离子液体氯化1-辛基-3-甲基咪唑对洋葱的遗传毒性作用

为探讨咪唑类离子液体氯化1-辛基-3-甲基咪唑([C_8mim][C1])对洋葱的遗传毒性,用浓度分别为2.5、5、10和20mmol·L~(-1)的[C_8mim][C1]处理洋葱内表皮细胞和洋葱根尖8 h,用浓度为10 mmol·L~(-1)的[C_8mim][C1]处理洋葱内表皮细胞和洋葱根尖4 h、8 h、12 h和24 h,研究[C_8mim][C1]对洋葱内表皮细胞核的影响和对洋葱根尖有丝分裂指数和染色体畸变的影响。结果显示,与对照组相比,随着[C_8mim][Cl]处理浓度和时间的增加,洋葱内表皮细胞核偏移率明显升高,根尖细胞有丝分裂指数显著降低,染色体畸变现象明显,畸变率升高。研究表明,当浓度达到2.5 mmol·L~(-1)时,[C_8mim][Cl]对洋葱具有遗传毒性。     

农药氰戊菊酯和三氟氯氰菊酯对蚕豆根尖细胞的遗传损伤

采用蚕豆根尖微核技术研究了农药氰戊菊酯、三氟氯氰菊酯对蚕豆根尖细胞的遗传损伤.测定了不同浓度氰戊菊酯、三氟氯氰菊酯(5×10-10～5×10-2g·L-1)诱导下的蚕豆根尖细胞微核率、有丝分裂指数和染色体畸变率.结果表明,氰戊菊酯、三氟氯氰菊酯均能诱发较高的微核率,在一定浓度范围内,微核率随两种农药处理浓度的升高而增加,但随着处理浓度的进一步升高微核率反而呈下降趋势;两种农药均可使蚕豆根尖细胞有丝分裂指数增大;并能诱导蚕豆根尖细胞产生较高频率、多种类型的染色体畸变.氰戊菊酯和三氟氯氰菊酯对蚕豆根尖细胞具有明显的遗传毒性.     

镉对小麦根尖细胞的遗传损伤效应

为了研究重金属镉对小麦是否产生细胞毒性和遗传毒性效应,采用不同浓度镉对小麦根尖处理24、48、72 h,统计有丝分裂指数、微核率及染色体畸变率.结果表明,1 μmol·L-1镉可提高小麦根尖细胞有丝分裂指数,但随镉处理浓度的提高和处理时间的延长,有丝分裂指数逐步下降;4个时期相比,镉对有丝分裂前期和中期的影响较小.微核率随着镉处理浓度的提高而增加,但浓度过高时,微核率随着镉处理时间的延长反而有所降低.此外,染色体畸变率也逐步上升,且随镉浓度的增加和处理时间的延长,其作用效果急剧加大,呈现明显的剂量-效应、时间-效应关系.说明镉可引起小麦根尖细胞有丝分裂抑制和染色体损伤,具有明显的遗传毒性.     

蚕豆根尖微核试验在辣子草化感作用研究中的应用

运用蚕豆(Vicia faba L.)根尖细胞微核试验,研究入侵植物辣子草(Galinsoga parviflora Cav.)水浸提液的化感效应,结果表明,辣子草水浸提液具有一定的遗传毒性.在辣子草水浸提液作用下,蚕豆根尖细胞有丝分裂各时相受到影响,有丝分裂指数下降,微核率升高,细胞中出现了微核、染色体断片、染色体桥、染色体滞留等多种染色体畸变,辣子草水浸提液对蚕豆根尖的影响存在显著的时间效应和浓度效应.蚕豆根尖微核技术能较好的反映辣子草化感作用潜力,在评估入侵植物的化感作用方面具有较大的应用价值.     

模拟酸雨及Al3+共同作用对蚕豆根尖细胞的遗传损伤

以蚕豆为材料,研究了模拟酸雨及酸雨与铝共同作用的细胞遗传学效应.结果表明,根尖细胞有丝分裂指数随Al3 浓度的升高和环境酸度的增强而下降;处理组细胞中出现了多种染色体异常,如染色体粘连、滞后及断裂等.模拟酸雨及其与低浓度Al3 (3mg/L)共同作用时可诱发蚕豆根尖细胞微核,其中pH4.5组微核率高于pH3.5组.模拟酸雨与高浓度的Al3 (10～180mg/L)复合处理可引起根尖细胞固缩,固缩率随Al3 浓度增加和pH降低而增高.研究结果表明,pH4.5和pH3.5的模拟酸雨和Al3 对蚕豆根尖细胞具有遗传损伤作用,其效应与Al3 浓度和环境酸度有关.     

