转基因玉米NK603基体标准物质研制

由于转基因标准物质的缺乏,无法保证检测结果的准确、可靠和可比。本研究将筛选后的转基因玉米(Zea mays)NK603 阳性材料及受体进行研磨筛分,粒径测定结果表明,研磨后的粒径大小为 100 μm左右。采用重量法配置了 3 个不同水平的转基因玉米基体物质,应用实时荧光定量 PCR 方法对研制的标准物质进行均匀性和稳定性检测,统计结果表明,所研制的基体标准物质均匀性良好;在 4 ℃保存条件下,一年内未发现不稳定现象。重量法确定的标准值和扩展不确定度(k=2)分别为(0.50±0.10)%、(1.00±0.35)%和(5.00±0.35)%。同时选择 7 家实验室进行协同验证,结果表明,研制的转基因玉米 NK603 基体标准物质量值准确可靠,与国外标准物质相比,不确定度水平相当。本实验研制的转基因玉米 NK603 基体标准物质适用于转基因玉米 NK603 的定量检测。     

转基因产品检测标准物质的定值和不确定度研究进展

转基因产品检测标准物质(genetically modified organisms detection reference materials,GMOs detection RMs)是转基因生物(genetically modified organisms,GMOs)安全监管、转基因产品定性与定量检测、检测方法研究与标准化工作中必不可少的物质基础。为了解决我国转基因产品检测标准物质匮乏的问题,我国启动了"转基因产品检测标准物质研制"研究课题,旨在借鉴欧盟和美国等研制转基因产品检测标准物质的先进经验,建立适合中国国情的转基因产品检测标准物质研制体系,以满足我国转基因生物安全性评价和监管的需求。本研究针对国际上转基因产品检测基体、基因组DNA和质粒DNA不同类型标准物质的研制流程与量值表达方式进行概述,阐述了不同类型标准物质量值不确定度的评定方式,分析目前转基因产品检测标准物质研制中存在的问题,为我国转基因产品检测标准物质的研制提供参考资料,为标准物质的定值和不确定度的评定提供理论依据。     

转基因玉米MON88017转化事件特异性定性PCR检测方法及其标准化

转基因玉米(Zea mays)MON88017是美国孟山都公司通过DNA重组技术开发的具有抗玉米根叶甲虫(Diabrotica virgifera)和抗草甘膦类除草剂特性的玉米品系,本研究的目的是建立该品系的转化事件特异性定性检测方法的标准.根据转基因玉米MON88017的旁侧序列信息,在左边界的结合位点处设计一系列引物组合,在筛选出最佳引物组合后,优化了该引物组合的反应体系,建立了转基因玉米MON88017转化事件特异性定性PCR检测方法.全国7家实验室的验证结果表明,该方法能够特异性检测样品中MON88017转化事件,检测灵敏度均达到0.10%以上,且检测结果具有良好的可重复性、可重现性.本方法符合标准检测特异性强、灵敏度高、重复性好的要求,为我国抗虫耐除草剂玉米MON88017检测和转基因生物安全管理制度的实施提供了相应的技术支撑.     

利用QuantStudioTM 3D数字PCR分析转基因玉米MON863含量

QuantStudioTM 3D数字PCR (QuantStudioTM 3D digital PCR,3D-dPCR)是一种基于超高密度亲疏水微孔芯片实现数字PCR分液原理的新型核酸绝对定量平台,在转基因生物定量领域具有极大的应用前景.本研究基于3D-dPCR平台,以转基因玉米(Zea mays)MON863混合样品为例,建立基于单重和双重数字PCR体系的转基因生物(genetically modified organisms,GMOs)含量分析方法.与传统qRT-PCR比较发现,在缺乏样品纯度、纯合度信息的情况下,数字PCR能够较好地排除这些因素的影响,测定准确的量值.研究结果表明,QuantStudioTM 3D数字PCR是一种适用于转基因生物含量分析的精确定量方法,还可反映转基因玉米种子的基因型.本研究基于3D-dPCR建立的转基因玉米MON863单重和双重定量方法为转基因检测提供了新的方法和参考.     

