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Sexual selection is a potent evolutionary force. However, very few models have considered the evolution of female preferences for traits expressed in both sexes. Here we explore how female preferences coevolve with sexually antagonistic traits, which involve alleles that are beneficial to one sex but harmful to the other. We show that with a sexually antagonistic trait on the X chromosome (males XY, females XX), females evolve to prefer mates carrying alleles beneficial to daughters. In contrast, with a Z-linked trait (males ZZ, females ZW), females more often evolve mating preferences for mates carrying alleles beneficial to sons (that is, flashy displays). 相似文献
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Sexual conflict is thought to be a potent force driving the evolution of sexually dimorphic traits. In the water strider Rheumatobates rileyi, we show that elaborated traits on male antennae function to grasp resistant females during premating struggles. Using RNA interference, we uncovered novel roles of the gene distal-less (dll) in generating these male-specific traits. Furthermore, graded reduction of the grasping traits resulted in a graded reduction of mating success in males, thus demonstrating both selection for elaboration of the traits and the role of dll in their evolution. By establishing developmental genetic tools in model systems where sexual selection and conflict are understood, we can begin to reveal how selection can exploit ancient developmental genes to enable the evolution of sexually dimorphic traits. 相似文献
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Theory on the evolution of ornamental male traits by sexual selection assumes consistency in selection over time. Temporal variation in female choice could dampen sexual selection, but scant information exists on the degree to which individual female preferences are flexible. Here we show that in lark buntings sexual selection on male traits varied dramatically across years and, in some cases, exhibited reversals in the direction of selection for a single trait. We show that these shifts are probably because of flexibility in mate choice by individual females and that they parallel shifts in the male traits that predict female reproductive success in a given year. Plasticity in choice and concomitant reversals in mating patterns across time may weaken the strength of sexual selection and could maintain genetic variation underlying multiple sexual ornaments. 相似文献
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【目的】分析国内外236份黄瓜种质资源的遗传多样性,筛选优质种质,为黄瓜新品种选育提供优良亲本材料,也为优良基因挖掘及种质资源利用、保护提供参考。【方法】以来自云南省内、省外及国外的236份黄瓜种质为试料,对其12个性状(2个质量性状和10个数量性状)进行测定,通过遗传变异分析、相关性分析、主成分分析和聚类分析对这些种质进行遗传多样性分析及综合评价,筛选出优质种质。【结果】236份黄瓜种质变异系数最大的是雌花节率,为145.46%,变异系数最小为叶形指数,为4.68%,数量性状变异系数高于质量性状;平均遗传多样性指数为1.633,以子叶宽最高,为2.092,以叶色最低,为0.389。雌花节率与叶色呈显著正相关(P< 0.05,下同),与子叶长、子叶宽、结瓜习性、成株叶长和叶形指数呈极显著正相关(P< 0.01,下同),与第一雌花出现节位、雄花节率、节间长和主蔓长呈极显著负相关;第一雌花出现节位与雄花节率和结瓜习性呈极显著正相关,与叶形指数呈显著负相关,与雌花节率和子叶宽呈极显著负相关。主成分分析结果显示,前5个主成分因子累计贡献率达80.823%,第一因子是雌花节率主分量,第二因子是成株叶宽主分量,第三因子是第一雌花出现节位主分量,第四因子是子叶长主分量,第五因子是叶色主分量。236份黄瓜种质材料分成八大类群(Ⅰ~Ⅷ),其中第Ⅵ类群和Ⅶ类群的生长势强,雄花占比多,在育种中可作为父本材料,第Ⅷ类群的雌花占比多,单性结实率高,在育种中可作为母本材料。【结论】236份黄瓜种质具有丰富的遗传多样性,选择育种潜力巨大。在黄瓜育种时,可将叶面积、叶色、第一雌花出现节位、结瓜习性和雌花节率等性状作为产量性状进行改良,且选育早熟高产品种时应注重第一雌花出现节位、雄花节率和结瓜习性等性状。 相似文献
