浙南柚类地方资源遗传多样性分析和鉴定

利用SRAP标记对13份浙南柚类地方资源和琯溪蜜柚及芽变进行遗传多样性分析和鉴定。结果表明:平均每个引物组合可扩增出15.7条谱带,14对SRAP引物共产生220条谱带,其中多态性谱带为122条,多态率为55.4%,表明15份材料间检测到的SRAP位点多态性不高,不同引物组合可将11个基因型完全分开。聚类分析结果显示,15份柚类种质在遗传相似系数0.97处可以分为8大类,第1类群为四季柚7个优异株系,第2类群包括琯溪蜜柚及其芽变,而平阳文旦、早香柚、处红柚、红心1号土柚、红心2号土柚、酸柚分别单独为第3、4、5、6、7、8类群。四季柚选系中务城1号、务城3号、马站红心四季柚的指纹图谱有可区分的差异,说明DNA水平发生轻微变异。     

柚类种质资源分类鉴定初步研究

结合柚的形态与生理生化指标进行主成分分析,对柚的传统分类进行了综合评价,证明传统分类的内在合理性;参照RAPD分子标记研究结果,将传统分类与分子系统分类相对照,对柚类种质资源的分类鉴定进行了初步讨论与分析,可以看出,将传统分类方法与分子标记技术结合起来,更能科学有效地分类鉴定柚类种质,指导生产实践.     

柚品种的等位酶变异研究

研究了柚的48个品种的等位酶变异,利用等位酶分析技术对柚的酯酶（EST）,6－磷酸葡萄糖异的酶（PGI）,6－磷酸葡萄糖变位酶（PGM）,莽草酸脱氢酶（SKD）,超氧化物歧化酶（SOD）共5个酶系统的10个等位酶基因座进行了分析,除PGI－1,PGI－2两个基因座外,其它8个均为多态性基因座;10个等位酶基因座共观察到的等位基因25个,平均每个基因座的有效等位基因数目为1．55,基因多样度0．2805,柚的品种间具有较为丰富的等位酶标记遗传多样性,但柚类种质资源群体总的遗传多样性水平偏低。柚的较低的有效等位基因数目与基因多样度可能由于人工选择及资源流失造成。     

黄麻种质资源遗传多样性的SRAP分析

为明确黄麻(Corchorus L.)种质资源的遗传多样性,采用SRAP分子标记方法,对来自13个国家的两个黄麻栽培种及野生种共96份黄麻种质资源进行了分析。研究结果如下:(1)供试黄麻种质资源之间的遗传距离在0.0169至0.9667之间,变幅较大,其中近缘野生种与其他种质的遗传距离最大,基本在0.8以上;圆果栽培黄麻与其他种质的遗传距离最小,平均<0.5。(2)当在聚类图上遗传距离为0.53处划切割线L₁时,96份黄麻种质资源被分为两个大类群(Ⅰ、Ⅱ)、一个小类群(Ⅲ)和5个独立个类。(3)当在遗传距离为0.33处作切割线L₂时,各大类群被分为不同的亚类群,并表现出按地域聚类的趋势。(4)供试黄麻种质资源基于SRAP分子标记的聚类与形态学上的表现并不完全一致。     

保留特殊种质材料的核心库构建方法

本研究提出了能保留特殊种质材料的多次聚类构建种质资源核心库方法,对种质材料的表现型数据采用合适的遗传模型及混合线性模型统计分析方法无偏预测基因型值,用基因型值构建核心库,计算材料间的马氏距离,用不加权类平均法进行聚类,根据聚类图选取材料构建核心库时,优先保留特殊遗传材料,用方差F测验、均值t测验、极差比和变异系数评价核心库代表原有种质资源群体遗传多样性的程度,以168个棉花基因型的5个纤维性状构建核心库。     

水稻种质资源及其在功能基因组中的应用

水稻种质资源群体分为自然种质资源和遗传资源两类,是作物遗传改良和功能基因组学研究的基础材料。现简要介绍利用水稻种质资源群体开展全基因组关联分析定位数量性状位点、剖析基因变异与功能多样性、发掘与利用有利基因、分析基因组多样性及驯化选择区域等方面的研究进展及其展望。     