转基因水稻Bt汕优63的整合结构和品系特异性定量PCR方法

为更好地监测转基因抗虫水稻(Oryza sativa L.)Bt汕优63品系的存在,满足转基因标识管理的要求,同时也为了解决阳性植物基因组DNA不容易获得的问题,本研究采用热不对称交互PCR(TAIL-PCR)、Genome Walking和长链PCR(LD-PCR)方法测定了基因枪转化的转cry1Ab/cry1Ac融合基因水稻品系Bt汕优63的外源插入DNA全序列,构建了含有Bt汕优63 3′旁侧和水稻内标基因gos9序列的标准质粒分子pMDBt63作为标准物质,建立了Bt汕优63实时荧光定量PCR方法.外源插入DNA全长9 818bp,位于水稻基因组10号染色体(AP008214)第5348630位,由8个来源于两个转化质粒的DNA片段组成,其中两个cry1Ab/cry1Ac表达框以正向串连的方式插入.gos9和3′旁侧两个定量标准曲线的相关系数(R2)分别为0.9997和0.9992,扩增效率(E)分别为98.05%和99.46%.每反应100 ng模板DNA的检测限(LOD)为10拷贝,定量限(LOQ)为100拷贝.此外,对已知5%和1%转基因含量的混合样品DNA进行定量检测,结果的平均值分别为4.98%和1.07%.结果表明标准质粒pMDBt63作为标准物质建立的定量方法可用于Bt汕优63的定量检测.     

转基因植物标准物质研究进展

转基因产品的安全性一直都备受关注,因此转基因产品的定性、定量检测越来越重要,而转基因标准物质的使用是转基因产品检测结果有效和可比的重要保证.本文针对国内外转基因植物标准物质的研究现状及相关技术进行综述,重点介绍了转基因植物标准物质的种类、转基因标准物质定值技术,分析了转基因标准物质研制过程中的关键点.更重要的是综述并提出了质粒DNA分子标准物质的定值模式,包括如何合理评价质粒分子可替代性问题,此外还总结了目前国外转基因标准物质的种类,目的是为我国转基因植物标准物质研制和相关研究提供有价值的参考.     

转基因玉米LY038转化事件的特异性检测

转基因高赖氨酸玉米LY038在畜禽饲料中已得到广泛应用,但目前还没有关于其侧翼序列扩增及转化事件特异性定性PCR检测方法方面的报道.本研究采用修饰接头连接PCR(modified adapter-linked PCR,M-AL-PCR)技术获得了转基因玉米LY038的外源基因与玉米基因组之间的5′端侧翼序列.据此侧翼 序列设计其转化事件特异性引物,建立了转基因玉米LY038转化事件特异性定性检测方法,扩增片段175bp.以转基因玉米(Zea mays L.)LY038、MIR604、Bt176、Bt11、MON810、MON863、GA21、NK603、非转基因玉米、转基因水稻(Oryza sativa L.)Cry1C*、Cry2A*、转基因大豆(Glycine max)Roundup Ready和转基因油菜(Brassica campestris L.)GT73为材料,验证该方法具有高特异性及灵敏度,最低检测限约为0.1%.研究结果提示,该定性检测体系可准确、快速、高效的检测转基因玉米LY038及其产品.     

转基因水稻DNA样品浓度以及存放条件对PCR定性检测的影响

通过在不同模板DNA浓度(0.2～16 ng/μL)、不同转基因含量(0.05%～50%W/W)以及不同模板存放温度(22℃、4℃和-20℃)和存放时间(1、2、3周和1,3个月)条件下进行转基因水稻外源成分的定性PCR检测,发现当模板浓度在0.4 ng/μL以上时所有引物均能扩增出目标片段,对于转基因含量为1.0%和0.1%的混合样品,能稳定检测出转基因成分所需的DNA最低浓度分别为1和2～4 ng/μL.模板DNA的不同温度存放条件对检测没有明显影响,长时间存放后PCR扩增产物条带亮度有所减弱.     