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本文以9个芝麻品种(系)为试验材料,估算了10个性状的遗传力、遗传变异系数、遗传进度和基因型相关。结果表明:不同性状间的遗传力、遗传变异系数和遗传进度,存在较大差异,产量性状的遗传力较经济性状的遗传力大,性状间存在正相关和负相关,千粒重和每蒴粒数的遗传力高,可在早世代选择;株高和分枝部位的遗传力低,可在高世代定向连续选择或间接选择;单株蒴果数和单株产量的遗传变异系数和遗传进度大,可根据表现型选择;株高分枝数和千粒重遗传变异数和遗传进度小,根据表现型选择效果较差,可适当放宽选择标准,使单株果数、每蒴粒数、千粒重与单株产量的相关都达到显著水平高,但3者之间存在不同程度的负相关。故对这类性状、应采用选择指数分析法进行多性状的综合选择。 相似文献
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新铁炮百合自交后代主要性状遗传变异的初步研究 总被引:6,自引:1,他引:6
对新铁炮百合自交后代主要性状的遗传变异进行了初步研究。结果表明,所研究的大部分性状在株系间具有较大的变异,花头数、子房长、株高、茎粗、上部叶长、上部叶长/宽、中部叶长、中部叶长/宽、下部叶长、下部叶长/宽等性状的遗传力、遗传进度均表现较高且遗传变异系数大,早代严格选择效果明显;而内花被第、内花被宽/长、外花被宽/长等性状或遗传力较小,或遗传变异系数较小,甚至两者都小,选择时可放宽尺度;叶密度等性状易受环境的影响,应严格控制试验条件,自交后代不同株系不同性状的稳定速度不同。 相似文献
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向日葵主要农艺性状的遗传分析 总被引:1,自引:0,他引:1
本试验对20个向日葵品种的主要农艺性状进行了遗传分析。结果表明:出苗──现蕾日数,现蕾──开花日数,开花──成熟日数,叶片数、子仁率等农艺性状都有较大的遗传力。可以在早代单株选择或直接选择。而单株粒重、小区产量等遗传力较低的农艺性状应根据性状间相关关系进行间接选择或多环境选择。某性状的遗传改良效果由该性状的遗传力和变异幅度共同决定。 相似文献
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Bernasconi G Ashman TL Birkhead TR Bishop JD Grossniklaus U Kubli E Marshall DL Schmid B Skogsmyr I Snook RR Taylor D Till-Bottraud I Ward PI Zeh DW Hellriegel B 《Science (New York, N.Y.)》2004,303(5660):971-975
The life cycles of sexually reproducing animals and flowering plants begin with male and female gametes and their fusion to form a zygote. Selection at this earliest stage is crucial for offspring quality and raises similar evolutionary issues, yet zoology and botany use dissimilar approaches. There are striking parallels in the role of prezygotic competition for sexual selection on males, cryptic female choice, sexual conflict, and against selfish genetic elements and genetic incompatibility. In both groups, understanding the evolution of sex-specific and reproductive traits will require an appreciation of the effects of prezygotic competition on fitness. 相似文献
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数量性状遗传基础研究的回顾与思考--后基因组时代数量遗传领域的挑战 总被引:15,自引:4,他引:15
莫惠栋 《扬州大学学报(农业与生命科学版)》2003,24(2):24-31
回顾了100多年来数量性状遗传研究的发展。数量性状的遗传研究长期落后于质量性状的研究,主要是对其遗传基础缺乏必要的了解。20世纪80年代开始,DNA分子标记的大量开发,提供了遍布于基因组的位置参照点,促进了数量性状遗传基础研究的迅速发展。迄今至少已对68个生物种的很多数量性状(包括动、植物的重要经济性状和人类疾病)作过全基因组的数量性状座位(QTL)扫描,建立了QTL图谱。但是一般地说,QTL仍然是一个相当大的DNA片断,往往含有多个基因。遗传基础的进一步研究应当从QTL到数量性状基因(QTG),再从QTG到相应于等位基因的数量性状核苷酸(QTN),逐步深入下去。这是后基因组时代数量遗传领域的主要挑战。基因组上数以万计的DNA序列变异(例如SNP)以及模式生物全基因组测序的完成,已为这种准确的遗传剖分提供了必要的条件。 相似文献
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Gratten J Wilson AJ McRae AF Beraldi D Visscher PM Pemberton JM Slate J 《Science (New York, N.Y.)》2008,319(5861):318-320
The evolutionary changes that occur over a small number of generations in natural populations often run counter to what is expected on the basis of the heritability of traits and the selective forces acting upon them. In Soay sheep, dark coat color is associated with large size, which is heritable and positively correlated with fitness, yet the frequency of dark sheep has decreased. This unexpected microevolutionary trend is explained by genetic linkage between the causal mutation underlying the color polymorphism and quantitative trait loci with antagonistic effects on size and fitness. As a consequence, homozygous dark sheep are large, but have reduced fitness relative to phenotypically indistinguishable dark heterozygotes and light sheep. This result demonstrates the importance of understanding the genetic basis of fitness variation when making predictions about the microevolutionary consequences of selection. 相似文献
