巴西橡胶树树根组织培养外植体消毒研究

[目的]寻找一条降低橡胶树树根组织培养中外植体污染的有效途径。[方法]对巴西橡胶树树根进行组织培养,取林段断根处理30d后的新根为外植体,采用1g/L多菌灵、0.1%HgCl2和不同浓度益培隆对其进行了消毒试验。[结果]在常规消毒前先采用1g/L多菌灵对外植体处理2.5h,再用75%乙醇消毒30s及0.1%HgCl2消毒6min,然后接种到添加0.1%益培隆的固体愈伤诱导培养基上,培养30d后外植体污染率下降至44.59%,存活率达25.60%。[结论]该研究为降低橡胶树树根组织培养中外植体污染提供了理论依据。     

Deoxynivalenol in wheat milling fractions: A critical evaluation regarding ongoing and new legislation limits

New maximum limits (ML) for deoxynivalenol (DON) in wheat and its products were set in Brazil in 2017, and new changes are scheduled for 2019. The concentration of DON in wheat and milling fractions (bran, shorts, break flour, reduction flour) was evaluated in samples from commercial fields to discuss the effects of the new legislation. Cleaned wheat samples contaminated with DON had concentrations ranging from 308 to 2373 ng g⁻¹ (n = 29), and one sample had a concentration of 3426 ng g⁻¹. DON concentration obtained in bran and shorts were significantly higher than that of the flours. Compared to the initial concentration in cleaned wheat, DON relative concentrations were 73 and 35% higher in bran and shorts, respectively, and 67% lower in the straight run flour (break plus reduction flour). The bran and straight run flour contained DON concentrations that were 62.1 and 17.2% respectively higher than that of the ML set in Brazil in 2017; additionally, these values would reach 65.5 and 34.5%, respectively, according to the changes to be in effect in 2019. The present study demonstrates DON distribution in wheat milling fractions, thus, providing updated information for the management of DON contamination for the industry and policymakers.     

降低茄子茎段组培染菌率的初步研究

茄子茎段组培容易染菌,为了测试15种灭菌方法的灭菌效果,选取紫圆茄、紫长茄、绿茄3种类型茄子品种,根据染菌率和植株再生成活率判断最佳灭菌方法。结果表明,不同类型茄子适用的灭菌方法不同。紫圆茄茎段适宜的灭菌方法为:2%Na Cl O浸泡10min,再用0.1%Hg Cl2浸泡10min;紫长茄茎段适宜的灭菌方法为:4%Na Cl O浸泡10min,再用0.3%Hg Cl2浸泡10min;绿茄茎段适宜的灭菌方法为:6%Na Cl O浸泡10min,再用0.1%Hg Cl2浸泡10min。绿茄茎段保存试验结果表明,低温保存有利于降低茄子茎段组培染菌率,其中最适保存条件为5℃下保存3d以内,染菌率在20%以下,再生成活率保持在60%左右,可以满足植株再生要求。     

南淝河水及沉积物中的重金属污染评价

分析,评价了南淝河水及其沉积物中的重金属含量状况。结果表明,南淝河河水重金属含量较低,属国家地面Ⅱ类标准,但沉积物中的重金属污染严重,是河流背景值的几倍甚至几十倍。南淝河下游两岸合肥市工业区是污染产生的主要污染源。     

工厂化生产组培苗的污染及其控制研究

每月对组培环境空气中污染菌、组培苗污染监测表明:组培苗污染程度与组培环境空气中的真菌数量均随时间呈同步变化;组培环境空气中真菌主要有12种,其中,优势菌为芽枝霉、灰霉、木霉、曲霉、青霉等5种。甲醛熏蒸可使组培环境空气中的真菌减少87%～100%。     

酒精消毒液污染解淀粉芽孢杆菌的临床生物学调查

目的:在医院感染监测中发现75%酒精消毒液被解淀粉芽胞杆菌污染,检测与分析解淀粉芽孢杆菌的生物学特性,为防止临床常用75%酒精消毒剂的污染及医院感染而提供消毒灭菌方法与实验依据。方法:按照《消毒技术规范》标准进行细菌总数检测;用VITEK-32型全自动细菌鉴定仪检测细菌;常规方法检测该细菌对理化因素的抵抗力;K-B法进行药物敏感性试验。结果:追踪到医院制剂室75%乙醇消毒剂中培养出同一种细菌,细菌总数>800 cfu/mL,鉴定为解淀粉芽孢杆菌。该细菌耐煮沸5 min,在95%乙醇中生长良好,对1∶50的84消毒液和臭氧等均不敏感;而紫外线照射30 min、250 mg/L健之素作用5 min及高压灭菌等对其有较好的杀灭作用;对常用的13种抗生素敏感,7种抗生素耐药。结论:75%乙醇消毒液容易受到解淀粉芽胞杆菌的污染,配制时应对容器及空气环境进行严格地消毒灭菌,杀灭细菌芽胞应选用适宜的消毒灭菌方法。     

