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1.
采用蒙特卡洛模拟结合混合线性模型的方法,直接从基因型值和分子标记水平上研究了水稻核心种质的11个评价参数,排除了环境因素的干扰,对各个评价参数做出了准确的评价。研究表明,极差符合率(CR)可以作为评价核心种质代表性的首选参数。平均Simpson指数(MD)、平均Shannon Weaver多样性指数(MI)和平均多态信息含量(MPIC)是评价核心种质代表性的重要参数。变异系数变化率(VR)可以作为评价核心种质变异程度的重要参考参数。多态位点百分率(p)可以作为判断核心种质取样规模的判定参数。均值差异百分率(MD)可作为判断核心种质是否具有代表性的判定参数。本研究筛选出的核心种质评价参数,适用于不同的种质资源群体,可以用作确定核心种质取样比例的判定依据,进而解决了确定核心种质合理取样比例的问题。  相似文献   

2.
本研究以收集的248份薏苡种质资源为基础,按地理来源将标准化的14表型数据分组,采用最短距离逐步取样法并按一定比例抽样,共获得8个候选核心子集,利用变异系数变化率、均值差异百分率、极差符合率、方差差异百分率、表型保留比例、表型频率方差和Shannon-Wiener指数7个参数进行核心种质代表性检验和评价。结果表明:薏苡初级核心种质库包含67份资源,保留了原始种质27.02%的样品(25%组内取样比例),其变异系数变化率、均值差异百分率、极差符合率、方差差异百分率、表型保留比例、表型频率方差和Shannon-Wiener指数的检验指标分别为110.05%、0、93.03%、10%、96%、0.655和0.881;t测验结果表明,核心种质库14个表型性状均值与原始种质无显著性差异,仅有3个表型的某一性状级别丢失,其余11个表型均保留了原始种质的所有性状级别(RPR=1.0),保留表型性状级别比例为96.49%,且多数表型性状的变异系数和遗传多样性指数均略高于原始种质。其结果说明,获得的核心种质库代表性好,遗传多样性丰富。该结果为后期薏苡种质资源的收集、保护、创新利用奠定了重要基础。  相似文献   

3.
为鉴定评价我国向日葵(Helianthus annuus L.)种质资源在南方地区的表现,筛选构建向日葵核心种质,以422份向日葵种质为材料,在进行2年鉴定观察的基础上,采用描述性统计、相关性分析、主成分分析等方法对11个表型农艺性状进行分析评价。结果表明,原始群体的这些农艺性状具有较大的变异幅度,其变异系数(CV)为3.60%~83.32%,平均变异系数为20.93%,其中分枝株率(0%~62.5%)、单株粒重(9.70~232.35 g)、百粒重(4.60~14.92 g)、叶片数(14.40~48.38个)和株高(103.75~260.00 cm)变异幅度较大;性状间表现出显著的相关性,主成分分析表明,影响性状的4个主要成分解释了总方差的71.72%。采用QGAstation 2.0软件构建了72组核心种质候选群体,并根据均值差异百分数(MD)、方差差异百分率(VD),极差符合率(CR)和变异系数百分率(VR),获得组获得1组包含84份材料的最佳核心种质群体。聚类分析将84份核心资源分为5大类,与原群体相比,所选核心种质均值无显著差异,方差显著提高,能最大限度代表原始油葵种质资源保存和利用。  相似文献   

4.
基于SSR标记构建甜玉米群体的核心种质   总被引:1,自引:0,他引:1  
利用40对SSR引物分别分析56份超甜玉米和88份普甜玉米群体材料,基于非加权算术平均配对法(UPGMA)聚类分析和位点优先取样法,分别筛选出14个超甜玉米核心材料和19个普甜玉米材料作为两个亚群体种质。t测验表明,两个亚核心种质与原始群体的等位变异无显著差异(P0.05),等位变异保留率分别为87.81%和89.13%,有效地保留了原始材料群体的遗传变异。两个亚群核心种质与原始材料群体13个表型性状的均值、标准差、极差、变异系数和Shannon-Weaver多样性指数(H’)的平均符合率都在80%以上,并且均值差异百分率(MD)和方差差异百分率(VD)均小于20%,极差符合率(CR)和变异系数变化率(VR)均大于80%,符合核心种质的质量评价标准。构建的甜玉米核心种质最大程度地保留了原始群体的遗传多样性和表型变异,能够有效地代表原始甜玉米材料群体。  相似文献   

