共查询到18条相似文献，搜索用时 218 毫秒
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【研究目的】为创新玉米育种新材料。【方法】选用热带种质按照不同比例导入到温带种质中,构建梯度热带种质群体,以梯度热带种质群体为试验材料,探讨群体遗传潜力及性状遗传差异。【结果】研究表明,株高(PH)和穗位高(EH)群体间遗传差异极显著,梯度群体的株高和穗位高从100%热带种质群体到50%的热带种质群体呈现出逐渐增高的趋势,但变化幅度不大,当热带种质比例降到25%和12.5%时,株高和穗位高显著降低。【结论】导入12.5%或25%热带种质能产生较广泛变异,符合育种需要。 相似文献
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导入热带种质的温带玉米自交系的利用潜力 总被引：3，自引：0，他引：3
用5个热带及亚热带玉米自交系和5个导入热带种质并经连续回交改良的温带玉米自交系, 采用Griffing双列杂交方法III杂交, 共配制90个杂交组合。2008年、2009年以大面积推广杂交种云瑞6号为对照, 对供试自交系进行配合力、杂种优势及利用潜力研究。结果表明, 导入热带种质并经连续回交改良的温带玉米自交系YML598、YML58的多数性状一般配合力效应为极显著正值, 在杂交育种中具有较大的利用潜力;单株产量配合力效应值与诸多产量影响因素的配合力效应值密切相关, 雌雄间隔期、秃尖与单株产量呈负相关, 而其他性状与单株产量呈正相关;产量对照优势H≥10%的组合大多为热带、亚热带种质×改良温带种质, 单株产量特殊配合力效应为极显著正值的组合均为热带、亚热带种质×改良温带种质, 说明热带、亚热带玉米种质与经热带种质改良后的温带玉米种质之间仍具有较强的杂种优势, 且导入热带种质的温带系与热带、亚热带供体系的杂种优势仍然存在, 其所属的杂种优势群并未改变。以热带、亚热带玉米种质为供体, 采用连续回交的方法改良温带玉米自交系是利用热带、亚热带玉米种质的有效方法。 相似文献
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利用适当的温带种质对外引种质进行改良,可进一步丰富温带玉米遗传基础。以来自CI-MMYT的Pob101群体和我国主要种质的代表系为试验材料,研究不同温带种质比例的Pob101×掖478半外来群体选系与旅大红骨群和Lancaster群的杂种优势,为这些半外来群体的进一步改良和利用提供依据。结果表明,理论上含有75%温带血缘的Pob101×掖478半外来群体选系与旅大红骨群和Lancaster群的杂种优势均值均大于含有25%温带血缘的掖478×Pob101半外来群体选系与旅大红骨群和Lancaster群的杂种优势均值,在高产育种中有较大的利用潜力。 相似文献
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以36份芒果种质为试材,利用高效液相色谱技术,进行芒果果实含糖量（果糖、葡萄糖和蔗糖）的分析测定。结果表明,不同芒果种质间含糖量差异较大,Dashehari糖含量最高,达16.04%,‘林生芒’最低,仅为3.49%。不同种质这3种糖的比例有较大差异,根据单糖、双糖的比例,将芒果种质分为3个类型：蔗糖积累型,如‘海豹’、Lippens、‘金煌’、‘四季芒’等;己糖积累型如KRS、‘林生芒’和20001;中间类型如‘桂香’、‘黄象牙’、‘斯里兰卡811’、‘泰国504’、‘乳芒’、紫花。同时根据芒果果实含糖量,对36份芒果种质采用平均距离法进行聚类分析,第1类芒果种质包括：R2E2、‘海豹’、Bambaroo、‘金煌’、‘黄象牙’、‘乳芒’、‘泰国504’、Keitt、‘紫花’、‘桂香’、‘斯里兰卡811’、KRS共12个品种;第2类芒果种质包括：Ono、‘四季芒’、‘红象牙’、‘实选4’、Lippens、‘台农1号’、Mallika、‘台红’等21个品种;第3类包括Dashehari这个品种,第4类包括20001这个品种;第5类包括林生芒。 相似文献
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几个CIMMYT热带群体与中国温带玉米自交系杂种优势的关系 总被引：2，自引：0，他引：2
采用NCⅡ遗传交配设计,研究了来自CIMMYT的5个热带群体与12个中国温带骨干自交系的杂种优势表现。结果显示,热带群体Pop49（Tuxpeno）、Pop32（ETO）、Popstay-green和PooB4与近年来选自外引种质的P群自交系的平均产量表现较突出,其中群体Pop49与之的平均产量表现最突出;热带群体Suwan-1则与中国温带传统骨干系有着较为突出的平均产量表现。配合力分析表明,P群自交系与群体Suwan-1的sca（特殊配合力）水平较低,中国传统温带骨干系与群体Suwan-1的sea水平均较高。这表明P群自交系与群体Suwan-1则有相近的遗传背景。在温带适应性较好的P群自交系可以作为热带种质Suwan-1快速有效导入温带种质的桥梁;中国传统骨干温带骨干系则与群体Suwan-1的遗传关系较远,Suwan-1热带种质在温带可与传统温带种质构成重要杂种优势模式;群体Popstay-green和Pop49的产量gca（一般配合力）为正值较高,表现出较高的利用潜力。研究结果为更好的利用来自CIMMYT的5个热带群体提供了有用的信息。 相似文献
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种质资源狭窄和杂种优势单一,是制约我国玉米产业发展的重要因素之一。拓宽玉米种质基础,培育突破性育种新材料是选育优良玉米杂交种的基础与前提。热带、亚热带种质已经被证明具有较温带种质丰富的遗传多样性,其引入、改良和应用对丰富我国玉米种质多样性具有十分重要的意义。本研究以28份温热玉米自交系、4份Suwan群体来源自交系(QR 273、ZHL 908、T 32和QB 48)作母本,来自Iodent、Reid、PB、Lancaster和塘四平头类群的8个温带玉米自交系作父本的杂交后代为材料,2015年分别在河南郑州和河南华县对28份自交系和32个杂交组合进行农艺性状评价。结果显示,Suwan×Iodent杂交组合的株型、生育期、感光性等与温带地区杂交种相近;而Suwan自交系与其他类群自交系的杂交组合则表现出植株繁茂、抗倒性差、感光性强和生育期太晚等问题。利用Iodent种质早熟、马齿的特性能够有效改良Suwan种质生育期晚、光周期敏感的不足,获得较高的配合力。 相似文献
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热带、亚热带玉米杂交种项目十分重视优良杂交种种质材料的选育，育过程中特别强调种质的耐自交能力，用SD轮回选择法改良耐自交能力是可行的，自交系的选育常用穗行选或系谱法，近几自交系测验种的使用明显增加。世界上广泛利用的热带、亚热带玉米杂种优势群有Tuxpeno,Cubanflints,Coastaltropical flints,ETO和Tuson,把带来、亚热带玉米种质引入温带，可以拓宽温带种质的遗传基础，提高杂种优势潜力，云南省农科院已成功改良了一部分热带、亚热带玉米种质，并在生产中利用。 相似文献