转基因棉花MON757转化体特异性PCR检测方法及应用

转基因棉花(Gossypium hirsutum)MON757转化体是孟山都公司研发的转cryIAc基因的抗虫棉,在美国、加拿大、澳大利亚等国被批准种植或允许用作食品饲料原料,但在我国尚未获得批准种植和应用.目前国内外尚没有转基因棉花MON757特异性的纯杂合检测和定量检测方法报道.为了检测我国棉花中MON757转化体的存在情况,本研究以转基因棉花MON757转化体的插入位点基因组序列和外源插入片段/基因组连接区序列为靶标,建立了特异性的MON757转化体纯杂合定性PCR检测方法和实时荧光定量PCR(quantitative real-time PCR,qRT-PCR)检测方法.所建立的MON757转化体纯杂合定性PCR检测方法的检测引物由分别位于MON757外源基因插入位点两侧基因组和外源插入片段上的3条引物组成,能准确地鉴别棉花植株和种子中MON757转化体的纯合、杂合状态.建立的MON757转化体特异性的qRT-PCR检测方法具有良好的可重复性和灵敏度,其检测下限(limit of detection,LOD)为11个拷贝,定量下限(limit of quantitative,LOQ)为44个拷贝.用此方法对2014年湖北省的49份商品棉花种子进行了检测,结果有5份种子样品检测到MON757转化体.采用MON757转化体纯杂合定性PCR检测方法对这5份种子样品各60个单粒分别进行了检测,同时采用qRT-PCR检测方法对这5份种子样品进行定量测定.结果表明,有1份含量在1.5％左右,4份含量超过了20％,两种方法的测定结果基本一致.本研究建立的MON757转化体纯杂合定性PCR检测方法和qRT-PCR检测方法在田间棉花植株和种子中MON757转化体纯杂合状态的测定以及混合样品中MON757转化体含量的测定方面都具有重要的应用价值.     

用巢式和半巢式PCR检测转基因大豆Roundup Ready及其深加工食品*

用从转基因大豆(Glycine max)颗粒中提取的DNA作为模板,经过稀释,形成不同浓度梯度的DNA溶液,然后用巢式和半巢式PCR进行扩增反应。结果表明,巢式和半巢式PCR均可以扩增DNA浓度为10^14g/μL的溶液。用巢式和半巢式PCR对市场的食品原料和深加工食品进行检测,可以从大豆油、酱油、面酱、大豆磷脂、豆腐、豆浆等食品原料和深加工食品的17个品牌的食品中检测出大豆内标基因(housekeeping gene)。其中,2种食品原料和深加工食品的11个品牌的食品中检测出外源基因CaMV35S-CTP4基因片段,说明这些食品中含有转基因大豆成分,占被检测食品的76．5％。用巢式PCR和半巢式PCR检测转基因大豆Roundup Ready和其深加工食品是一种有效的方法。     

