醇溶蛋白水平上甘、青两省春小麦品种间的遗传多样性现状及演变趋势

用APAGE技术检测了43个春小麦品种在醇溶蛋白水平上的遗传变异,在计算Jaccard相似系数的基础上用UPGMA方法进行聚类分析。共得到42种不同的带型,电泳共分离出37条带,其中33条具有多态性。品种间在醇溶蛋白水平上的遗传距离变异范围很大(0．0000～0．8148),平均遗传距离GD=0．5073。说明43个品种在醇溶蛋白编码位点上存在较大变异。聚类结果显示,除佛手麦白成一类外(GS=0．28),地方品种和引进品种与大多数育成品种(GS=0．46)分属不同的亚类,说明育成品种同地方品种和引进品种在醇溶蛋白编码基因上存在较大变异。育成品种间在醇溶蛋白水平上的遗传多样性程度不高,这一结果提示在这一地区进行与醇溶蛋白相关的品质育种很难在现有的育成品种间杂交的基础上取得成功。从遗传多样性的演变趋势来看,历史上以地方品种间醇溶蛋白的遗传变异程度最大(GD=0．5455),50年代引进品种变异程度最小(GD=0．3310)。从60～90年代,育成品种醇溶蛋白水平上的遗传多样性有一先增后减的过程,但总体上变异程度要低于地方品种,其原因与亲本单一和育种目标由高产到优质变化条件下人工选择压由弱到强有关。     

甘、青两省春小麦遗传多样性演变

对甘、青两省自20世纪40年代以来生产上曾大面积应用的200多个春小麦地方品种和育成品种资料进行了分析,结果表明,19个形态性状,5个农艺性状和2个品质性状都存在着广泛的遗传多样性,虽然育成品种农艺性状和品质性状的遗传多样性总体上大于地方品种,但是从20世纪60年代开展春小麦杂交育种工作之后,育成品种形态性状,农艺性状和品质性状遗传多样性呈下降趋势,评价育种对小麦遗传多样性的影响,不能足将地方品种和育成品种的遗传多样性作一简单比较就得出结论,而是应该在遗传多样性演变的动态过程中去研究。     

SSR水平上甘、青两省春小麦品种间的遗传多样性现状及演变趋势

利用22对SSR引物的扩增结果计算品种间的Jaccard相似系数,在此基础上用UP(GMA方法进行了聚类分析,检测了43个春小麦品种间在DNA水平上的遗传变异。22对引物共扩增出102条多态性带,平均每对引物可扩增出4．64条多态性带,具有较好的多态性。SSR水平上43个品种间遗传距离变异范围为0.2222～0.8393,平均遗传距离GD％=0．6055。43个品种聚为两大类,除佛手麦自成一类外,其余42个品种聚为第二大类。聚类结果真实地反映了品种间基因型差异。历史上地方品种间SSR水平上的遗传变异最大,育成品种遗传多样性水平总体上呈下降趋势,且低于地方品种和引进品种。1BL／1RS易位片段特异性引物Rye检测结果显示,共有7个品种含有1RS片段,结果需进一步证实和深入研究。     

甘蔗品种资源的表型遗传多样性

为了提高甘蔗品种资源的利用效率, 为甘蔗遗传育种亲本的选择、杂交组合配制及核心种质构建提供理论指导, 我们利用17个质量性状和5个数量性状分析了来自13个国家共20个地区的1,160份甘蔗品种资源的遗传变异、遗传结构和遗传距离等。结果表明: 5个数量性状在不同来源地品种群体之间的变异系数值(CV)变化较大, 说明不同来源地品种群体的数量遗传变异有较大差异, 其中来自海南的品种其群体遗传变异最丰富。质量性状的Shannon-Wiener多样性指数表明, 来自美国的品种群体遗传多样性最高, 其次为中国台湾, 第三为澳大利亚, 说明上述3个地区的甘蔗种质创新比较活跃, 在遗传育种中使用了更多表型性状多样化的亲本。不同来源地品种其群体的遗传分化系数(Gst)和基因流(Nm)显示甘蔗品种群体表型性状的遗传变异主要来自来源地内部, 且不同来源地品种群体之间存在较大的基因交流。遗传距离和UPGMA聚类分析结果表明, 各来源地品种群体之间遗传距离在0.0261–0.2945之间, 其中以福建和广东的品种最为相似, 其次为古巴和美国、广西和云南、澳大利亚和菲律宾、江西和四川、巴西和法国, 说明上述地区在杂交亲本的选择上比较相近。鉴于此, 在遗传育种中应加大利用具有丰富遗传多样性的品种材料并尽量避免选择同一组的品种相互杂交, 同时对于与其他来源地品种群体遗传距离较远的墨西哥品种群体在亲本选配时应给予更多关注。     

