Constraint to adaptive evolution in response to global warming

We characterized the genetic architecture of three populations of a native North American prairie plant in field conditions that simulate the warmer and more arid climates predicted by global climate models. Despite genetic variance for traits under selection, among-trait genetic correlations that are antagonistic to the direction of selection limit adaptive evolution within these populations. Predicted rates of evolutionary response are much slower than the predicted rate of climate change.     

A rapid shift in a classic clinal pattern in Drosophila reflecting climate change

Geographical clines in genetic polymorphisms are widely used as evidence of climatic selection and are expected to shift with climate change. We show that the classic latitudinal cline in the alcohol dehydrogenase polymorphism of Drosophila melanogaster has shifted over 20 years in eastern coastal Australia. Southern high-latitude populations now have the genetic constitution of more northerly populations, equivalent to a shift of 4 degrees in latitude. A similar shift was detected for a genetically independent inversion polymorphism, whereas two other linked polymorphisms exhibiting weaker clinal patterns have remained relatively stable. These genetic changes are likely to reflect increasingly warmer and drier conditions and may serve as sensitive biomarkers for climate change.     

Polymorphism of Kunitz Trypsin Inhibitor Protein in Natural Populations of Wild Soybean in Hebei

Hebei Province is one of the main distribution areas growing wild soybean( Glycine soja ) in China. In this study, 461 seed samples,collected from 18 natural populations in this province, were used to electrophoretically observe the change in forms and their frequencies of the Kunitz trypsin inhibitor protein (KTI)in individual populations and geographical areas. Allelic frequencies accounted for 85% for Tia and 15% for Tib in the total samples. Twelve populations examined were polymorphic at the KTI locus, accounting for over 50% in the populations investigated. Four populations, 22% of all the populations, were found to have natural cross-pollination with varied heterozygote rates of 3% -5.5%, and the average was 1% in the total sampies. Geographically, the mean Tib frequency in the north areas was higher than in the south, and higher in the mountainous area than in the plain areas. The populations in a lake ecological environment (Baiyangdian Lake) were almost monomorphic. No obvious relationship between the frequency and the geographical distance was observed. In addition, we first found a mutation for the absence of the KTI in wild soybean.     

The importance of land-cover change in simulating future climates

Adding the effects of changes in land cover to the A2 and B1 transient climate simulations described in the Special Report on Emissions Scenarios (SRES) by the Intergovernmental Panel on Climate Change leads to significantly different regional climates in 2100 as compared with climates resulting from atmospheric SRES forcings alone. Agricultural expansion in the A2 scenario results in significant additional warming over the Amazon and cooling of the upper air column and nearby oceans. These and other influences on the Hadley and monsoon circulations affect extratropical climates. Agricultural expansion in the mid-latitudes produces cooling and decreases in the mean daily temperature range over many areas. The A2 scenario results in more significant change, often of opposite sign, than does the B1 scenario.     

Low potential for climatic stress adaptation in a rainforest Drosophila species

The ability of sensitive rainforest species to evolve in response to climate change is largely unknown. We show that the Australian tropical rainforest fly Drosophila birchii exhibits clinal variation in desiccation resistance, but the most resistant population lacks the ability to evolve further resistance even after intense selection for over 30 generations. Parent-offspring comparisons indicate low heritable variation for this trait but high levels of genetic variation for morphology. D. birchii also exhibits abundant genetic variation at microsatellite loci. The low potential for resistance evolution highlights the importance of assessing evolutionary potential in targeted ecological traits and species from threatened habitats.     

The response of two contrasting limestone grasslands to simulated climate change

Two different UK limestone grasslands were exposed to simulated climate change with the use of nonintrusive techniques to manipulate local climate over 5 years. Resistance to climate change, defined as the ability of a community to maintain its composition and biomass in response to environmental stress, could be explained by reference to the functional composition and successional status of the grasslands. The more fertile, early-successional grassland was much more responsive to climate change. Resistance could not be explained by the particular climates experienced by the two grasslands. Productive, disturbed landscapes created by modern human activity may prove more vulnerable to climate change than older, traditional landscapes.     