低氮和干旱胁迫对富士和秦冠生长及氮素利用的影响

【目的】以富士（Fuji）、 秦冠（Qinguan）嫁接在平邑甜茶（Malus hupehensis Rehd.）上的当年生盆栽苗为试验材料,采用砂培方法,研究了缺氮胁迫和干旱对富士和秦冠生长情况、 光合参数、 植株各部位氮磷钾含量及氮素利用效率的影响,分析比较了低氮干旱条件下富士和秦冠生长及氮素利用的差异,以期为果树生产高效肥水利用提供理论指导。【方法】试验共设四个处理: 正常氮正常水（ZZ）、 低氮正常水（DZ）、 正常氮干旱（ZG）、 低氮干旱（DG）。氮素和水分均设置两个水平,分别为正常氮（6 mmol/L NO-3-N）、 低氮（0.3 mmol/LNO-3-N）、 正常供水（保持盆中砂子相对含水量为饱和含水量的80%~85%）、 干旱处理（保持盆中砂子相对含水量为饱和含水量的60%~65%）。【结果】富士和秦冠的生物量（茎和叶）、 株高茎粗等生长指标以及光合速率、 气孔导度、 蒸腾速率均为正常氮正常水（ZZ）＞低氮正常水（DZ）＞正常氮干旱（ZG）＞低氮干旱（DG）,并且相对应处理下秦冠的以上指标均高于富士;正常供水下,缺氮处理使富士、 秦冠的根冠比比正常氮处理均有所增加,富士提高了2.05%,秦冠提高了22.40%。富士和秦冠的氮、 磷、 钾含量均表现出正常氮正常水（ZZ）＞低氮正常水（DZ）＞正常氮干旱（ZG）＞低氮干旱（DG）; 氮、 钾元素含量在植株各部位的分布顺序依次是叶＞根＞茎,磷元素则是根＞叶＞茎;光合氮素利用效率（PNUE）和氮素利用效率表现为秦冠处理之间差异极显著,富士处理之间差异不显著;秦冠的PNUE和NUE明显高于富士,在低氮正常水（DZ）处理下,秦冠氮肥利用率比富士高42.07%,在低氮干旱（DG）处理下高64.14%;低氮胁迫下富士和秦冠的NUE显著提高,并且秦冠提高的幅度高于富士。【结论】施用氮肥能够显著提高富士与秦冠的干物质量,同等水肥条件下,秦冠生长优于富士;水分亏缺会减少叶片对氮的吸收,干旱条件下适度增施氮肥,可提高果树的抗旱能力;低氮干旱胁迫下秦冠的生长指标、 光合指标及氮素利用效率指标均优于富士,表现出较强的抗低氮干旱胁迫的能力。     

Pasture Vegetation Elemental Analysis by Laser-Induced Breakdown Spectroscopy

Laser-induced breakdown spectroscopy (LIBS) is a new technique for the analysis of plant material. This study investigates the application of LIBS to pasture-based plant samples. The LIBS measurements were obtained from pelletized pasture samples (100 samples) that had been also analyzed by inductively coupled plasma–optical emission spectroscopy (ICP-OES) following microwave digestion for calibration and comparison purposes. Comparisons for elements sodium (Na), potassium (K), magnesium (Mg), calcium (Ca), manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), boron (B), phosphorus (P), and sulfur (S) showed that LIBS could be used for almost all the standard profile total elements with concentrations down to low mg/kg levels (observed error of Na: 0.024 percent, K: 0.18 percent, Mg: 0.016 percent, Ca: 0.073 percent, P: 0.017 percent, Mn: 31 mg/kg, Fe: 150 mg/kg, Zn: 6.6 mg/kg, and B: 1.1 mg/kg). Elemental analysis at less than mg/kg levels was not possible using LIBS. The elements S and Cu were particularly difficult to analyze with reliability using LIBS at the concentration levels found in the plant samples. Replacing microwave digestion and subsequent ICP analysis with a direct analysis of dried plant samples using LIBS has the potential to improve the productivity and reduce the cost of testing.     