我国主栽一串红资源的表型多样性分析

为了提高一串红品种资源的利用效率,从20个数量性状和5个质量性状方面对我国主栽的20份一串红种质资源的表型遗传多样性进行了研究。结果表明一串红表型多样性丰富,品种间表型性状变异程度较高。外引与中国两个类群间表型变异程度及丰富性都比较相似。25个表型性状的Shannon-Weaver多样性指数变化于0.23~1.97之间,数量性状中以主茎直径、花冠直径、叶柄长、始花时间和花间长的多样性指数较高,质量性状中则以叶面泡状突起程度及叶柄显色强度多样性指数较高。主成分分析筛选出对总体方差累计贡献率达83.96%的前5个主成分,可反映一串红资源的总体形态表现。20份资源间平均遗传距离约为7.0,在欧氏距离约为8.5时,参试的20份资源可分为高生种和矮生种两大类,前者仅包含1个品种(篝火),而后者包含19个品种,且在欧氏距离约为7.2处又可进一步分为4个亚类。     

建国以来我国棉花品种遗传基础的分子标记分析

采用MPD分子标记、遗传距离和聚类分析方法,研究建国以来我国有代表性的166个棉花主栽品种(或品系)的遗传多样性。41个RAPD标记Nei’s遗传距离(GD)与两组不同来源实验数据的表型性状欧氏距离(UD)间相关系数分别为0．6445(n＝1770)和0．7078(n＝7140),表明RAPD可以揭示棉花品种间遗传差异。通过对不同棉种、不同品种类型、不同时期、不同种植区域和不同来源的棉花品种(系)遗传差异的比较,探讨我国棉花品种的遗传基础。各层次上遗传差异的比较表明：在我国主栽棉花品种中,海岛棉品种遗传基础窄于陆地棉品种;我国自育陆地棉品种的遗传基础窄于国外引进品种;杂交陆地棉品种的遗传基础窄于常规品种;上世纪80年代以后陆地棉品种遗传基础窄于70年代品种;长江棉区品种遗传基础窄于黄淮棉区品种,西北内陆棉区品种窄于长江棉区品种。启示我们如何在我国棉花育种的全局和不同层面上把握和制定拓宽棉花育种遗传基础的策略和手段,并为进步深入探讨建国以来我国棉花品种遗传改良规律打下基础。     

基于DUS测试的上海粳稻地方品种遗传多样性分析

利用水稻DUS测试指南(2012版)中的38个水稻标准品种和52个基本测试性状对上海地区的172个粳稻地方品种进行遗传多样性分析,并与14个上海地区选育的申请品种保护的粳稻品种作比较。结果表明:地方品种表型性状共检测到176个等位变异,平均每个测试性状检测到3.6667个,变幅介于1~8个。Shannon's多样性指数(H')平均值为0.6834,变幅介于0~1.9327,77.08%的性状存在3个及以上的等位变异;地方品种的等位变异数、每个性状的等位变异数及其变异幅度、多样性指数平均值等均大于现代育成品种,在外观形态上,地方品种的遗传多样性比现代育成品种更丰富。利用UPGMA法进行聚类分析发现在相似系数为0.53时,可将186个粳稻品种分为3个类(亚)群,现代育成品种单独组成一个亚群;而主坐标分析将186个粳稻品种明显的分为地方品种和现代育成品种两大区。地方品种具有丰富的多样性,与现代育成品种具有明显的形态差异,可为今后粳稻育成品种的改良提供更多的形态基础。     