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武夷岩茶“十大名丛”种质生物学特性的鉴定与评价 总被引：1，自引：1，他引：0
为了进一步对武夷岩茶名丛种质进行筛选和鉴定,对在武夷山收集、保存的“十大名丛”种质,严格按照茶树种质资源的调查统计方法进行科学严谨的调查、观测,记录其植株特性、新梢特性、叶片形态和花果特性等生物学特性,进行比较分析。结果表明：“十大名丛”种质综合性状表现优良,各名丛间生物学特性的不同方面各有差异,无特性完全相同的名丛;‘铁罗汉’、‘北斗’、‘白瑞香’及‘金锁匙’春茶开采期较早,‘大红袍’、‘水金龟’、‘白鸡冠’、‘半天妖’、‘金桂’及‘白牡丹’春茶开采期较晚;此外,试验中发现个别性状如芽叶色泽、芽叶茸毛、叶齿、叶尖、叶缘、花冠直径、花瓣数等有不同程度差异。武夷岩茶“十大名丛”种质生物学特性的鉴定与评价,将为武夷岩茶优良种质的推广应用提供理论依据。 相似文献
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Adaptation of tropical maize germplasm to temperate environments 总被引：1，自引：0，他引：1
Maize (Zea mays L.) is one of few crops that can offer significant genetic gains with the utilization of genetic diversity. Genetically broad-based germplasm has the potential to contribute useful and unique alleles to U.S. Corn Belt breeding programs not present in current U.S. genome sequences (e.g. B73, NAM, etc.). Our objectives were to determine if unique tropical genetic materials have been effectively adapted to temperate environments and how their agronomic performance was relative to adapted populations. An important long-term objective of the Iowa and North Dakota maize breeding programs has been, in addition to the typical elite by elite line pedigree selection cultivar development process, to adapt exotic and unique germplasm, maximize their genetic improvement, and develop unique products for breeding and commercial uses. Stratified mass selection methodology for earliness has been utilized for the adaptation of tropical and temperate populations to Iowa and North Dakota environments. This method has allowed screening of up to 25,000 genotypes per population cycle at a rate of one cycle per year. In addition, the estimated cost per year our programs had for the adaptation of each population was less than $2,000 which could successfully be applied in any breeding program across the globe. This cost has been less than 1 % of the total cost for finding minor genes on the same trait. Our results showed the successful adaptation of exotic populations was independent from genetic background. We can speculate there are a few major genes responsible for most of flowering date expression. We encourage the use of technology to target traits according to their genetic complexity. Stratified mass selection at the phenotypic level has been successful. Each of the populations with either 25 of 100 % tropical germplasm are available for anyone who may desire to expand the germplasm base of their breeding programs with tropical germplasm adapted to temperate mid- and short-season U.S. Corn Belt environments. 相似文献
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为评价控制双亲混合选择对1份非洲玉米种质合成基础群体AC0主要性状适应性改良效果,利用联合方差分析和变异系数分析群体间性状变异程度。结果表明,改良群体AC1和AC2的株高分别比AC0提高了8.60%和11.60%,差异达到极显著水平;穗位分别比AC0提高了11.34%和16.18%,差异达到极显著水平;改良群体AC1和AC2的穗长与AC0相比分别降低2.60%和提高1.57%,AC1与AC2间达到极显著水平;与AC0相比,AC1和AC2穗行数分别提高了2.44%和1.12%,均未达到显著水平;与AC0相比,AC1和AC2的秃尖长分别提高了0.75%和13.12%,均未达到显著水平。由以上可知,虽然控制双亲混合选择对热带种质产量性状早期改良进展较小,但随着改良的进行,群体多数性状的表型变异系数有所下降,但也有部分性状变异系数的变化幅度较小或有所增大,但控制双亲混合选择较好地保持了群体的遗传多样性。 相似文献