Faculty positions:Center for Agricultural Resources Research,Chinese Academy of Sciences

正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology,     

Biodiversity and ecogeography of wild Lactuca spp. in some European countries

Staff members of the Department of Botany of Palacký University in Olomouc and Gene Bank Department – Workplace Olomouc, Research Institute of Crop Production in Prague, Czech Republic, conducted an expedition in seven European countries (Austria, Czech Republic, France, Germany, Italy, the Netherlands, Switzerland) in August/September 1999 to collect wild Lactuca spp. germplasm and study its geographic distribution, ecology and biodiversity. During the mission, more than 600 locations were visited resulting in the collection of 602 seed samples (accessions) of wild Lactuca species and 13 seed samples of related genera (Chondrilla and Mycelis). Lactuca serriola f. serriola, L. serriola f. integrifolia, L. saligna and L. viminea subsp. chondrilliflora were prevalent in southern Europe (Italy, France), however, only L. serriola was common in central and western Europe (Austria, Czech Republic, Germany, Netherlands, Switzerland). The greatest diversity of Lactuca species was found in France, where also the most seed samples (165) were collected. The most characteristic habitats with a high density of Lactuca spp. populations were observed along roads and highways, grassy ditches, ruderal communities, and dust-heaps. Natural infections by powdery mildew (Erysiphe cichoracearum) and downy mildew (Bremia lactucae) on some wild Lactuca spp. were observed. Recent observations concerning the geographic distribution, population structure, habitats, and natural occurrence of diseases of Lactuca spp. are discussed. This assemblage of genetic resources of Lactuca spp. can serve as the basis of future studies of species diversification, spatial population structure, plant microevolution, domestication processes, and genetic variability of host-parasite interactions.     

Macroinvertebrates in North American tallgrass prairie soils: effects of fire, mowing, and fertilization on density and biomass

The responses of tallgrass prairie plant communities and ecosystem processes to fire and grazing are well characterized. However, responses of invertebrate consumer groups, and particularly soil-dwelling organisms, to these disturbances are not well known. At Konza Prairie Biological Station, we sampled soil macroinvertebrates in 1994 and 1999 as part of a long-term experiment designed to examine the effects and interactions of annual fire, mowing, and fertilization (N and P) on prairie soil communities and processes. For nearly all taxa, in both years, responses were characterized by significant treatment interactions, but some general patterns were evident. Introduced European earthworms (Aporrectodea spp. and Octolasion spp.) were most abundant in plots where fire was excluded, and the proportion of the total earthworm community consisting of introduced earthworms was greater in unburned, unmowed, and fertilized plots. Nymphs of two Cicada genera were collected (Cicadetta spp. and Tibicen spp.). Cicadetta nymphs were more abundant in burned plots, but mowing reduced their abundance. Tibicen nymphs were collected almost exclusively from unburned plots. Treatment effects on herbivorous beetle larvae (Scarabaeidae, Elateridae, and Curculionidae) were variable, but nutrient additions (N or P) usually resulted in greater densities, whereas mowing usually resulted in lower densities. Our results suggest that departures from historical disturbance regimes (i.e. frequent fire and grazing) may render soils more susceptible to increased numbers of European earthworms, and that interactions between fire, aboveground biomass removal, and vegetation responses affect the structure and composition of invertebrate communities in tallgrass prairie soils.     

Properties of anaerobically digested and composted municipal solid waste assessed by linking soil mesofauna dynamics and nitrogen modelling

We have studied the effect of anaerobically digested (ADMSW) and composted municipal solid waste (CMSW) on mineralization and foodweb dynamics to verify the hypothesis that ADMSW would immobilize N right after addition to soil in contrast to addition with CMSW. Another hypothesis was that the mesofauna (enchytraeids and microarthropods) would stimulate N release from the decomposer community. We measured excretion of -N and urea-N from the mesofauna and hypothesized that enchytraeids would release urea. ADMSW and CMSW were amended to pots with sandy loam and barley. The pots were divided into treatments with or without mesofauna. Mesofauna, plant N and biomass, soil N and ergosterol (fungal biomass) were measured over a 113-day period of four equidistant samplings. Soil respiration, N mineralization and N release by the mesofauna were modelled from concurrent studies. ADMSW- and CMSW-treated soils initially (<20 days) immobilized N. The amendments did not increase plant growth substantially, and this was probably due to N-limitation in the early stages of plant growth. Enchytraeid abundance was about three times higher in ADMSW- than CMSW-treated soils, indicating that ADMSW contained more labile compounds, bacteria, and microfauna. The mesofauna did not affect N-content, but the cumulated -N excreted by the mesofauna was estimated to be substantial and about one-fifth of total plant N in ADMSW. An explanation for this discrepancy might be that in the absence of the mesofauna, other members of the detrivore and microbivore community performed the mesofauna’s function. Neither enchytraeids nor microarthropods excreted urea.     