东北地区谷子地方品种和育成品种表型比较分析

我国东北地区谷子育种经历了从地方品种到育成品种的转变,但其具体表型性状等变化尚不清楚。本研究在敖汉旗对我国东北地区120个谷子地方品种和育成品种进行表型鉴定,并分析了遗传多样性,结果表明:东北地区谷子品种以绿幼苗、绿叶鞘、纺锤松散穗、黄粒、黄米型为主。育成品种晚熟、生物量大且高产,表现在出苗至抽穗、开花、成熟的时间以及播种至成熟的时间均极显著大于地方品种;主茎直径、叶片数、旗叶宽度均极显著大于地方品种;主穗重、主穗粒数极显著大于地方品种,主穗粒重和产量显著大于地方品种,但千粒重极显著小于地方品种,说明育成品种主要通过增加穗粒数来实现产量提升。遗传多样性指数分析发现,参试品种各性状遗传多样性指数大小顺序为:产量性状(2.0063)形态性状(1.9655)生育期(1.7238)质量性状(0.6370);地方品种护颖颜色、粒色、米色遗传多样性指数明显高于育成品种,说明谷子育种使粒色米色越来越趋于一致。基于30个性状的标准化数据,将参试品种聚为两类,聚类结果与品种来源地没有明显关联。类群Ⅰ为早熟、低产品种,且幼苗叶色、米色均为绿色和黄色;类群Ⅱ为晚熟、高产品种。根据10个主要表型性状,筛选出综合性状优良的红谷子、燕谷18等种质资源,可供东北地区谷子育种重点利用。     

谷子地方品种和育成品种的遗传多样性研究

对河南、河北和山东等地的482份谷子地方品种和近30年培育的谷子品种的11个形态性状和农艺性状进行种植观察,研究两类品种的遗传多样性。与地方品种相比,育成品种形态性状的多样性指数大多低于地方品种,育成品种的株高比地方品种显著降低,稳重、穗粒重和出谷率等性状显著提高。地方品种的广泛变异类型是现代谷子育种的重要遗传资源。     

滇牡丹天然居群的遗传多样性分析

以云南中部及西北部的6个滇牡丹(Paeonia delavayi)天然居群为研究对象,进行株高、新枝长等9个表型性状的表型多样性分析和ISSR分析。结果表明:9个表型性状变异幅度为0.9%~39.8%,平均值达到了18.9%;居群间生殖器官的变异较大,居群内营养器官更容易产生变异。利用居群间欧式距离进行聚类分析,6个居群聚为4个类群,没有与实际地理位置相吻合,说明表型特征的性状与地理距离的相关性不大。遗传多样性分析结果表明:利用筛选得到的10条引物,在取自6个自然居群、180个个体中,检测到56个多态位点。在居群水平上,多态位点百分率(PPB)为60.2%,Nei's基因多样性指数(H)和Shannon's信息指数(I)分别为0.281和0.414。在物种水平上,Nei's基因多样性指数(H)和Shannon's信息指数(I)分别为0.409和0.596。居群间的遗传分化系数(Gst)达0.319。结果显示,表型性状在居群间和居群内均存在广泛变异。滇牡丹遗传多样性水平较高,居群间遗传分化较大,滇牡丹并不濒危。     

影响水稻光合日变化的酶和相关因素的分析

水稻叶片的最大光合速率出现在上午１０：００时,Ｒｕｂｉｓｃｏ初始活力也在此时达到最大,然后逐渐降低,下午１４：００时略上升后又下降．Ｒｕｂｉｓｃｏ初始活力与光合速率之间极显著相关,相关系数为 ０．９４７４．运用相关性分析、回归分析、通径分析,对晴（有时有云）天气水稻叶片的光合速度、光合关键酶及有关因素的日变化进行综合评估,结果发现中午光合下降主要来自气孔限制,同时Ｒｕｂｉｓｃｏ活性也下降;Ｒｕｂｉｓｃｏ活性是影响光合日变化的又一重要生化因子．体内Ｒｕｂｉｓｃｏ活性受Ｒｕｂｉｓｃｏ活化酶的调节．     