5.
6.
This study presents the development of a core collection capturing the genetic diversity of a collection of 350 tetraploid cultivated potato varieties (Solanum tuberosum L.). The core collection was established by using simple sequence repeats (SSR) data and the M strategy, which aims at maximizing the allelic diversity. A 48-core collection was defined which captured 99.5% of the SSR alleles used to establish it, and 96.9% of the SSR alleles which belonged to an independent set of markers. The defined core collection was further validated by analysing 35 agro-morphological traits. The class coverage value and the estimates of the Shannon-Weaver diversity index indicated a good representation of the phenotypic diversity in the core collection. Furthermore, the core set included accessions having the most desirable status for several agronomic traits. A linkage disequilibrium (LD) analysis, using data obtained with the SolCAP SNP array on the defined core collection, was performed. The population structure analysis showed that the core collection did not present a clear genetic structure. The linkage disequilibrium analysis carried out between markers located on the same pseudomolecule within 10,000 bp concluded that 41.3% of these pairs of SNP markers have a significant LD. We conclude that this core collection, representative of the genetic diversity of cultivated potato varieties, is a relevant tool for a first screening for genetic variation regarding novel traits of interest.  相似文献   

7.
The experiment was conducted using simple lattice design with two replication and the trails was totally consisted fifty six genotypes. Data on seed yield and other Agronomic traits were used to estimate the genetic variability parameters, heritability and genetic advance (GA). Analysis of variance revealed highly significant and significant difference for all studied traits. Evaluated characters were exhibited different levels of variability, heritability and genetic advance among the studied genotypes. Low to high phenotypic coefficient of variation (PCV) and genotypic coefficient of variation (GCV) were recorded. The highest GCV and PVC values were found particularly for lodging percent (76.65% and 90.63%), harvest index (42.26% and 47.92%) yield per hectare (41.23% and 48.19%) and number of capsule per branch (30.81% and 37.25%) respectively, whereas low GCV and PCV (8.27% and 9.73% respectively) manifested for days to maturate. The highest broad sense heritability value manifested for harvest index (77.78%) followed by seed yield per hectare (73.21%), while lowest heritability (3.78%) revealed only for seed per capsule. In present study low to moderate genetic advance were manifested and high heritability and genetic advance as percentage of mean (>50) was recorded for lodging percentage, number of capsule per branch, seed yield per hectare and harvest index, indicating predominance of additive gene action for these characters. Therefore the result of this study suggests existence of variability for seed yield and other agronomic traits in these linseed genotypes, which should be exploited in future breeding.  相似文献   

8.
基于因子分析和聚类分析的甘蔗品种抗螟性评价   总被引:1,自引:0,他引:1  
为明确甘蔗品种(系)抗螟性评价指标,建立甘蔗品种(系)抗螟性综合评价体系。在田间自然虫源条件下,以螟害株率、螟害节率、螟害指数、枯梢率、蛀道数、蛀道长度和羽化率为甘蔗生长中后期抗螟性评价候选指标,对19个甘蔗新品种(系)的抗螟性进行因子分析和聚类分析。结果表明:除螟害株率外,其余6个候选指标均有望作为抗螟性评价指标,其中螟害指数与单茎重损失量、蔗糖分损失量间同时具有显著正相关,是评价甘蔗受害程度的最佳指标。因子分析结果表明,6个抗性相关指标可简化为3个公因子,即植株受害因子、蛀道解剖因子和螟虫生长发育因子。根据品种因子得分,对19个甘蔗新品种(系)抗螟性进行系统聚类分析,结果显示,粤甘42号对螟虫抗性最高,福农38号、桂糖29号、柳城03-1137和桂糖31号对螟虫抗性最低。本研究结果不仅提供了甘蔗抗螟性评价指标与综合抗性评价方法,还明确了19个甘蔗新品种(系)对甘蔗螟虫的抗性。  相似文献   

