the phosphatase activity could be inhibited by both vanadate and PAO. These results not only provide a novel explanation for conflicting results about vanadate modulating stomatal movement, but also provide further evidence for the involvement of PTPases in modulating signal transduction of stomatal movement.  相似文献   

9.
Salt Stress-induced Programmed Cell Death in Rice Root Tip Cells   总被引:11,自引:0,他引:11  
Salt stressed rice root tips were used to investigate the changes of reactive oxygen species (ROS) and antioxidant enzymes at the early stages of programmed cell death (PCD). The results indicated that 500 mmol/L NaCI treatment could lead to specific features of PCD in root tips, such as DNA ladder, nuclear condense and deformation, and transferase mediated dUTP nick end labeling positive reaction, which were initiated at 4 h of treatment and pro- gressed thereafter. Cytochrome c release from mitochondria into cytoplasm was also observed, which occurred at 2 h and was earlier than the above nuclear events. In the very early phase of PCD, an immediate burst in hydrogen peroxide and superoxide anion production rate was accompanied by two-phase changes of superoxide dismutases and ascorbate peroxidase. A short period of increase in the activity was followed by prolonged impairment. Thus, we conclude that salt can induce PCD in rice root tip cells, and propose that in the early phase of rice root tip cell PCD, salt stress-induced oxidative burst increased the antioxidant enzyme activity, which, in turn, scavenged the ROS and abrogated PCD. Also, when the stress is prolonged, the antioxidant system is damaged and accumulated ROS induces the PCD process, which leads to cytochrome c release and nuclear change.  相似文献   

10.
Free cytosolic Ca^2+ ([Ca^2+]cyt) is an ubiquitous second messenger in plant cell signaling, and [Ca^2+]cyt elevation is associated with Ca^2+-permeable channels in the plasma membrane and endomembranes regulated by a wide range of stimuli. However, knowledge regarding Ca^2+ channels and their regulation remains limited in planta. A type of voltage- dependent Ca^2+-permeable channel was identified and characterized for the Vicia faba L. guard cell plasma membrane by using patch-clamp techniques. These channels are permeable to both Ba^2+ and Ca^2+, and their activities can be inhibited by micromolar Gd^3+. The unitary conductance and the reversal potential of the channels depend on the Ca^2+ or Ba^2+ gradients across the plasma membrane. The inward whole-cell Ca^2+ (Ba^2+) current, as well as the unitary current amplitude and NPo of the single Ca^2+ channel, increase along with the membrane hyperpolarization. Pharmacological experiments suggest that actin dynamics may serve as an upstream regulator of this type of calcium channel of the guard cell plasma membrane. Cytochalasin D, an actin polymerization blocker, activated the NPo of these channels at the single channel level and increased the current amplitude at the whole-cell level. But these channel activations and current increments could be restrained by pretreatment with an F-actin stabilizer, phalloidin. The potential physiological significance of this regulatory mechanism is also discussed.  相似文献   

11.
重铬酸钾对蚕豆根尖细胞致畸效应的研究   总被引:27,自引:0,他引:27  
钱晓薇 《遗传》2004,26(3):337-342
以蚕豆根尖为材料,研究重铬酸钾对蚕豆根尖细胞的致畸效应。采用蚕豆根尖细胞的微核试验和染色体畸变试验方法,以不同浓度的重铬酸钾为诱变剂,测定蚕豆根尖细胞的微核率和染色体畸变率。结果表明:重铬酸钾能诱发较高频率的微核率,即在一定浓度范围内,其微核率随重铬酸钾处理浓度的升高而增加,但高于一定浓度后反而呈下降趋势;不同浓度的重铬酸钾均使蚕豆根尖细胞有丝分裂指数增大;重铬酸钾还能诱导蚕豆根尖细胞产生较高频率的染色体畸变,且产生多种类型的染色体畸变。结论是重铬酸钾对蚕豆根尖细胞具有明显的致畸效应。  相似文献   