Faculty positions: Center for Agricultural Resources Research,Chinese Academy of Sciences

正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology,     

Faculty positions: Center for Agricultural Resources Research,Chinese Academy of Sciences

正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology,     

Variation in quality parameters between and within 14 Nordic tree fruit and berry species

Abstract

A 3-year study was carried out to investigate quality parameters in 14 tree fruit and berry species grown in southern Norway. The species were blueberry, apple, aronia, sour cherry, sweet cherry, red raspberry, strawberry, blackcurrant, gooseberry, red currant and elderberry, harvested along with wild bilberry, cloudberry and lingonberry. Significant differences between species were identified for all quality parameters. The coefficient of variation between species was lowest for pH (12.5%), dry matter (18.9%) and soluble solids (25.3%), followed by titratable acids (59.3%), total phenolics (83.8%), antioxidant capacity FRAP (85.7%) and antiradical power by the DPPH-assay (97.8%), total monomeric anthocyanins (132%) and ascorbic acid (137%). Average coefficient of variation within species were lower and ranged from 4 (pH) to 62% (ascorbic acid). Only the FRAP values were significantly affected by harvesting year with lower levels in 2004 than in 2005 and 2006. There were significant interactions between species and harvesting year for dry matter, soluble solids, pH, ascorbic acid and FRAP. The results indicate generic ranges in composition within species independent upon growing location and climate, and the composition of the tree fruits and berries is not likely to deviate from these ranges. It is concluded that desirable composition of tree fruits and berries and their products should primarily be achieved by selection among species rather than searching fors broadened variation within individual species.     

Potassium Fixation and Release Characteristics in Rhizosphere and Nonrhizosphere Soils for a Rapeseed–Rice Cropping Sequence

Potassium (K) fixation and release in soil are important factors in the long-term sustainability of a cropping system. Changes in K concentration and characteristics of K fixation and release in rhizosphere and nonrhizosphere soils in the rapeseed (Brassica napus L.)–rice (Oryza sativa L.) rotation were investigated using a rhizobox system. The concentrations of different forms of K in both rhizosphere and nonrhizosphere soils decreased with plants compared to without plants, regardless of K fertilizer application. Potassium uptake by crops mainly came from the rhizosphere soil. In the treatment without K fertilizer (–K), the main form of K supplied by the soil to the crops was 1.0 mol L^?1 nitric acid (HNO₃) nonextractable K, followed by nonexchangeable K, and then exchangeable K. In the treatment with K fertilizer (+K), the main K forms supplied by the soil to the crops were exchangeable K and nonexchangeable K. The amount and rate of K fixation after one cycle of the rapeseed–rice rotation was greater in rhizosphere soil than in nonrhizosphere soil. The amount and rate of K fixation of soil in the +K treatment were significantly less than in the –K treatment. The cumulative amounts of K released with 1.0 mol L^?1 ammonium acetate (NH₄OAc) and 1.0 mol L^?1 HNO₃ extraction increased with the increasing numbers of extractions, but the K-releasing power of soil by successive extraction decreased gradually and finally became almost constant. The release of K was less in rhizosphere soil than in nonrhizosphere soil. The release of K in the +K treatment was similar to that in the –K treatment in rhizosphere soil, but the K release in nonrhizosphere soil was greater with the +K than the –K treatment. Overall, the information obtained in this study will be helpful in formulating more precise K fertilizer recommendations for certain soils.