农药乙蒜素和细菌溴腈对蚕豆根尖细胞的致畸效应

利用蚕豆根尖微核技术研究农药乙蒜素和细菌溴腈对蚕豆根尖细胞的遗传损伤,测定蚕豆根尖细胞的微核率、有丝分裂指数和染色体畸变率.结果表明:2种农药均能诱发较高频率的微核率、有丝分裂指数和染色体畸变率.在乙蒜素质量浓度为0.032～0.160 g·L-1范围内,微核率随浓度升高而升高,呈一定的剂量-效应关系(r=0.881 9,P≤0.01);而在细菌溴腈质量浓度为0.625～2.5 g·L-1范围内,微核率则呈先上升后下降的趋势.     

链格孢菌毒素细交链孢菌酮酸对蚕豆根尖细胞微核和有丝分裂的影响

利用蚕豆根尖为材料,研究了链格孢菌毒素细交链孢菌酮酸对细胞微核和有丝分裂的影响,以评价其细胞遗传毒性.结果表明,当浓度为12.5～50μg/mL时,细交链孢菌酮酸对蚕豆根尖细胞微核率和有丝分裂指数不产生显著影响,微核率低于3‰,有丝分裂指数超过9.5%.浓度升高到100～400μg/mL时,细交链孢菌酮酸使蚕豆根尖细胞微核率显著升高,有丝分裂指数显著下降,其中,400μg/mL时,微核率高达36.01‰,有丝分裂指数仅为1.90%.当细交链孢菌酮酸浓度为12.5～100μg/mL时,与对照相比,蚕豆根尖细胞多核仁率无显著差异,多核仁率低于3‰;浓度升高到200～400μg/mL时,细胞多核仁率显著升高,400μg/mL时,多核仁率高达26.10‰.     

APM对小麦根尖分生组织细胞异常有丝分裂的诱导

探讨了不同浓度（c／μmol．L－1）和不同处理时间（t／h）下APM对小麦根尖分生组织细胞有丝分裂的影响．实验结果表明，在c（APM）＝1～4μmol／L、处理t＜5h可明显提高有丝分裂指数，对前期和中期细胞分裂的促进作用更为明显；但c（APM）的增加与有丝分裂指数的提高无明显线型关系；APM可促使间期细胞微核形成、中期细胞染色体聚合现象和扰乱纺锤丝的功能．纺锤丝功能上的扰乱可引起细胞的“不均等分裂”和“多极化分裂”形成上述两种细胞异常有丝分裂的临界浓度和处理时间分别为c＝5μmol／L和t＞5h．     

邻苯二甲酸二丁酯对蚕豆胚根细胞微核形成的影响及毒理机制

研究常用增塑剂邻苯二甲酸二丁酯(di-n-butyl phthalate,DBP)对农作物生长的影响,为农用地膜及其残留物的环境安全性评估提供实验依据。以蚕豆为试材,DBP处理浓度为0(CK)、9 mmol·L-1、18 mmol·L-1、27 mmol·L-1和36 mmol·L-1,培养24 h、48 h和72 h后,观测根尖细胞染色体结构变化,测试胚根抗氧化酶活性。结果显示:DBP暴露的蚕豆胚根生长速率减缓;随着DBP暴露时间延长,根尖正在进行分裂的细胞被阻断在有丝分裂前期的比例增加,微核率升高,出现多种类型的染色体畸变;DBP暴露的胚根超氧化物歧化酶(superoxide dismutase,SOD)活性提高5.41%~29.68%,过氧化物酶(peroxidase,POD)活性随DBP浓度增加而递减,过氧化氢酶(catalase,CAT)活性显著降低14.00%~43.08%。结果表明,DBP对蚕豆胚根具有遗传毒性,且能够破坏纺锤丝的结构。     

模拟酸雨及A1^3＋共同作用对蚕豆根尖细胞的遗传损伤

以蚕豆为材料，研究了模拟酸雨及酸雨与铝共同作用的细胞遗传学效应．结果表明，根尖细胞有丝分裂指数随Al^3＋浓度的升高和环境酸度的增强而下降；处理组细胞中出现了多种染色体异常，如染色体粘连、滞后及断裂等．模拟酸雨及其与低浓度Al^3＋（3mg／L）共同作用时可诱发蚕豆根尖细胞微核，其中pH4．5组微核率高于pH3．5组．模拟酸雨与高浓度的Al^3＋（10～180mg／L）复合处理可引起根尖细胞固缩，固缩率随Al^3＋浓度增加和pH降低而增高．研究结果表明，pH4．5和pH3．5的模拟酸雨和Al^3＋对蚕豆根尖细胞具有遗传损伤作用，其效应与Al^3＋浓度和环境酸度有关．     