12.
本实验研究了甲硝唑诱导蚕豆根尖细胞微核的效应。实验表明:(1)浓度为0.1、6、12、40和500 mg/L甲硝唑均能使蚕豆根尖细胞微核率显著增加,且蚕豆根尖细胞微核率和甲硝唑浓度之间存在明显的剂量—效应关系;(2)甲硝唑能引起DNA损伤,具有分子诱变剂的性能。  相似文献   

13.
利用蚕豆根尖微核技术监测化工铬渣堆场渗出液的遗传毒性,结果表明,化工铬渣渗出液含有较高浓度的Cr6+,能明显诱导蚕豆根尖细胞微核的形成,具有较强的遗传毒性。当铬渣渗出液中Cr6+浓度为186.6460 mg/L时,微核率达到最大。铬渣渗出液所诱导的微核率与阴性对照组相比有极显著差异。  相似文献   

14.
乙酸铜对蚕豆根尖细胞致畸效应   总被引:11,自引:0,他引:11  
采用蚕豆根尖细胞的微核试验和染色体畸变试验方法,以不同浓度的乙酸铜为诱变剂,选择不同的处理时间,测定蚕豆根尖细胞的有丝分裂指数、微核率和染色体畸变率。结果表明:乙酸铜能诱发较高频率的微核率,处理6h、12h时微核率均随着乙酸铜浓度的升高而增加,具有明显的剂量效应;处理24h时在实验浓度范围内,其微核率随乙酸铜浓度的升高而增加,但高于一定浓度后反而呈下降趋势。不同浓度的乙酸铜在不同处理时间均使蚕豆根尖细胞有丝分裂指数增大。乙酸铜还能诱导蚕豆根尖细胞产生较高频率的染色体畸变,且产生多种类型的染色体畸变。因此,乙酸铜对蚕豆根尖细胞具有明显的致畸效应。  相似文献   

15.
硫酸铜对蚕豆根尖细胞有丝分裂的影响   总被引:14,自引:0,他引:14  
以蚕豆根尖为材料,研究硫酸铜对蚕豆根尖细胞的遗传毒性效应。采用蚕豆根尖细胞的微核试验方法和染色体畸变试验方法,以不同浓度的硫酸铜为诱变剂,测定蚕豆根尖细胞的有丝分裂指数、微核率和染色体畸变率。结果表明:不同浓度的硫酸铜均能使蚕豆根尖细胞有丝分裂指数明显增加,即5个实验组的分裂指数均明显高于对照组(P<0.01或P<0.001);不同浓度的硫酸铜对蚕豆根尖细胞有丝分裂各期百分数的影响有异;能诱发较高频率的微核率,即在一定浓度范围内,其微核率随硫酸铜处理浓度的升高而增加,但随着硫酸铜浓度的进一步升高而呈下降趋势;硫酸铜还能诱导染色体产生多种类型的畸变,染色体畸变率随硫酸铜处理浓度的升高而增加,随着硫酸铜浓度的进一步升高而呈下降趋势,但均明显高于对照组(P<0.001)。结论是硫酸铜对蚕豆根尖细胞具有明显的遗传毒性效应。  相似文献   

16.
浊漳河水体污染物对蚕豆根尖细胞的遗传毒性研究   总被引:2,自引:0,他引:2  
运用蚕豆根尖细胞微核试验技术对浊漳河南段6个代表性样点水体中有机污染物的遗传毒性进行了研究,为浊漳河流域水体污染状况的有效监测提供理论依据.结果显示:(1)浊漳河南段各监测断面的水体有机污染物对蚕豆根尖细胞均产生了不同程度的损伤,表现出细胞微核、断片、染色体桥等多种异常形态,严重时导致细胞坏死和细胞凋亡.(2)6个样点水样处理的蚕豆根尖细胞微核率在21.47‰~64.77‰,极显著高于对照组(P<0.01).(3)各样点水样对蚕豆根尖细胞的遗传损伤程度依次为:王桥>店上>漳泽水库>北寨>黄碾>五阳;在有丝分裂后期,蚕豆根尖中异常细胞最高达70%,且异常细胞比率有随着污染程度增大而升高的趋势.研究表明,蚕豆根尖细胞微核是水质毒理检测的有效指标,其细胞有丝分裂后期异常细胞比率也可作为水质毒理检测的观察指标.  相似文献   

