水稻苗期耐Cd胁迫的QTL定位分析

[目的]进行水稻苗期耐Cd胁迫的QTL初步定位。[方法]（1）以Lemont（美国）和Dular（印度）杂交建立的重组自交系（RILs）群体,包括123个家系和亲本在内,用含有0.2mg/L镉的水培液进行处理,以不加镉培养的水培液作为对照,考察了叶绿素含量、根长、株高、叶长等4个性状,并转换成抗性指数,用于评价水稻对Cd污染的抗性指标。（2）在已构建的以109个引物为基础的遗传图谱上进行复合区间定位。[结果]（1）共检测到9个加性QTLs,涉及1,2,3,11等4条染色体,其中,以叶绿素抗性指数为指标,检测到3个与耐Cd有关的QTLs 分别位于第2,3,11染色体上,解释了14%,9%,9%的表型变异;（2）以根长抗性指数为评价指标,只定到1个位于第1染色体上控制耐Cd的QTLs,解释了9%的表型变异; （3）用株高抗性指数进行定位,共有3个与耐Cd相关的QTLs,位于1,1,11染色体上,分别解释了10%,27%,10%的表型变异;（4）而以叶长抗性指数进行水稻秧苗耐Cd性表现的QTL定位,结果发现也有2个QTLs与其耐Cd 反应有关,它们分别位于1,11染色体上,解释了21%,12%的表型变异。分析表明,在采用不同评价指标所检测到的9个与耐Cd相关的QTLs中,有7个集中于第1和第11染色体上,其中第1染色体上有4个,第11染色体上有3个。（结论）以株高和叶绿素抗性指数为评价指标,检测到的QTLs最多,根长抗性指数为评价指标的最少。研究还发现在第1和第11染色体上的相同区间内同时检测到以不同抗性指数为评价指标的多个与耐Cd相关的QTLs,推测它们可能是功能相同的几个紧密连锁的非等位基因,也可能就是同一等位基因的不同表现形式,从而也说明了该评价指标用于基因定位的准确性和可行性。     

QTL alleles from a winter feed type can improve malting quality in barley

Mapping quantitative trait loci (QTLs) responsible for malting quality traits in barley populations has been the main genetic approach to malting quality breeding. A ‘winter × spring’ doubled haploid barley population ‘Nure’ × ‘Tremois’, where such traits were segregating, has been recently developed. Our objective was to map QTLs for malting quality from 2 years of trials in two contrasting locations. QTLs were found on six chromosomes, with a main cluster on chromosome 1H. For wort viscosity and malt extract, favourable alleles at two loci on chromosome 5H were carried by the winter feeding parent ‘Nure’. Doubled‐haploids with higher quality than the spring malting cultivar ‘Tremois’ showed either a facultative or a winter growth habit and a level of frost tolerance comparable with that of the winter tolerant parent ‘Nure’. Markers and QTLs of quality traits were further validated on a separate set of DH lines, coming from the same cross, by means of marker‐assisted selection. This showed that, at least in the present cross combination, positive contributions to malting quality can be found in winter feed barley.     