凡纳滨对虾各月龄性状的主成分与判别分析

为了研究凡纳滨对虾各性状增长规律和判定最佳生长季节凡纳滨对虾的体格与月龄的关系,选择1～6月龄凡纳滨对虾各1000只,选择全长、体长、第一腹节背高、第三腹节背高、第一腹节背宽、头胸甲长和体重共7个性状,进行主成分与判别分析.结果表明:各月龄凡纳滨对虾性状之间均呈现显著的正相关(P<0.01), 其中以全长与体长的相关性最为明显,1月龄凡纳滨对虾体重与形态性状的相关系数较小.各月龄凡纳滨对虾的主成分有所不同,1～2月龄凡纳滨对虾的第一主成分为长度因子,第二主成分为宽度因子,第三主成分为高度因子;3月龄凡纳滨对虾的第一主成分与1～2月龄凡纳滨对虾一致,但第二主成分为高度因子,第三主成分为体重因子;4～6月龄凡纳滨对虾的第一主成分为体重因子,第二主成分为高度因子,第三主成分为宽度因子.1～3月龄凡纳滨对虾形态性状的增长优先于体重, 4～6月龄凡纳滨对虾体重优先于形态性状的增长.错过最佳生长季节的凡纳滨对虾的与体格大小相符的月龄可通过建立的判别式来判断,总的判别准确率为98.98%,其中2～4月龄凡纳滨对虾的判别准确率为100%.     

Dna Ploidy Studies of Benign and Malignant Tumours: Comparison of Flow Cytometry and Image Analysis Techniques Using Two Types of Cytological Specimen

DNA ploidy studies were carried out on Feulgen stained smears and cytocentrifuge preparations from 35 malignant tumours and four benign neoplasms using the CAS image analyser. The smears were prepared from scrapings from fresh tumour tissue whereas the cytocentrifuge preparations were prepared from single nuclear suspensions from paraffin-embedded cell blocks from the same tumour. Histograms obtained by image analysis of the tumour scrapes were compared with those obtained on the cytocentrifuge preparations. Concordant results were obtained in four benign tumours (100%) and 32 malignant tumours (91%). The results obtained by image analysis were also compared with results obtained by flow cytometry of the tumour tissue. Discordant results were obtained for three malignant tumours. Possible reasons for the discrepancy include sampling error, tumour heterogeneity and selective loss of cell populations during processing.     

Comparison of the Halving of Tablets Prepared with Eccentric and Rotary Tablet Presses

The aim of this study was to compare the densification of powder mixtures on eccentric and rotary tablet presses and to establish relationships with the halving properties of the resulting scored tablets. This is an important problem because the recent guidelines of EU require verification of the equal masses of tablet halves. The models of Walker, Heckel, and Kawakita were used to describe the powder densification on the two machines. The calculated parameters revealed that the shorter compression cycle of rotary machines results in poorer densification and lower tablet hardness at a given compression force. This is manifested in poorer halving properties, which are influenced mainly by the hardness. Better densification improves the halving even at lower tablet hardness. This demonstrates that these parameters can be good predictors of tablet halving properties.     

Fish ecoregions of Kansas: stream fish assemblage patterns and associated environmental correlates

Synopsis Principal components analysis was performed on fish presence/absence data for 39 common fish species from 410 stream sites in Kansas. The analysis confirmed ten ecologically meaningful fish assemblages, based on species associations. Factor scores based on these assemblages were then clustered into six geographic areas or fish ecoregions. Canonical discriminant analysis identified environmental variables that distinguished the derived fish ecoregions. Mean annual runoff, mean annual growing season, and discharge appear most important. Mean width, mean depth, chloride concentration, water temperature, substrate type, gradient, and percent of pool habitat were less important. Correspondence exists between these fish ecoregions and the patterns of physiographic regions, river basins, geology, soil, and potential natural vegetation in Kansas. The multivariate statistical approach used to classify fish ecoregions should have considerable potential value for fish assessment and management purposes in areas other than the state of Kansas.     