In-situ monitoring of chromium cytotoxicity in sugarcane

The potential of in-situ monitoring of cytotoxic effects of chromium through root-tip assay was studied in a sugarcane cultivar CoLk 8102 (Saccharum spp. hybrid). Sugarcane setts supplied with graded concentrations of chromium (VI), exhibited a reduction of 85.92 and 95.10 % in mean root length at 40 and 80 ppm Cr dosages along with 61.25 and 82.50% reduction in mean root number/node respectively. Mitotic index of root tip cells of treated setts declined and the frequency of aberrant mitotic phases increased pari passu to the increasing chromium concentration. To compare and quantify the effect of graded chromium dosages on frequency of chromosome aberrations vis-à-vis inhibition of mitotic activity, a 'Decretion factor' (D.F.) has been used for the first time. The value of DF increased with the increase in the chromium dosages. The increase in chromosome aberration frequency was low at low chromium dosages (1 or 2 ppm), but the high Cr dosages (40 and 80 ppm), induced sharp reduction in mitotic efficiency of root system along with anomalies in the process of cell division and induced chromosome aberrations in sugarcane root meristem, which in turn affected the over all plant growth.     

Genotoxicity evaluation of surface waters located in urban area of Xi’an City using Vicia faba bioassays

In this study, micronucleus （MCN） and chromosome aberration （CA） tests in Vicia faba root tip cells were carried out in order to assess the water quality and the comprehensive genotoxic potential of surface waters located in the urban area of Xi＇an City, China. For these evaluations, water samples from different surface waters （four rivers, two lakes, two biological treatment plant effluents） were collected, the ultra-pure water and methyl methanesulfonate solution was used as the negative and positive control, respectively. In our results, highly significant differences in MCN perrnillage （average number of micronuclei per 1000 cells）, CA frequencies and PI （pollution index） values were found among three rivers and two WWTP effluents, the tested samples from two rivers caused the decrease of mitotic index over 22% compared with the negative control. No significant changes were observed in micronuclei and chromosome aberrations frequencies at one river and two lakes during the period of test （wet season）. These results point out a poor state of the water quality and genotoxic activity of the main surface waters in Xi＇an City. It is recommended to establish a monitoring program for the presence of genotoxic agents in these surface waters.     

三叶鬼针草对蚕豆根尖遗传毒性的研究

化感作用是外来植物成功入侵和快速扩散的机制之一,为了探讨入侵植物三叶鬼针草(Bidens pilosa L.)的化感作用机制,运用蚕豆根尖微核技术和植物切片技术,研究了不同质量浓度的三叶鬼针草水浸提液对蚕豆(Vicia faba L.)根尖细胞的遗传损伤和对根生长的影响。结果表明,三叶鬼针草水浸提液对蚕豆根尖细胞有丝分裂及生长产生不同程度的抑制和损伤,具有明显的遗传毒性。水浸提液对蚕豆根尖的影响存在显著的时间效应和质量浓度效应。经切片测量统计,水浸提液促进了成熟区细胞平周分裂,使根尖细胞层数增加;同时显著地抑制了细胞伸长,使根尖缩短,整体表现为使根尖加粗变短。三叶鬼针草水浸提液抑制了细胞有丝分裂的正常进行,并随着水浸提液质量分数的升高,分裂期细胞数目下降,微核率逐渐升高。本研究结果表明三叶鬼针草水溶性化感物质对植物的遗传稳定性及细胞形态结构具有一定的影响,三叶鬼针草的化感作用可能是其成功入侵的机制之一。     

垃圾渗滤液浸种对玉米代际遗传效应的研究

采用实验室早期栽培实验,主要探讨了垃圾渗滤液浸种对玉米代际的遗传效应。结果表明:垃圾渗滤液会影响玉米代际早期的生长发育,低浓度垃圾渗滤液(10%)促进代际玉米种子的萌发及幼苗的生长;而高浓度渗滤液(50%)则对其产生抑制效应。再者,相比于经垃圾渗滤液浸种处理过的F1代玉米种子而言,对F2代产生的毒性效应相对减弱,仅高浓度组与对照组相比出现差异,50%处理组的萌发率、根长、芽长及叶绿素含量分别为对照组的81%,83%,79%和89%。此外,渗滤液浸种对代际玉米根尖细胞有丝分裂均表现出"低促高抑"的作用,对根尖微核损伤也均呈现剂量-效应关系。这说明低浓度垃圾渗滤液对玉米F1代及F2代的生态毒性风险依然存在,不容忽视。研究选用玉米为模式植物具有一定的实际意义,其结果可为垃圾渗滤液的生态风险评价提供理论依据。     