A polytene chromosome analysis of the Anopheles gambiae species complex

Field-collected specimens of all known taxa in the Anopheles gambiae complex were analyzed on the basis of chromosome inversions with reference to a standard polytene chromosome map. The phylogenetic relationships among the seven described species in the complex could be inferred from the distribution of fixed inversions. Nonrandom patterns of inversion distribution were observed and, particularly on chromosome arm 2R, provided evidence for genetically distinct populations in A. gambiae, A. arabiensis, and A. melas. In A. gambiae from Mali, stable genetic differentiation was observed even in populations living in the same region, suggesting a process of incipient speciation which is being confirmed by studies with molecular markers. The possible role of chromosome differentiation in speciation of the A. gambiae complex and in the emergence of distinct chromosomal forms within the nominal species is discussed in relation to human malaria.     

基于Y染色体ZFY-10标记多态性探究柴达木黄牛父系支系组成和起源

为从分子水平上揭示柴达木黄牛的父系遗传结构组成、遗传多样性水平及父系遗传背景,通过PCR方法和直接测序技术,以8头大别山牛(瘤牛)公牛为试验对照,对106头柴达木黄牛公牛Y染色体ZFY-10标记进行多态性检测分析。结果表明:1)通过ZFY-10标记上变异位点的联合定型分析,可以准确地检测普通牛Y1和Y2单倍型组及瘤牛Y3单倍型组;2)柴达木黄牛在ZFY-10标记上存在GT核苷酸插入/缺失多态性,依据该标记多态位点确定单倍型组,表明柴达木黄牛包含Y1和Y2两种普通牛单倍型组,所占频率分别为0.217和0.783。在柴达木黄牛品种内,大柴旦、乌兰、格尔木、茫崖和都兰5个群体Y2单倍型组的频率依次为1.000、0.933、0.907、0.650和0.522,而Y1单倍型组频率依次为0、0.067、0.093、0.350和0.478,表明茫崖和都兰2个群体具有较高的Y1单倍型组比例;3)柴达木黄牛总的单倍型多样度为0.343 0±0.045 6。在柴达木黄牛品种内,大柴旦、乌兰、格尔木、茫崖和都兰5个群体的单倍型多样度分别为0、0.133 3、0.172 8、0.478 9和0.521 7,表明都兰和茫崖2个群体相比其他3个群体具有较高的父系遗传多样性。综上所述,Y染色体ZFY-10标记变异位点的联合定型分析可以确定和推断黄牛的父系支系组成和起源;柴达木黄牛含有Y1和Y2两个普通牛父系支系,具有2个普通牛父系起源,父系遗传多样性较低,品种内茫崖和都兰2个群体遗传变异相对丰富。     

From individual dispersal to species ranges: perspectives for a changing world

Dispersal is often risky to the individual, yet the long-term survival of populations depends on having a sufficient number of individuals that move, find each other, and locate suitable breeding habitats. This tension has consequences that rarely meet our conservation or management goals. This is particularly true in changing environments, which makes the study of dispersal urgently topical in a world plagued with habitat loss, climate change, and species introductions. Despite the difficulty of tracking mobile individuals over potentially vast ranges, recent research has revealed a multitude of ways in which dispersal evolution can either constrain, or accelerate, species' responses to environmental changes.     

Widespread parallel evolution in sticklebacks by repeated fixation of Ectodysplasin alleles

Major phenotypic changes evolve in parallel in nature by molecular mechanisms that are largely unknown. Here, we use positional cloning methods to identify the major chromosome locus controlling armor plate patterning in wild threespine sticklebacks. Mapping, sequencing, and transgenic studies show that the Ectodysplasin (EDA) signaling pathway plays a key role in evolutionary change in natural populations and that parallel evolution of stickleback low-plated phenotypes at most freshwater locations around the world has occurred by repeated selection of Eda alleles derived from an ancestral low-plated haplotype that first appeared more than two million years ago. Members of this clade of low-plated alleles are present at low frequencies in marine fish, which suggests that standing genetic variation can provide a molecular basis for rapid, parallel evolution of dramatic phenotypic change in nature.     

Dynamics of Pleistocene population extinctions in Beringian brown bears

The climatic and environmental changes associated with the last glaciation (90,000 to 10,000 years before the present; 90 to 10 ka B.P.) are an important example of the effects of global climate change on biological diversity. These effects were particularly marked in Beringia (northeastern Siberia, northwestern North America, and the exposed Bering Strait) during the late Pleistocene. To investigate the evolutionary impact of these events, we studied genetic change in the brown bear, Ursus arctos, in eastern Beringia over the past 60,000 years using DNA preserved in permafrost remains. A marked degree of genetic structure is observed in populations throughout this period despite local extinctions, reinvasions, and potential interspecies competition with the short-faced bear, Arctodus simus. The major phylogeographic changes occurred 35 to 21 ka B.P., before the glacial maximum, and little change is observed after this time. Late Pleistocene histories of mammalian taxa may be more complex than those that might be inferred from the fossil record or contemporary DNA sequences alone.     