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刺槐家系耐盐性状的变异、相关分析及选择 总被引:13,自引:0,他引:13
①根据对不同盐浓度处理下刺槐家系苗高、地径及它们的绝对和相对生长量的调查分析,得出短期盐胁迫下苗高绝对生长量及其相对生长量能灵敏反映出苗木受盐害的程度,其它指标用于评价苗期耐盐性的效果较差.②根据对盐胁迫下40个刺槐家系各生长性状的调查分析,研究了它们的遗传变异,并用指数选择法对刺槐家系进行了选择.结果表明:刺槐家系的各耐盐性状受较大程度的遗传控制,环境效应影响较小,通过选择可望取得明显遗传进展;指数选择在刺槐家系多性状综合选择时有较好效果,对各约束性状的控制也可达到预期目的.③根据对盐胁迫下6个刺槐家系盆栽苗的苗高、苗高绝对生长量、苗高相对生长量、水势、电导率和叶部钾钠比的调查分析,研究了它们的遗传变异、各性状间的相关关系和它们对苗高的通径分析.结果表明:苗高和苗高绝对生长量之间相关性非常紧密(r=0.700),与苗高相对生长量之间相关性一般(r=0.451),苗高绝对生长量与苗高相对生长量遗传相关略高(r=0.635),苗木水势和质外体电导率与苗高的表型和遗传相关均表现适度的负相关;苗高生长主要受苗高绝对生长量的直接效应的影响,直接通径系数次序为苗高绝对生长量、钾钠比、水势、电导率和苗高相对生长量,苗高相对生长量、钾钠比、水势和电导率通过对苗高绝对生长量间接效应来影响苗高的生长. 相似文献
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Constraint to adaptive evolution in response to global warming 总被引:1,自引:0,他引:1
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. 相似文献
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研究表明,甘薯集团杂交后代30个实生品系主要数量性状的遗传变异系数均较大.GCV达20.03%-37.65%,具有较高的育种选择潜力.测定和分析了遗传力及遗传进度与表型选择的关系.通过遗传相关、逐步回归和遗传通径分析,提出了集团杂交品系高产的优良基因型表现是:单株结薯数较多,茎叶生长较好,绿叶重较高,蔓较短,其它性状中等,并以此作为高产育种的选择依据. 相似文献
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鹅掌楸属种间杂种苗期生长性状的亲本配合力分析 总被引:8,自引:0,他引:8
利用鹅掌楸属(Liriodendron)6个亲本植株进行全双列杂交,对1a生子代生长性状进行配合力分析的结果表明,在苗高和地径性状上,亲本的一般配合力效应及母本效应均占较大的方差分量,并在地径性状上达到统计上的极显著程度,而特殊正反交效应及父本效应则可以忽略,说明在苗高和地径性状上均存在明显的加性遗传变异,同时也涉及母体和(或)细胞质遗传现象。在6个亲本植株中,H2和H4在苗高性状和地径性状上都具有较高的一般配合力效应和母本效应,可在今后杂交育种中使用。苗高与地径两性状之间的遗传相关系数(rg)为0.4138,说明两性状在遗传控制上具有一定的相关性,可对两性状同时进行改良,并可进行相关选择。 相似文献
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海岛棉早熟性与产量性状遗传相关分析 总被引:1,自引:1,他引:0
试验对7个亲本采用完全双列杂交设计,配置42个杂交组合.结果表明,F1、F2在出苗、现蕾期和初絮期早熟性状均比中亲值提前,F2表现更早熟,产量及其组分均有一定中亲优势,尤其籽棉产量优势最高;单铃重、衣分、衣指与现蕾期和初絮期均有显著或极显著的正相关,分别为0.809 2、0.518 5和0.699 8,初絮期对霜前皮棉产量影响显著;初絮期、衣分、衣指和单铃重遗传力较高,可对这4个性状进行早代选择.变异系数只有霜前花率、单铃重较高,表明在这些性状中具有较高的选择潜力.在5;遗传进度中,对霜前花率和单株籽棉产量选择效果明显. 相似文献
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Saether SA Saetre GP Borge T Wiley C Svedin N Andersson G Veen T Haavie J Servedio MR Bures S Král M Hjernquist MB Gustafsson L Träff J Qvarnström A 《Science (New York, N.Y.)》2007,318(5847):95-97
Interbreeding between species (hybridization) typically produces unfit offspring. Reduced hybridization should therefore be favored by natural selection. However, this is difficult to accomplish because hybridization also sets the stage for genetic recombination to dissociate species-specific traits from the preferences for them. Here we show that this association is maintained by physical linkage (on the same chromosome) in two hybridizing Ficedula flycatchers. By analyzing the mating patterns of female hybrids and cross-fostered offspring, we demonstrate that species recognition is inherited on the Z chromosome, which is also the known location of species-specific male plumage traits and genes causing low hybrid fitness. Limited recombination on the Z chromosome maintains associations of Z-linked genes despite hybridization, suggesting that the sex chromosomes may be a hotspot for adaptive speciation. 相似文献