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旨在分析热带糯质资源在高粱育种中的利用价值及对杂种优势的影响,以商丘市农林科学院自有种质作为研究对象,导入热带糯质资源,选育出稳定的不育系,并对所配组合的农艺性状进行方差及相关性分析。结果表明：‘M17A’所配组合的产量、穗粒重、单穗重等性状与其他组合比较均达到极显著水平,组合8的小区产量最高,为15.17 kg;穗部各性状与产量间的相关系数依次为穗粒重>单穗重>穗长>千粒重>轴长>着壳率>角质率,穗粒重与产量的相关系数为0.957,呈极显著正相关,说明在高粱高产育种中,应重点选择穗大、结实率高的种质;‘M17A’所配组合的淀粉含量与其他组合比较均达极显著水平,说明高粱淀粉含量受遗传基因控制。对于热带种质的利用应选择大穗型,角质率低的材料。 相似文献
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The effect of introgression of temperate germplasm into an elite tropical maize population, EV8443SR, was studied for different
traits. Two temperate lines, FS14 and DEA, were crossed with EV8443SR. The F1 of each cross was backcrossed to EV8443SR to
produce the BC1. F1 and BC1 were subjected to two cycles of random mating. Random sets of S1 families were derived from the
tropical-temperate populations and the tropical parent for evaluation in two tropical locations. Introgression of FS14 and
DEA into EV8443SR significantly increased earliness, and reduced plant height, number of grains per ear, 1000 grains weight
and grain yield. Significant harvest index increases were observed. The effect of introgression on genetic variance of EV8443SR
varied with trait and sometimes with cross and location. The highest expected genetic progress was obtained in a tropical-temperate
population for most of the traits studied. EV8443SR appeared better than, or pratically equal to, the tropical-temperate populations
as a foundation population to improve grain yield and husk cover.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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Jaime Prohens Pietro Gramazio Mariola Plazas Hannes Dempewolf Benjamin Kilian María J. Díez Ana Fita Francisco J. Herraiz Adrián Rodríguez-Burruezo Salvador Soler Sandra Knapp Santiago Vilanova 《Euphytica》2017,213(7):158
The need to boost agricultural production in the coming decades in a climate change scenario requires new approaches for the development of new crop varieties that are more resilient and more efficient in the use of resources. Crop wild relatives (CWRs) are a source of variation for many traits of interest in breeding, in particular tolerance to abiotic and biotic stresses. However, their potential in plant breeding has largely remained unexploited. CWRs can make an effective contribution to broadening the genetic base of crops and to introgressing traits of interest, but their direct use by breeders in breeding programs is usually not feasible due to the presence of undesirable traits in CWRs (linkage drag) and frequent breeding barriers with the crop. Here we call for a new approach, which we tentatively call ‘introgressiomics’, which consists of mass scale development of plant materials and populations with introgressions from CWRs into the genetic background of crops. Introgressiomics is a form of pre-emptive breeding and can be focused, when looking for specific phenotypes, or un-focused, when it is aimed at creating highly diverse introgressed populations. Exploring germplasm collections and identifying adequate species and accessions from different genepools encompassing a high diversity, using different strategies like the creation of germplasm diversity sets, Focused identification of germplasm strategy (FIGS) or gap analysis, is a first step in introgressiomics. Interspecific