Status and improvements of coupled general circulation models

Coupled general circulation models (CGCMs) integrate our knowledge about atmospheric and oceanic circulation. Different versions of CGCMs are used to provide a better understanding of natural climate variability on interannual and decadal time scales, for extended weather forecasting, and for making seasonal climate scenario projections. They also help to reconstruct past climates, especially abrupt climate change processes. Model intercomparisons, new test data (mainly from satellites), more powerful computers, and parameterizations of atmospheric and oceanic processes have improved CGCM performance to such a degree that the model results are now used by many decision-makers, including governments. They are also fundamental for the detection and attribution of climate change.     

云南保种乳用圭山羊遗传多样性蛋白电泳研究

 采用水平式淀粉胶蛋白电泳技术,对路南保种乳用圭山羊33个个体的46个遗传座位的血液蛋白及同工酶的多态性进行了研究.结果发现AKP,LAP,CES-I,ESD,ME和Pa6个座位具多态性,多态座位的基因AKP⁰,LAP^A,CES-I¹,ME^B,ESD¹和Pa^A的基因频率较高;多态座位百分比P=0.1304,平均杂合度H=0.0501.在Tf座位,出现两种表型AA,AB,但多态性贫乏;LDH谱带中发现一种不同的类型.结果表明,该品种山羊与已检测的其它山羊比较,蛋白多态水平较高,遗传背景较丰富.     

桔小实蝇研究进展

桔小实蝇Bactrocera(Bactrocera)dorsalis(Hendel)是一种世界危险性检疫害虫,寄主范围广,能危害250多种瓜果蔬菜,随着气候变化、种植结构的调整和国际贸易的增加,其危害面积逐渐扩大,给果蔬业带来严重的经济损失.近年来,针对桔小实蝇的研究逐渐深入,从一开始的基本生物学及生态学研究到最近的分子生物学和适生性分析研究,对桔小实蝇研究逐渐过渡到应用研究方面.文章综述了近年来桔小实蝇的分类特征及地位,生物学和生态学,风险性评价及适生性分析,分子生物学,防治及控制对策等方面的研究进展.     

植物染色体重排在作物遗传改良中的应用研究进展

染色体重排是一种可能导致DNA片段丢失、重复、易位和倒位的机制,从而改变基因组结构,为创造新的变异性状提供可能。植物染色体重排事件的准确鉴定有助于更深入地理解植物基因组的结构、功能及它们在植物演化和作物育种中的作用。该文深入探讨了植物染色体重排的基本概念,介绍了植物染色体重排的自然发生和人工诱导的技术方法,阐述了植物染色体重排的细胞生物学、分子遗传学和高通量测序鉴定方法。同时,系统总结了植物染色体重排技术在作物遗传育种中的应用,结合具体实践,着重强调了染色体重排技术在提高农作物的遗传多样性、改良农作物的重要性状、增强农作物的环境适应性等方面极具优越性。然而,目前染色体重排的发生概率较低,技术上仍存在挑战,需要更多精准的工具和策略来实现染色体片段的精准定位和重排。通过全面了解染色体重排及其相关技术,研究人员和育种家可以更好地利用植物基因组,为全球粮食安全和环境可持续发展提供创新解决方案。相关研究不仅为深入认识植物基因组提供新途径,也为未来创新作物育种奠定坚实基础。通过挖掘植物基因组的多样性和可塑性,染色体重排技术有望为培育高产、优质、多抗的农作物新品种提供更多可能性,对解决全球日益严峻的...     

Adaptive phenotypic plasticity in response to climate change in a wild bird population

Rapid climate change has been implicated as a cause of evolution in poorly adapted populations. However, phenotypic plasticity provides the potential for organisms to respond rapidly and effectively to environmental change. Using a 47-year population study of the great tit (Parus major) in the United Kingdom, we show that individual adjustment of behavior in response to the environment has enabled the population to track a rapidly changing environment very closely. Individuals were markedly invariant in their response to environmental variation, suggesting that the current response may be fixed in this population. Phenotypic plasticity can thus play a central role in tracking environmental change; understanding the limits of plasticity is an important goal for future research.     