17.
以蚕豆种子为材料,采用水培方法研究废电池浸出液对蚕豆种子萌发及根尖细胞有丝分裂的影响。结果表明,不同浓度废电池浸出液对蚕豆根、芽的萌发及根尖细胞有丝分裂都产生一定程度的抑制作用,并随着浓度的增加,抑制作用逐渐增大,同时微核率也快速上升。本试验表明,较高浓度的废电池浸出液是毒性很强的溶液,属重度污染液。  相似文献   

18.
应用微核技术对北京三海水域污染状况的研究   总被引:16,自引:0,他引:16  
2003和2004年于北京三海(西海、后海和前海)分别采集21、22个样品,利用蚕豆根尖微核技术对水体的污染状况进行了遗传毒性分析。结果表明,水体总体显示出不同程度的遗传毒性特征。2003、2004两年中,微核相对率〈1.5的样本分别占4.7619%、18.1818%,主要分布于前海和后海湖心区域;微核相对率为1.5~2.0的样本分别占28.5714%和13.6364%;微核相对率为2.0~3.5的样本分别占28.5714%和45.4545%;微核相对率〉3.5的样本分别占38.0952%和22.7273%。其中。在民居密集的西海区域,两年重度污染率均达到40%。结果表明,水体污染程度与人为因素具有显著相关。本文对试验方法亦进行了讨论。  相似文献   

19.
朱大明  廖义军 《生态科学》2007,26(2):151-154
为了研究2006年9月广州郊区某鱼塘因化工企业污染源废水进入而导致大量死鱼事件中鱼类死亡原因,用斑马鱼(Brachydanio rerio)和蚕豆(Vicia faba)根尖对污染源废水及鱼塘水分别进行了鱼类急性毒性试验和蚕豆根尖微核试验.污染源废水和鱼塘水的96hLC50分别为1.69%、23.95%,污染源废水和鱼塘水的微核率分别为27.8‰、13.7‰,污染源废水和鱼塘水的COD、BOD、石油类、氨氮、总磷等均出现超标情况,其中氨氮、苯胺、石油类污染物严重超标.监测结果表明,以氨氮污染为主的污染源废水是导致死鱼事件的主要原因,废水对蚕豆根尖微核率的形成具有显著性影响,可能存在潜在的致突变性危险.  相似文献   

20.
万宁佳  李可念  陈劲松  刘洪宇 《广西植物》2018,38(12):1641-1650
外来入侵植物可以通过淋溶、自然挥发、根系分泌和植株凋落物分解等途径向周围环境释放化感物质,抑制伴生植物的生长、发育。该研究以不同浓度紫茎泽兰(Eupatorium adenophorum)叶片水浸液处理蚕豆(Vicia faba)种子,研究紫茎泽兰叶片水浸液对蚕豆根尖细胞微核、染色体畸变、细胞凋亡、蚕豆幼苗叶片叶绿素和N含量、光合生理特性、生物量的影响。结果表明:(1)紫茎泽兰叶片水浸液处理显著抑制蚕豆根尖的伸长和细胞的有丝分裂,并诱导蚕豆根尖细胞染色体畸变和细胞微核的产生,有丝分裂指数随着叶片水浸液浓度增加而减小,根尖细胞微核率随叶片水浸液浓度增加而增大,高浓度叶片水浸液处理对蚕豆根尖细胞的凋亡及坏死有明显影响。(2)紫茎泽兰叶片水浸液处理引起蚕豆幼苗叶片的叶绿素和N含量显著降低,并导致蚕豆幼苗最大净光合速率和生物量的显著下降。总之,紫茎泽兰叶片水浸液可能引起蚕豆根尖的氧化损伤和抑制根尖的伸长,且叶片水浸液的抑制作用呈现一定的剂量效应。紫茎泽兰叶片水浸液对蚕豆根尖的损伤和抑制作用可能影响了植株对氮素的吸收,进而对蚕豆幼苗光合生理表现以及生物量积累产生显著负面效应。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号