9.
10.
中国粳稻地方种资源核心样品的构建方法研究   总被引:15,自引:0,他引:15  
以《中国稻种资源目录》中的16 791份中国粳稻地方种为材料,根据完全随机、变种类型(丁颖分类法)下随机和系统聚类3种取样方法和4种核心样品规模(12.5%、10%、7.5%和5%)设计12个核心样品,以8个编目性状的平均数变幅、方差和变异系数加以评价。结果表明:(1)变种类型下系统聚类取样方法是构建中国粳稻地方种资源核心样品的适宜方法;(2)样品规模5%的核心样品可以有效地代表中国粳稻地方种资源的总体样品。  相似文献   

11.
芝麻资源核心收集品的建立   总被引:4,自引:2,他引:2  
通过对预选出的884 份芝麻资源核心收集品农艺性状的进一步鉴定核查和修正之后,采用离差平方和法分组进行系统聚类分析,依据决选核心收集品数量为预选核心品的50% 的原则、并考虑组间遗传多样性差异,随机挑选出453 份核心资源,建立了中国芝麻资源核心收集品。对453 份核心收集品代表性分析结果表明:核心资源的株型、花色等10 个非数值型性状共35 种表现型各占比例与预选核心品基本一致,含油量、千粒重等4 个数量性状的均值,标准差等6 个特征值与预选品相近  相似文献   

12.
20个云南无性系茶树良种的DNA指纹图谱构建   总被引:3,自引:0,他引:3  
以20个云南无性系茶树良种为材料,选用7对多态性丰富、品种区分率高、易统计的ISSR引物对茶树良种进行分析。结果显示,7对ISSR引物共扩增出110条带,其中多态带93个,多态条带比例为84.54%,多态信息量平均为0.417,品种相似性系数在0.574~0.854之间,其中引物UBC835,ISSR2不仅多态性丰富,且单个引物就可区分所有品种,是最有效的核心引物;7对核心引物两两组合的效率分析表明,UBC835/UBC811、ISSR2/UBC835和UBC835/ISSR3是高效引物组合,可以完全有效区分所有品种,且品种相似性系数较低;同时使用15个地方品种验证3个高效引物组合,结果表明,UBC835/ISSR2是最佳引物组合,不仅能有效区分所有云南无性系茶树良种,而且能将云南无性系良种与15个地方品种最有效地区分开。使用品种的国家地区代码、育种单位英文缩写、核心引物名称和分子数据组成云南无性系茶树良种的DNA指纹图谱,不仅包含了品种的重要信息,而且其中的分子数据可用作茶树品种的真伪鉴定和遗传关系分析,为茶树品种的知识产权保护提供有效的科学依据。  相似文献   

13.
A core collection of 372 accessions representative of worldwide hexaploid bread wheat diversity [Balfourier, F., Roussel, V., Strelchenko, P., Exbrayat-Vinson, F., Sourdille, P., Boutet, G., Koenig, J., Ravel, C., Mitrofanova, O., Beckert, M., Charmet, G., 2007. A worldwide bread wheat core collection arrayed in a 384-well plate. Theoretical and Applied Genetics 114, 1265–1275] was used to evaluate the available genetic diversity of agronomic and quality characteristics. The traits assessed during the vegetative period were date of ear-emergence, date of flowering, lodging, disease susceptibility and pre-harvest sprouting. Thousand kernel weight, test weight, grain hardness, grain protein content, pentosan viscosity and grain colour were also measured. The rheological properties of the derived white flours were estimated using mixograph and alveograph tests. For most of the traits, a wide phenotypic variation was observed across all the accessions. Several parameters (mixograph width parameters before and after peak time, alveograph dough tenacity and extensibility, near infrared measurements, like those for protein content, and absorbance measurements of palmitic acid and linoleic acid content) made it easier to discriminate between the cultivars. The largest ranges of variation were found in landraces and old cultivars rather than in more recent varieties. This is evidence that there is sufficient variability available for rare alleles, which have been eliminated in breeding modern varieties to be detected. Such a core collection will therefore be a useful resource for future genetic studies on wheat quality.  相似文献   