Discrimination of higher plant calluses based on embryogenic capacity and taxonomic classification by pyrolysis mass spectrometry

Pyrolysis mass spectrometry (PyMS) is a rapid, simple, high-resolution analytical method based on thermal degradation of complex material in a vacuum, and has been widely applied to the discrimination of closely related microbial strains. Minimally prepared samples of embryogenic and non-embryogenic calluses derived from various higher plants (sweet potato, morning glory, Korean ginseng, Siberian ginseng, and balloon flower) were subjected to PyMS for spectral fingerprinting. A dendrogram based on the unweighted pair group method, with arithmetic mean of pyrolysis mass spectra, divided the calluses into Siberian ginseng embryogenic callus and the others, which were subsequently divided into embryogenic and non-embryogenic callus groups, regardless of plant species from which the calluses were derived. In the non-embryogenic callus group, the dendrogram was in agreement with the known taxonomy of the plants. These results indicate that PyMS analysis could be applied for discriminating plant calluses based on embryogenic capacity and taxonomic classification.     

Pluralism and diversity: trends in the use and application of ordination methods 1990‐2007

Question: What are the trends and patterns in the application of ordination techniques in vegetation science since 1990? Location: Worldwide literature analysis. Methods: Evaluation of five major journals of vegetation science; search of all ISI‐listed ecological journals. Data were analysed with ANCOVAs, Spearman rank correlations, GLMs, biodiversity indices and simple graphs. Results: The ISI search retrieved fewer papers that used ordinations than the manual evaluation of five selected journals. Both retrieval methods revealed a clear trend in increasing frequency of ordination applications from 1990 to the present. Canonical Correspondence Analysis was far more frequently detected by the ISI search than any other method. Applications such as Correspondence Analysis/Reciprocal Averaging and Detrended Correspondence Analysis have increasingly been used in studies published in “applied” journals, while Canonical Correspondence Analysis, Redundancy Analysis and Non‐Metric Multidimensional Scaling were more frequently used in journals focusing on more “basic” research. Overall, Detrended Correspondence Analysis was the most commonly applied method within the five major journals, although the number of publications slightly decreased over time. Use of Non‐Metric Multidimensional Scaling has increased over the last 10 years. Conclusion: The availability of suitable software packages has facilitated the application of certain techniques such as Non‐Metric Multidimensional Scaling. However, choices of ordination techniques are currently less driven by the constraints imposed by the software; there is also limited evidence that the choice of methods follows social considerations such as the need to use fashionable methods. Methodological diversity has been maintained or has even increased over time and reflects the researcher's need for diverse analytical tools suitable to address a wide range of questions.     

Chemometric evaluation of the anti-cancer pro-drug podophyllotoxin and potential therapeutic analogues in Juniperus and Podophyllum species

Introduction – Podophyllotoxin, deoxypodophyllotoxin, demethylpodophyllotoxin and podophyllotoxone are four therapeutically potent secondary metabolites. There is a dearth of information on the holistic analysis of their distribution pattern in both phylogenetic and ecological contexts. Objectives – To analyse the continuum of the above metabolites in Juniperus and Podophyllum species collected from natural populations in Himalayan environments and the botanical gardens of Rombergpark and Haltern (Germany) using multi‐component LC‐ESI‐MS/MS, coupled with statistically relevant chemometric assessment. Methodology – We evaluated the individual and holistic metabolite profiles and chemometrically correlated the phytochemical loads between various species (infraspecific), organic and aqueous extracts, and populations of the same species from different locations, different species from same location, different species from different locations and infrageneric populations from same and different locations. Results – Multivariate analysis revealed Juniperus x‐media Pfitzeriana as a suitable alternative to Podophyllum hexandrum for commercial exploitation. A significant positive correlation of podophyllotoxone with both podophyllotoxin and demethylpodophyllotoxin, and a negative correlation of podophyllotoxin with both deoxypodophyllotoxin and demethylpodophyllotoxin (infraspecific among Podophyllum), were observed by Kruskal's multidimensional scaling and corroborated by principal component analysis, indicating probable similarity and/or difference between the biosynthetic pathways, and synergistic and/or antagonistic principles, respectively. Finally, linear discriminant analysis and hierarchical agglomerative cluster analysis revealed considerable infrageneric and infraspecific variability in secondary compound spectra and load of the different populations under study. Conclusion – Such holistic studies of plants and their therapeutic metabolites ought to assist in selecting plants, geographical areas and environmental conditions for bioprospecting and global‐scale phytochemical and phylogenetic diversity studies in the future. Copyright © 2010 John Wiley & Sons, Ltd.