元江鲤种群遗传多样性

选择12对微卫星标记检测了于2011年采集自元江(红河上游中国江段)5个样点192尾鲤的群体遗传多样性。共检测到201个等位基因,每个位点等位基因2-27个。各群体各位点平均等位基因(N_A)12.25-14.67个,平均有效等位基因(N_E)8.28-9.73个,平均观察杂合度(H_O) 0.7765-0.8037,平均期望杂合度(H_E)0.7761-0.8080,平均多态信息含量(PIC) 0.7534-0.7843。元江鲤种群192个个体各位点N_A、N_E、H_O、H_E、PIC分别为16.50、11.26、0.7927、0.8049、0.7966,种群遗传多样性水平高。元江鲤群体之间遗传分化小,可作为一个种群管理单元进行管理。增殖放流要防止遗传多样性丧失。     

气候变化对黑龙江玉米产量贡献份额研究

应用AEZ模型计算得到的1980—2009年逐年光温生产潜力和气候生产潜力作为气候变化影响因素,结合搜集到的1980—2009年黑龙江玉米生产的经济社会要素,本研究构建了主成分分析模型进行气候变化对玉米单产的贡献分析。结果表明:"气候变化及应对措施"主成分影响占到10%略多,"经济社会"主成分贡献率最大,达到50%以上;"传统投入"主成分贡献率约17%;相比较"经济社会"和"传统投入"主成分而言,"气候变化及应对措施"贡献份额最低。"气候变化及应对措施"1980—2009年的主成分得分呈现不规则波动,没有明显上升或下降趋势,表明气候的实际作用不明显。同时,该主成分得分与黑龙江玉米产量变化没有相关性;与黑龙江玉米产量呈线性相关的是"经济社会"主成分。     

云南植烟区气候聚类分析

[目的]研究云南烟区6个气候要素的聚类。[方法]采用系统聚类分析对云南植烟区12个地州89个植烟县的6个气象要素进行聚类分析,根据各类型的指标特征及气候特点,对云南省主要植烟区的气候进行划分。[结果]云南省主要植烟区的气候可划分为8个类型,分别是以江川(24个县,属北亚热和中亚热气候带)、嵩明(27个县区,属北亚热和中、南、北温气候带)、腾冲(3个县,属北亚热气候带)、弥勒(12个县,属中亚热和南亚热气候带)、邱北(11个县区,属南亚热气候带)、盐津(4个县,属中亚热带湿润气候带)、元江(4个县,属南亚热和北热气候带)、镇雄(3个县,属暖温带和北亚热气候带)为代表。第1～8生态区气候达1级相似的国内外城市分别有3、1、1、0、1、1、0、1个市,达2级相似的分别有12、15、3、13、13、1、5、3个市。8大生态区中,1级相似的城市相似距离在0.28～0.45,相似程度最高,相互引种容易成功;2级相似的城市相似距离在0.51～1.00,相似程度较高,相互引种成功率较高。[结论]该研究为选择适宜不同地区种植的新、引烤烟品种以及优化不同地区烤烟品种布局提供理论依据。     

菜薹-芥蓝单体异附加系n+1配子传递及两个二体异附加系的获得

【目的】研究菜薹-芥蓝单体异附加系n+1配子传递,为其在基因定位和遗传改良上的应用奠定基础。【方法】通过观察和统计各单体异附加系减数分裂后期Ⅱ10/10/11/11分离的PMCs,估算n+1配子的形成频率;通过鉴定回交子代植株的染色体数目,测定各单体异附加系n+1配子的传递率;从单体异附加系的自交子代中筛选二体异附加系。【结果】依据减数分裂后期Ⅱ10/10/11/11分离的PMCs比率估算,各单体异附加系n+1雄配子的形成频率在36.85%—45.15%;基于染色体数目鉴定,各单体异附加系n+1雄配子的传递率在7.14%—14.81%,雌配子在19.70%—36.51%;在一定范围内,n+1配子传递率与n+1配子形成频率、染色体大小、花粉量和花粉生活力没有显著的相关性;从自交子代中获得了两个不同的二体异附加系。【结论】菜薹-芥蓝各单体异附加系的额外染色体通过雌、雄配子均能进行传递,但传递率因不同的附加系而异;从单体异附加系的自交子代中可以分离出遗传性稳定的二体异附加系。