甘蓝型油菜胚色素成分的QTL定位

以甘蓝型黄籽油菜GH06和甘蓝型黑籽油菜中油821为亲本杂交,后代通过“一粒传法”连续自交7代构建重组自交系, 2007年分别在重庆市北碚区和万州区两个试验基地种植重组自交系群体, 利用本实验室已构建的遗传连锁图谱和复合区间作图法(CIM), 分析种胚色素的4种主要成分的QTL。结果共检测到31个QTL, 分别位于14个不同的连锁群, 其中5个花色素含量有QTL, 分别位于第1、5、10、16和20连锁群,单个QTL解释表型变异的6.08%~11.67%;10个类黄酮含量有QTL, 分别位于第1、3、6、7、12、20和25连锁群,单个QTL解释表型变异的4.48%~11.10%;8个总酚含量有QTL, 分别位于第1、2、12、16和20连锁群,单个QTL解释表型变异的5.24%~10.37%;8个黑色素含量检测到QTL, 分别位于第5、8、10、12、14和22连锁群,单个QTL解释表型变异的5.44%~11.32%。解释表型变异大于10%的5个QTL, 包括2个类黄酮含量QTL, 花色素含量、总酚含量和黑色素含量QTL各1个,它们分别解释11.10%、10.20%、11.67%、10.37%和11.32%的表型变异。研究结果表明胚色素表现为多基因控制的数量性状, 基因表达受环境影响较大, 胚与种皮色素的QTL吻合度不高, 推测种皮和胚色素合成可能受不同遗传体系控制, 与这些QTL紧密相关的分子标记可以用于胚主要色素的分子标记辅助选择。     

关于国际森林问题的思考

介绍了国际森林问题的由来、内涵和特点, 分析了发展中国家和发达国家在全球森林可持续经营中面临的问题、成因和对实质性根源等方面的共识, 提出我国参与国际森林问题谈判应当遵循的原则。     

Mapping adaptation of barley to droughted environments

Identifying barley genomic regions influencing the response of yield and its components to water deficits will aid in our understanding of the genetics of drought tolerance and the development of more drought tolerant cultivars. We assembled a population of 192 genotypes that represented landraces, old, and contemporary cultivars sampling key regions around the Mediterranean basin and the rest of Europe. The population was genotyped with a stratified set of 50 genomic and EST derived molecular markers, 49 of which were Simple Sequence Repeats (SSRs), which revealed an underlying population sub-structure that corresponded closely to the geographic regions in which the genotypes were grown. A more dense whole genome scan was generated by using Diversity Array Technology (DArT®) to generate 1130 biallelic markers for the population. The population was grown at two contrasting sites in each of seven Mediterranean countries for harvest 2004 and 2005 and grain yield data collected. Mean yield levels ranged from 0.3 to 6.2 t/ha, with highly significant genetic variation in low-yielding environments. Associations of yield with barley genomic regions were then detected by combining the DArT marker data with the yield data in mixed model analyses for the individual trials, followed by multiple regression of yield on markers to identify a multi-locus subset of significant markers/QTLs. QTLs exhibiting a pre-defined consistency across environments were detected in bins 4, 6, 6 and 7 on barley chromosomes 3H, 4H, 5H and 7H respectively.     

网络舆论监督研究综述

随着网络社区、微博、微信等平台的快速发展,信息越来越透明,网络舆论对政府行为形成了较大约束,而在公共决策中,政府对普通民众的声音也越来越重视。因此,利用文献计量方法对2005—2016年CNKI数据库中有关网络舆论监督的有关文献进行梳理,通过对关键词、高产作者、来源期刊和研究机构的分析并运用可视化图谱的方式可以展现该领域研究的影响力、研究热点和发展历程。     

Genetic analysis and validation of quantitative trait loci associated with reproductive-growth traits and grain yield under drought stress in a doubled haploid line population of rice (Oryza sativa L.)