hybridization and backcrossing is often a major barrier for introgressiomics, but a number of techniques can be used to potentially overcome these and produce introgression populations. The generation of chromosome substitution lines (CSLs), introgression lines (ILs), or multi-parent advanced inter-cross (MAGIC) populations by means of marker-assisted selection allows not only the genetic analysis of traits present in CWRs, but also developing genetically characterized elite materials that can be easily incorporated in breeding programs. Genomic tools, in particular high-throughput molecular markers, facilitate the characterization and development of introgressiomics populations, while new plant breeding techniques (NPBTs) can enhance the introgression and use of genes from CWRs in the genetic background of crops. An efficient use of introgressiomics populations requires moving the materials into breeding pipelines. In this respect public–private partnerships (PPPs) can contribute to an increased use of introgressed materials by breeders. We hope that the introgressiomics approach will contribute to the development of a new generation of cultivars with dramatically improved yield and performance that may allow coping with the environmental changes caused by climate change while at the same time contributing to a more efficient and sustainable agriculture. 相似文献
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重庆市农业科学院近年引进或选育的来自不同地区的甜玉米种质材料,部分种质资源遗传背景较为模糊,对进一步通过杂交方式选育优良品种造成一定障碍。本研究以重庆市农业科学院近年选育或引进的93份来自不同地区的甜玉米种质材料为研究对象,对吐丝期、成熟期、株高、穗位高、总叶片数、穗长、穗粗、轴粗、秃尖长、穗行数、行粒数、单穗粒重、百粒重共13个性状进行统计分析,单因素方差分析表明,各性状均达到了显著水平,说明13个性状均存在真实的差异,变异系数差别最大的是秃尖长,为27.5%,变异系数最小的是生育期和成熟期,为2.4%。对其农艺性状进行相关性分析表明,产量性状与植株性状相关性较高,单穗粒重与吐丝期、株高、穗位高、总叶片数、穗长、行粒数呈显著正相关。通过聚类分析,93份材料可以划分为4个类群,结果较符合已知亲缘关系。93份材料遗传变异丰富,为甜玉米自交系创制、性状改良提供了部分可利用的资源,可为后续甜玉米杂种优势利用及新组合测配提供参考。 相似文献
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Wild relatives and un-adapted germplasm of crop species harbors several adaptive traits.Introgression of genes for economic and adaptive traits brings in novel genetic variation into the gene pools of many crops including cotton.We compared patterns of introgression into polyploid Gossypium hirsuture from its sister G.tomentosum,and from G.barbadense representing a different clade tracing to the same polyploidization.Advanced-generation populations,resulting from recurrent backcrossing to G.hirsutum,show a paucity of G.tomentosum alleles and severe deficiencies of homozygotes. 相似文献
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玉米光周期敏感相关性状发育动态QTL定位 总被引：2，自引：1，他引：1
玉米是短日照作物,大多数热带种质对光周期非常敏感。光周期敏感性限制了温、热地区间的种质交流。研究玉米光周期敏感性的分子机理,有利于玉米种质的扩增、改良、创新,提高玉米品种对不同光周期变化的适应性。本研究以对光周期钝感的温带自交系黄早四和对光周期敏感的热带自交系CML288为亲本配置的组合衍生的一套207个重组自交系为材料,在长日照环境条件下对不同发育时期的叶片数、株(苗)高变化进行QTL分析。结果表明,双亲间的最终可见叶片数和株高差异很大;发育初期CML288的叶片数和苗高都低于黄早四,而发育后期CML288的叶片数和株高都明显高于黄早四;测定各时期F7重组自交系间也存在显著差异。利用包含237个SSR标记、图谱总长度1 753.6 cM、平均图距7.40 cM的遗传连锁图谱,采用复合区间作图法,分别检测到控制叶片数和株(苗)高发育的QTL 11个和20个。但是,没有一个条件QTL 能在测定的几个时期都有效应。在长日照条件下,控制叶片数与株(苗)高的非条件与条件QTL主要集中在第1、9和10染色体上,特别是在第10染色体的标记umc1873附近均检测到了影响这两个性状的QTL,且在不同的发育时期单个条件和非条件QTL所解释的表型变异分别为4.34%~25.74%和10.02%~22.57%,表明这一区域可能包含光周期敏感性关键基因。 相似文献