采矿活动对煤矿区土壤中重金属污染研究

以国家亿吨煤建设基地、已有百年开采历史的淮南矿区为例 ,研究长期采矿活动 (尤其是煤矸石堆积 )造成的矿区土壤重金属污染。从不同开采历史的 3个矿井区 (大约分别为 10 0、5 0、2 5年 )选择 4条土壤采样线 ,系统采集煤矸石堆附近的土壤样品 ,使用美国IRISIntrepid电感耦合等离子体全谱直读光谱仪对土壤中主要有害元素 (Cu、Ni、Pb、Zn、Sn、Cr、Co)进行分析 ,用土壤标样 (GBW0 74 0 3)控制分析质量。采用元素富集系数法 (Al为参比元素 )来评价重金属的富集水平。研究结果表明 :矿区土壤已表现来自采矿活动的重金属污染贡献 ,且具有累积性。不同矿井区土壤中重金属含量呈现随开采历史及堆积煤矸石风化时间长而递减的趋势 ,且Co、Cu、Zn、Ni、Pb表现相对较强的迁移性 ,其含量在部分矿井区土壤中超过国家土壤一级污染标准。但矿区土壤中分析的重金属元素均未超过国家土壤二级污染标准 ,这说明煤矸石中重金属向周围土壤的迁移是缓慢过程     

葫芦岛市连山区、龙港区土壤重金属空间分布及污染评价

本文利用地理信息系统及地统计学,对葫芦岛市连山区和龙港区土壤中重金属的污染状况进行了空间变异性分析,对Cd、Cu、Zn污染进行单因子评价。结果表明:土壤Cd、Cu、Zn的理论模型均为球状模型。Cu的C0/(C0+C)为26%,说明Cu体现为中等的空间相关性,Cd、Zn的C0/(C0+C)分别为0.3%、3.2%,说明这2种重金属体现为强烈的空间相关性。在已有监测数据的基础上,制作了该地区土壤Cd、Cu、Zn污染的预测表面,得到研究区土壤重金属的分布图及污染分布图。研究表明,龙港区和杨杖子矿区的土壤已达到了重度污染的水平,不再适合于农业生产。     

Mine waste contamination limits soil respiration rates: a case study using quantile regression

We present an application of a statistical approach, quantile regression (QR), which identifies trends in soil processes otherwise masked by spatial and temporal variability. QR identifies limits on processes and changes in the variance of a response along an environmental gradient. We quantified in situ soil respiration, pH, and heavy metal concentrations across a mine waste contamination gradient that spanned greater than an order of magnitude of metal concentrations. Respiration values were monitored at study sites over 2 years. We used QR to show that soil respiration was limited with respect to both heavy metals and pH, and that both increased metals and increased acidity constrained variation in soil respiration values. Maximum respiration values declined by 48% over the Metals Contamination Index (MCI) range and by 72% over the pH range. The use of QR avoided the necessity of discriminating between multiple sources of variation in a spatially and temporally variable system. It is often unrealistic or too time consuming and expensive to attempt to measure all of the relevant predictor variables in the field. The simpler approach offered by QR is to explore factors that limit a process, recognizing that not all of the factors contributing to a soil function will be measured. An application of this approach to the evaluation of a mine waste remediation procedure is discussed.     

可降解络合剂及微生物调控对海州香薷修复污染土壤的效应

盆栽试验研究了海州香薷在Cu、Zn、Pb污染土壤上生长和对Cu、Zn、Pb的富集能力,以及调控剂EDDS、壳聚糖和微生物菌剂对海州香薷重金属吸收的影响。结果表明,Cu223mg/kg,Pb232mg/kg,Zn1068mg/kg的重金属复合污染土壤对海州香薷的生长发育没有明显影响。施用EDDS(3mmol/kg土) 微生物制剂处理组海州香薷叶片中Cu含量高达847mg/kg,Zn含量为745mg/kg;Cu吸收量高达6244μg/株,Zn吸收量为5670μg/株,叶片中Cu、Zn的含量和吸收量均极显著高于对照(p<0.01);3mmol/kg土EDDS处理海州香薷茎中Pb含量显著增加(p<0.05),茎中Pb的吸收量亦显著提高(p<0.05),茎秆中Pb的吸收量为274μg/株。微生物制剂或壳聚糖单独处理对海州香薷生长和金属元素吸收均没有明显的效果。