Hg2+胁迫下玉米生理生态变化的研究

通过砂培实验,研究汞胁迫下玉米的生理生态指标包括叶绿素含量、根系活力、游离脯氨酸含量的变化.结果表明,汞对玉米的胁迫是浓度和时间双重因子的作用在低汞浓度、短时间内,叶绿素含量、根系活力及游离脯氨酸含量均有上升的趋势;在高汞浓度、长时间内,各生理指标均严重下降.各生理指标对汞的敏感度略有差异游离脯氨酸含量>根系活力>叶绿素含量;其中脯氨酸含量可以作为汞污染的一个监测指标.     

常乐稀土复合肥对玉米（Zea may L.）的细胞毒性和遗传毒性效应

为了研究常乐稀土多元复合肥对主要农作物--玉米(Zea mays L.)是否产生细胞毒性和遗传毒性效应,采用不同梯度质量浓度的稀土复合肥溶液对玉米进行处理,观察其根尖生长状况,统计分析细胞死亡率、微核率、有丝分裂指数以及对细胞DNA的损伤情况.结果表明,质量浓度为10mg·L-1以下时,常乐稀土复合肥能够促进玉米根尖的生长,100mg·L-1以上时抑制根尖生长;随着试验浓度的递增,细胞死亡率、微核率、DNA损伤率逐渐上升并具有正相关性,表现出明显的剂量-效应关系,而有丝分裂指数却随着浓度的增加逐渐下降.以上结果表明,常乐稀土复合肥对玉米确有一定的细胞毒性和遗传毒性效应,其细胞毒性阈值和遗传毒性阈值皆为100mg·L-1.     

加拿大蓬挥发油经不同载体对蚕豆根尖的细胞毒性

采用悬空气法和土培法,研究了加拿大蓬（Erigeron canadensis L.）挥发油对蚕豆（Vacia faba L.）根尖细胞经不同载体的细胞毒性。结果表明：加拿大蓬挥发油对蚕豆根尖细胞的有丝分裂没有显著的影响,但显著抑制了幼根的生长,使根尖细胞产生了多种类型的染色体畸变,导致微核率升高。综合分析表明,加拿大蓬挥发油经土壤载体的化感作用大于经空气载体的化感作用,推测可能是土壤对挥发油的滞留作用增大了化感效应。     

The investigation of cytotoxic effects of refinery wastewater on root tip cells of Vicia faba L

The present study was carried out to evaluate the cytotoxic effects of refinery wastewater collected from different stations of the Kizilirmak river on Vicia faba L. root tip cells. For this aim, we used the germination percentage, root length, weight gain and micronucleus (MN) frequency as indicators of cytotoxicity. Additionally to the cytological analysis, DNA analyses were performed in root tips meristems of Vicia faba seeds treated with refinery wastewater. Heavy metal concentrations in the water samples were determined using atomic absorption spectrophotometer (AAS). The concentrations of heavy metals in the water were in the order of Pb>Zn>Fe>Cu>Ni>Cd>Hg. The highest germination percantage was observed in the control group (in proportion as 96%). Heavy metals in the water samples collected from Station I, II and III caused a decrease in the germination percentage as 48, 18 and 30%, respectively. The highest root length and weight gain was observed in the control group at the end of the experimental period. The least root length and weight gain was observed in seeds treated with wastewater collected from Station I. In the control group, the weights of all the seeds increased about 4.08 g when compared with initial weight. The root lengths of the control seeds were determined as 6.38 cm at the end of the experimental period. The weights of the seeds exposed to wastewaters obtained from Station I, II and III increased about 1.08, 3.03 and 2.01 g according to initial weight, respectively. Microscopic examination of V. faba root tip meristem cells showed that any example of the MN formation was not seen in the control group. The highest frequency of MN was observed in group treated with wastewater collected from Station I and least frequency of MN was observed in group treated with wastewater collected from Station II. It was also observed that the yields of DNA in the seeds exposed to wastewater were lower than recorded in the controls. Hence, DNA yields exposed to wastewater were run ahead on agarose gel according to the control group. The results clearly indicate that refinery wastewater had important cytotoxic effects on V. faba root tip cells. It was also observed that V. faba seeds are very sensitive and useful biomarkers for monitoring these effects in waters contaminated with heavy metals.