14.
A core collection of 372 accessions representative of worldwide hexaploid bread wheat diversity [Balfourier, F., Roussel, V., Strelchenko, P., Exbrayat-Vinson, F., Sourdille, P., Boutet, G., Koenig, J., Ravel, C., Mitrofanova, O., Beckert, M., Charmet, G., 2007. A worldwide bread wheat core collection arrayed in a 384-well plate. Theoretical and Applied Genetics 114, 1265–1275] was used to evaluate the available genetic diversity of agronomic and quality characteristics. The traits assessed during the vegetative period were date of ear-emergence, date of flowering, lodging, disease susceptibility and pre-harvest sprouting. Thousand kernel weight, test weight, grain hardness, grain protein content, pentosan viscosity and grain colour were also measured. The rheological properties of the derived white flours were estimated using mixograph and alveograph tests. For most of the traits, a wide phenotypic variation was observed across all the accessions. Several parameters (mixograph width parameters before and after peak time, alveograph dough tenacity and extensibility, near infrared measurements, like those for protein content, and absorbance measurements of palmitic acid and linoleic acid content) made it easier to discriminate between the cultivars. The largest ranges of variation were found in landraces and old cultivars rather than in more recent varieties. This is evidence that there is sufficient variability available for rare alleles, which have been eliminated in breeding modern varieties to be detected. Such a core collection will therefore be a useful resource for future genetic studies on wheat quality.  相似文献   

15.
采用二次通用旋转组合设计优化玉米子粒耐破碎性测定方法与参数,提高测定准确率和辨识度。实验选定碾磨时间(X_1)、旋转速度(X_2)、测定子粒质量(X_3)为考察因素,以子粒破碎率为考察指标,采用二次通用旋转组合设计优化子粒耐破碎性测定方法与参数。实验优化所得玉米子粒耐破碎性测定的最佳参数为碾磨时间80 s,转速1 200 r/min,测定子粒质量30 g,在此条件下,玉米品种郑单958和新引M751子粒破碎率差值为4.07。优化所得的测定子粒破碎率的方法及参数稳定可行。  相似文献   

16.
不同气候生态条件下稻米品质性状的变异及主要影响因子分析   总被引:109,自引:0,他引:109  
 通过多个不同类型品种的分期播种试验,分析了稻米品质诸性状在不同播期气候生态条件下的变异特征,并利用偏相关分析法对水稻灌浆结实期间若干气候生态因子的相对重要性进行综合评价。结果表明,稻米品质各性状可根据在不同播期条件下的变异系数大小划分为3种类型,其中垩白度对气候条件变化最敏感,粒形、粒长等性状较迟钝,而整精米率、胶稠度、直链淀粉含量等性状居中;同一品种晚播与早播相比,一般稻米的垩白度小、整精米率高、碱解值大,而直链淀粉含量的表现则与品种本身直链淀粉含量的高低有关;在影响稻米品质的诸气候生态因子中,水稻灌浆结实期间的日平均温度的作用最大,日平均太阳辐射、日平均温差和平均日照时数次之,而日平均相对湿度和日平均降雨量最小。  相似文献   

17.
PEG-6000胁迫下玉米品种萌发期抗旱性鉴定与评价   总被引:5,自引:4,他引:1  
以收集的52个推广应用的春播玉米为供试材料,运用渗透压为0.5 MPa的PEG-6000模拟干旱胁迫,测定各品种发芽率、耐旱萌发指数等10个鉴定指标。以鉴定指标的相对值作为抗旱性评价指标,应用多种分析方法对各指标进行比较分析并对品种进行综合评价和分类。结果表明,干旱胁迫下各指标均受到不同程度的影响,其中,发芽势可用于玉米萌发期抗旱性的快速与初步鉴定。发芽势、发芽率、发芽指数与耐旱萌发指数4项指标可作为抗旱能力的主要鉴定指标,种子吸水率与胚根胚芽长、贮藏物质运转率可作为间接抗旱鉴定指标。根据供试品种隶属函数值,利用聚类分析将其分为4个不同的耐旱等级,筛选出17个抗旱型品种。  相似文献   