燕麦种质资源形态学性状的遗传多样性

【目的】燕麦种质资源遗传多样性研究不仅有助于种质资源的收集和评价,而且对燕麦生产和育种具有重要指导意义。【方法】研究对260份燕麦种质资源的20个形态学性状多样性、变异及聚类进行分析,评价其形态学性状的遗传变异水平,明确燕麦种质资源的性状特点与遗传多样性,以期为燕麦种质创新和品种改良提供依据。【结果】260份燕麦种质资源形态学性状间存在广泛的遗传多样性,质量性状的遗传多样性指数以粒色最大(1.53),芒色最小(0.76);12个数量性状呈正态分布,数量性状的遗传多样性指数以千粒重最大(2.03),有效分蘖数最小(1.22),变异系数最大的是有效分蘖数(89.02%),最小的是株高(11.19%)。根据燕麦品种(系)间各性状的遗传差异,聚类分析将供试的260份燕麦种质资源分为6类,其中种质群Ⅰ包括42份材料,可作为种用型育种目标的亲本材料;种质群Ⅱ包括31份材料,可作为选育高产饲草品种的亲本材料;种质群Ⅳ包括41份材料,可作为选育大粒专用型品种的育种材料;种质群Ⅴ包括46份材料,可作为燕麦矮化的亲本材料;而种质群Ⅲ包括46份材料,种质群Ⅵ包括54份材料,这两类种质群材料的综合性状表现不突...     

橄榄ISSR和RAPD遗传多样性分析和核心种质构建

为揭示中国橄榄(Canarium album)种质资源的遗传多样性,采用ISSR和RAPD标记对橄榄主要分布区的86份种质资源进行遗传多样性分析并构建核心种质.结果表明,基于UPGMA遗传相似系数,86份种质资源可分为3个大类;基于STRUCTURE模型聚类,可分为4个类群,这基本符合橄榄的地域性分布规律.采用ISSR...     

基于ISSR技术研究诺丽种质资源的亲缘关系

为探讨我国诺丽(Morinda citrifolia)种质资源的亲缘关系,采用ISSR技术对诺丽种质资源的遗传关系进行分析。结果表明,10条ISSR引物对13份诺丽种质资源共扩增出183条带,其中多态性条带有159条,占86.9%。13份诺丽种质的遗传相似系数为0.464~0.784。聚类分析将13份诺丽种质资源聚为两类,其中诺丽小黑种单独聚为一类,与其他12份诺丽种质资源的亲缘关系较远。虽然按照外部形态特征不能将所有诺丽种质完全区分,但具有相同特征的多数种质还是聚在同一类或亚类中。     

慈姑种质资源表型性状多样性分析

对保存在国家种质武汉水生蔬菜资源圃内慈姑41份地方品种、26份野生资源的遗传多样性进行了分析。结果表明:各性状多样性指数均较大,数量性状遗传多样性指数(1.840～2.039)高于质量性状(1.033～1.382),说明这些慈姑种质资源具有广泛的遗传多样性,且数量性状遗传变异更丰富;与慈姑种质资源产品相关的性状变异系数较高(24.16%～62.01%),利用现有资源选育球茎大、产量高的品种成为可能。基于慈姑资源13个表型性状的聚类分析,将67份慈姑种质资源分为3类,第Ⅰ类为野生资源类群,该类可进一步分为3个亚类,第Ⅱ类为栽培黄慈姑类群,第Ⅲ类为栽培乌慈姑类群,该类亦可进一步分为2个亚类,大类或亚类间亲缘关系较远,在慈姑杂交育种时宜选择类群间或者亚类间的材料为亲本。     

Amphibian Temperature Regulation Studies in the Field and Laboratory

Studies on thermoregulation in the laboratory and field havecome a long way from the early work done between 1940 and 1960.While some physiological studies on amphibians have progressedat the same rate as those on reptiles, field studies have beenfar behind. Laboratory studies have largely delt with thermalacclimation, evaporative water loss, and thermal and moisturegradient behavior. Field studies, following early summariesof body temperatures of field animals, have stressed behavioralthermoregulation; yet, detailed studies on behavioral thermoregulationin amphibians have been completed for only a handful of species.A few studies have placed behavioral and physiological thermoregulationinto an ecological or energetic framework; these studies arereviewed, and suggestions are made for future work.     