Drought is a major constraint for rice production and yield stability in rainfed ecosystems, especially when it occurs during the reproductive stage. Combined genetic and physiological analysis of reproductive-growth traits and their effects on yield and yield components under drought stress is important for dissecting the biological bases of drought resistance and for rice yield improvement in water-limited environments. A subset of a doubled haploid (DH) line population of CT9993-5-10-1-M/IR62266-42-6-2 was evaluated for variation in plant water status, phenology, reproductive-growth traits, yield and yield components under reproductive-stage drought stress and irrigated (non-stress) conditions in the field. Since this DH line population was previously used in extensive quantitative trait loci (QTLs) mapping of various drought resistance component traits, we aimed at identifying QTLs for specific reproductive-growth and yield traits and also to validate the consensus QTLs identified earlier in these DH lines using meta-analysis. DH lines showed significant variation for plant water status, reproductive-growth traits, yield and yield components under drought stress. Total dry matter, number of panicles per plant, harvest index, panicle harvest index, panicle fertility, pollen fertility, spikelet fertility and hundred grain weight had significant positive correlations with grain yield under drought stress. A total of 46 QTLs were identified for the various traits under stress and non-stress conditions with phenotypic effect ranging from 9.5 to 35.6% in this study. QTLs for panicle exsertion, peduncle length and pollen fertility, identified for the first time in this study, could be useful in marker-assisted breeding (MAB) for drought resistance in rice. A total of 97 QTLs linked to plant growth, phenology, reproductive-growth traits, yield and its components under non-stress and drought stress, identified in this study as well as from earlier published information, were subjected to meta-analysis. Meta-analysis identified 23 MQTLs linked to plant phenology and production traits under stress conditions. Among them, four MQTLs viz., 1.3 for plant height, 3.1 for days to flowering, 8.1 for days to flowering or delay in flowering and 9.1 for days to flowering are true QTLs. Consensus QTLs for reproductive-growth traits and grain yield under drought stress have been identified on chromosomes 1 and 9 using meta-QTL analysis in these DH lines. These MQTLs associated with reproductive-growth, grain yield and its component traits under drought stress could be useful targets for drought resistance improvement in rice through MAB and/or map-based positional analysis of candidate genes.     

猪抗病和免疫相关候选基因的研究进展

通过育种选择提高猪的抗病性,不仅可以为我们提供品质更优良的肉产品;还可以最大限度地减小因疫病给养猪业带来的经济损失。尤其是近年来,随着病害造成的危害和损失越来越严重,抗病育种研究成为各国育种学家倍加关注的焦点。猪的基因组计划和遗传连锁图谱的发展以及DNA分子标记密度的增加,使许多控制猪经济(数量)性状的QTL逐渐被发现,并显示出巨大的应用前景。本文概述了猪抗病性或免疫相关候选基因的研究进展,综述了动物抗病育种研究的现状、存在问题与前景。     

棉花重要数量性状基因定位研究进展

棉花是重要的经济作物,是天然纤维的主要来源之一,也是优质蛋白和食用油的潜在资源。通过各种分子标记技术和数量性状基因(quantitative trait loci, QTL)的定位方法将控制棉花数量性状的基因定位到相应的遗传连锁图谱或染色体上,为研究棉花诸多QTL的图位克隆、抗性机制的遗传揭示、分子标记辅助选择(molecular marker-assisted selection, MAS)、有利基因的定向转移及基因聚合育种等奠定了坚实的基础。综述了近年来棉花重要QTLs定位研究的最新进展,并对研究中存在的主要问题进行了分析和展望。     

Designation and management of large‐scale MPAs drawing on the experiences of CCAMLR

With the adoption of the United Nations Law of the Sea came the need for effective worldwide control of marine fisheries. Initially centred on single species, the tasks have extended to ecosystem‐based management through the concept of marine‐protected areas into habitats and biodiversity. These diverse requirements have placed enhanced responsibilities on fisheries management organizations. Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR) has successfully developed effective management measures for the Southern Ocean but has encountered difficulties in establishing marine‐protected areas. Key to the success of CCAMLR has been the establishment of conservation measures on clearly defined topics through decision making by consensus. It is argued that the problems that CCAMLR has encountered in establishing marine‐protected areas centre on the range of features, in terms of stakeholder interests, to be afforded protection allied to problems with the consensus process. In this paper, the approaches of CCAMLR in converting the conceptual framework of treaty language into practical management measures using consensus are discussed in relation to the manner in which marine‐protected areas might be established within other fisheries management organizations. It is concluded that the most effective approach is as a composite of strictly focussed conservation measures the sum of which cover all facets of a marine‐protected area. This approach has the further advantage that individual components can be changed without opening the whole legal instrument to re‐negotiation.