18.
播种后遭遇渍害是南方夏大豆生产面临的主要逆境危害之一。为研究不同大豆种质播后对浸水耐性差异表现,以种子浸种120h模拟渍害条件,测定137份大豆材料浸泡液电导率,并进行标准发芽试验,统计种子发芽势(GPP)、发芽率(GP)、正常苗率(NSP)等指标,并利用主成分分析、聚类分析等分析方法对多个指标进行多元统计分析,利用综合耐浸水指标及简易指标对大豆种子耐浸水能力进行等级划分,筛选耐浸水能力强的大豆材料。结果表明,浸水处理120h后,GPP、GP、NSP、轻微损伤粒率(SISP)、严重损伤粒率(IBSP)、烂粒率(DSP)及电导率等6个指标的变异系数均大于50%,GPP、GP和NSP同大豆百粒重呈显著负相关,电导率同百粒重呈显著正相关。利用主成分分析提取两个主成分:“健康因子”和“过渡因子”,贡献率分别为64.45%和15.83%,根据两因子得分矩阵进行聚类分析,可将供试材料划分为3类。利用综合指标法将137份大豆材料划分为5种耐浸水级别,表现耐浸水的大豆材料9份,并在GP、GPP、NSP三个简易耐浸水指标筛选中同时表现耐浸水的大豆材料5份,可作为进一步筛选鉴定的对照种质资源。大豆浸泡液电导率与种子正常苗率相结合可作为大批量筛选耐浸水种质的指标。  相似文献   

19.
水稻发育期模型的比较   总被引:6,自引:0,他引:6  
通过对CERES-rice、ORYZA2000、RCSODS、RiceGrow等模型中发育期模型的比较与分析,揭示了这些模型在发育速率对温度的响应模式、发育期阶段划分与参数设置、日长效应模式的差别,分析了累积生长度日、发育生理日及发育速率的关系。研究表明,4个模型的发育速率对温度的响应模式基本一致;CERES-rice、ORYZA2000、RiceGrow在基本营养生长期和籽粒灌浆期参数设置一致,而在光敏感期虽然都有3个参数(发育速率、临界日长、日长效应系数),但CERES-rice和Rice-Grow中各有一个参数固定,穗发育期CERES-rice和RiceGrow均没有引入新参数,而ORYZA2000则引入新参数;CERES-rice、RCSODS和ORYZA2000的日长效应模式基本一致,而与RiceGrow差异较大。RCSODS中的发育期模型阶段划分较为简单,参数较少;ORYZA2000模型最为通用,但参数较多,且仅根据发育期资料无法唯一确定。  相似文献   

20.
热力学特性是评价鲜食糯玉米子粒均匀性、热稳定性和回生程度的重要指标。为了解我国鲜食糯玉米品种热力学特性,利用差示扫描量热法(DSC)测定104个鲜食糯玉米品种的热力学特性,并采用主成分分析方法对其结果进行评价。结果表明,鲜食糯玉米104个品种间淀粉热力学特征参数有显著差异,且不同参数中以回生值变异最大,回生样品的终值温度变异最小。相关分析表明,糯玉米淀粉胶凝特征参数起始温度、峰值温度、终值温度两两极显著正相关,糊化范围与峰值指数呈极显著负相关,回生热焓值和回生值呈极显著正相关。将热力学特征参数可简化为4个主成分,累计方差贡献率为86.11%。104个糯玉米品种可分为8大类,其中I和II类分别有53和43个品种,共占供试材料的92.3%,是最主要的两种类型。糯玉米淀粉热力学特征值间有良好的相关性,影响鲜食糯玉米子粒品质最重要的热力学特征值为回生值、热焓值和胶凝温度。  相似文献   

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