造礁石珊瑚群落结构研究的概况,问题和前景

造礁石珊瑚作为珊瑚礁生态系统中的关键生物类群,其群落结构是珊瑚礁系统研究中的一个重 要方面。本文回顾了20余年以来世界各国对造礁石珊瑚群落结构研究所取得的主要进展和认识,指出了目前研究中存在的问题并分析了不同空间范围研究结论之间的缺乏一致性和中等干扰假说的不足。 最后,结合珊瑚礁生态系统基础理论和应用发展的需求,本文探讨了造礁石珊瑚群落结构研究的前景。     

Leisure activities, cognition and dementia

Accumulated evidence shows that leisure activities have a positive impact on cognitive function and dementia. This review aimed to systematically summarize the current evidence on this topic taking into account the limitations of the studies and biological plausibility for the underlying mechanisms linking cognition, dementia and leisure activities, with special attention on mental, physical and social activities. We included only longitudinal studies, with a follow-up time of at least 2 years, published in English from 1991 to March 2011 on leisure activities and cognition (n = 29) or dementia (n = 23) and provided some evidence from intervention studies on the topic. A protective effect of mental activity on cognitive function has been consistently reported in both observational and interventional studies. The association of mental activity with the risk of dementia was robust in observational studies but inconsistent in clinical trials. The protective effect of physical activity on the risk of cognitive decline and dementia has been reported in most observational studies, but has been less evident in interventional studies. Current evidence concerning the beneficial effect of other types of leisure activities on the risk of dementia is still limited and results are inconsistent. For future studies it is imperative that the assessment of leisure activities is standardized, for example, the frequency, intensity, duration and the type of activity; and also that the cognitive test batteries and the definition of cognitive decline are harmonized/standardized. Further, well designed studies with long follow-up times are necessary. This article is part of a Special Issue entitled: Imaging Brain Aging and Neurodegenerative disease.     

Review of the mutagenicity/genotoxicity of butylated hydroxytoluene.

Butylated hydroxytoluene (BHT) is an effective, widely used, low cost antioxidant. A host of studies examining the potential of BHT to cause point mutations have been published. They include in vitro studies on various bacterial species and strains and on various types of mammalian cell lines as well as in vivo studies on Drosophila melanogaster, silk worms and also the mouse specific locus test (involving long-term exposure). Together these studies convincingly show the absence of a potential for BHT to cause point mutations. A great number of studies on many cell types and species have also been carried out to examine the potential of BHT to cause chromosome aberrations. In vitro studies have been published using plant cells and the WI-38, CHL, CHO, and V79 mammalian cell lines. In vivo studies have been carried out on somatic and/or germ cells of Drosophila melanogaster, rats and mice. Nearly all studies, especially those using validated test systems, indicate that BHT lacks clastogenic potential. In vitro studies on bacterial, yeast and various mammalian cell lines including DON, CHO, CHL cells and primary hepatocytes demonstrate the absence of interactions with or damage to DNA. Taking all the existing data into account, the weight of evidence suggests that BHT does not represent a relevant mutagenic/genotoxic risk to man.     

The effects of natural variation in background radioactivity on humans,animals and other organisms

Natural levels of radioactivity on the Earth vary by more than a thousand‐fold; this spatial heterogeneity may suffice to create heterogeneous effects on physiology, mutation and selection. We review the literature on the relationship between variation in natural levels of radioactivity and evolution. First, we consider the effects of natural levels of radiation on mutations, DNA repair and genetics. A total of 46 studies with 373 effect size estimates revealed a small, but highly significant mean effect that was independent of adjustment for publication bias. Second, we found different mean effect sizes when studies were based on broad categories like physiology, immunology and disease frequency; mean weighted effect sizes were larger for studies of plants than animals, and larger in studies conducted in areas with higher levels of radiation. Third, these negative effects of radiation on mutations, immunology and life history are inconsistent with a general role of hormetic positive effects of radiation on living organisms. Fourth, we reviewed studies of radiation resistance among taxa. These studies suggest that current levels of natural radioactivity may affect mutational input and thereby the genetic constitution and composition of natural populations. Susceptibility to radiation varied among taxa, and several studies provided evidence of differences in susceptibility among populations or strains. Crucially, however, these studies are few and scattered, suggesting that a concerted effort to address this lack of research should be made.     

Studying the impact of the Eurozone’s Great Recession on health: Methodological choices and challenges

Europe’s Great Recession provides an opportunity to study the impact of increased financial insecurity on health. A number of studies explored the impact of the Recession on health, but they often reached different conclusions. To understand the root of this debate, we undertook a systematic literature review. Articles were analysed thematically based on: geography, data type, operationalisations of wealth and health, and study design. A critical appraisal was also undertaken. Forty-two studies, published from January 2010 to October 2018, were included in our review. Twenty-six of the forty-two studies found that the Great Recession worsened physical health indicators in the Eurozone. In terms of geography, a large concentration of studies focussed on Spain and Greece, indicating that there may be a gap in understanding the health consequences for EU countries with less severe experiences of the Recession. Regarding data type, nearly all studies used secondary datasets, possibly meaning that studies were constrained by the data available. In terms of operationalisations of wealth and health, a majority of studies used single/simple measures of both, so that these multi-faceted concepts were not fully reflected. Further, fewer than half included studies used panel data, with the remaining studies unable to undertake more causal analyses. The results of the critical appraisal showed that lower-quality studies tended to not find a negative impact of the Recession on health, whereas higher quality studies generally did. In future, we recommend conducting cross-country comparisons, using (inter)nationally-representative panel data conducted over a minimum of a ten-year time horizon, and employing multi-faceted operationalisations of wealth and health. This could provide more common ground across studies, and a clearer indication of whether the Recession impacted health.     

湿地植物的丛枝菌根（AM）

随着对湿地重要性认识的增加,湿地植物的丛枝菌根（arbuscular mycorrhiza,AM）结构研究受到了关注。研究表明,AM结构在多种湿地类型和湿地植被类型中存在,但AM形成受植被生长地水文状况的影响;从湿地植物上的AM真菌种类看,球囊霉属（Glomus）是湿地环境的常有属。同陆生植物相比,有关湿地植物AM结构的研究尽管已取得了一些进展,但还有很大差距,尤其在我国还几乎处于空白状态。鉴此,从形成AM的湿地植被类型、湿地环境中的AM真菌种类、AM对湿地植物生长的影响,以及影响湿地植物AM形成的因素等方面进行了详细阐述,并对今后的研究方向做了展望,以期为我国开展湿地植物AM结构研究提供参考。     

Evolutionary ecology of intraspecific brain size variation: a review

The brain is a trait of central importance for organismal performance and fitness. To date, evolutionary studies of brain size variation have mainly utilized comparative methods applied at the level of species or higher taxa. However, these studies suffer from the difficulty of separating causality from correlation. In the other extreme, studies of brain plasticity have focused mainly on within‐population patterns. Between these extremes lie interpopulational studies, focusing on brain size variation among populations of the same species that occupy different habitats or selective regimes. These studies form a rapidly growing field of investigations which can help us to understand brain evolution by providing a test bed for ideas born out of interspecific studies, as well as aid in uncovering the relative importance of genetic and environmental factors shaping variation in brain size and architecture. Aside from providing the first in depth review of published intraspecific studies of brain size variation, we discuss the prospects embedded with interpopulational studies of brain size variation. In particular, the following topics are identified as deserving further attention: (i) studies focusing on disentangling the contributions of genes, environment, and their interactions on brain variation within and among populations, (ii) studies applying quantitative genetic tools to evaluate the relative importance of genetic and environmental factors on brain features at different ontogenetic stages, (iii) apart from utilizing simple gross estimates of brain size, future studies could benefit from use of neuroanatomical, neurohistological, and/or molecular methods in characterizing variation in brain size and architecture.     

中国植物化石角质层研究综述

总结近30年来中国大陆植物化石角质层研究的进展,介绍角质层分析的3个主要研究方向:植物化石表皮微细构造研究、植物化石气孔参数与大气CO2和气候变化研究以及植物化石角质层地球化学特征研究.举出众多典型实例,提出植物化石角质层分析的研究展望.     

穿山甲生态学研究概况

综述了全球现存7种穿山甲生态学研究概况,目前的研究主要是通过访问法对中国穿山甲(Manis pentadactyla)的栖息地、活动习性、食性、繁殖习性、打洞习性进行一般性的描述。开普穿山甲(M．temminckii)主要集中在家域、活动和运动、食谱和觅食行为生态上,繁殖生态学、种群生态学及栖息地的研究没有涉及。树穿山甲(M．tricuspts)仅见其家域研究的报道。其它4种穿山甲生态学研究未见任何报道。7种穿山甲的习性相似。今后应当强调从生命的各个层次对其生态学进行比较研究,以揭示其存在的生态差异。重点应是洞穴生态、觅食生态、行为生态(如家域与活动)、繁殖生态和种群生态。