共查询到20条相似文献，搜索用时 484 毫秒
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NCBI的dbEST数据库中2 204条牡丹EST序列经过预处理获得2 048个高质量的序列,经拼接,获得318个Contigs和636个Singlets.其中142条拼接序列共检测出167个微卫星(简单序列重复,SSR),平均1.18个SSR/Contig或Singlet.这些微卫星从二至四核苷酸重复都有出现,二、三核苷酸重复类型占多数(97.61％),其中二核苷酸重复为46.71％,三核苷酸重复为50.90％.二核苷酸重复类型中出现最多的是AG/TC和GA/CT,分别占SSR总数的20.36％和16.77％,三核苷酸重复类型以AGA/TCT、GAT/ATC最多,分别占总SSR的5.40％.最后对含有微卫星的Contigs和Singlets进行基因注释、功能分类. 相似文献
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We report on the development of novel simple sequence repeat (SSR) markers from publicly available Cucumis sativus expressed sequence tags (ESTs) and on their transferability among related species. In total, 533 di- to penta-type SSRs were identified from 6344 cucumber ESTs retrieved from GenBank. Identified SSRs mainly comprised of di- and tri-nucleotide repeats, of which AG and AAG motifs were much abundant. A total of 392 SSR-containing unigenes (non-redundant ESTs/consensus sequences) were suitable for primer design. From these, 35 primer pairs were designed as representative samples and 28 were usable markers. Twenty-six out of 28 usable markers revealed polymorphism among 21 cucumber accessions with 2–7 alleles detected (mean = 3.77) and their polymorphism information content (PIC) values ranged from 0.091 to 0.748 (mean = 0.388). The polymorphism observed herein partially arose from the null alleles which occurred at the multiple homoeoloci detected by the markers. Transferability of the 28 EST-SSR markers was investigated in four other cucurbits: melon, watermelon, pumpkin and gourd which showed frequency of 92.9%, 57.1%, 53.6% and 60.7%, respectively. The EST-SSR markers developed herein will complement the currently available genomic SSR markers and may be useful for genetic studies in cucumber and related species. 相似文献
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Eighty-one accessions representing apricot germplasm in Tunisia were collected from different areas of cultivation and fingerprinted using amplified fragment length polymorphism (AFLP) and microsatellites (SSR) markers. A total of 339 polymorphic markers were revealed using 5 AFLP primers combinations and 24 SSR loci. AFLP and SSR markers expressed a high level of polymorphism allowing the distinction of the accessions with an efficiency coefficient of discrimination of 100% for AFLP and 97% for SSR markers. Genetic diversity structure was assessed with AFLPs and SSRs markers separately then with combined matrix data by the help of hierarchical clustering elaborated using Wards method based on Nei and Li (1979) distances. Comparison of the obtained dendrograms revealed a phylogeographic structure into two major groups with significant conservation between the observed subgroups in relation with the geographic origin of the accessions. The relative efficiency of the markers in determining the genetic relationships among apricot accessions has been assessed and a combination of AFLPs and SSRs markers was the most effective. In addition, Mantel test based on genetic distances indicated highly significant correlation between AFLP-SSR data and each of the AFLP and SSR ones, with Pearson correlation values of r = 0.873 and r = 0.692, respectively, revealing the higher efficiency of the combination of both molecular techniques (AFLP and SSR) to estimate the levels of genetic variability among apricot germplasm. 相似文献
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毛竹EST资源SSR标记分析与筛选 总被引：3，自引：2，他引：1
对来源于NCBI公共数据库的非冗余3 087条毛竹（Phyllostachys edulis）EST序进行简单重复序列SSR搜索发现：在401条毛竹EST序列中共查找到408个SSR位点,平均6.8 kb EST序列中含有1个SSR。其中二核苷酸和三核苷酸重复是毛竹EST-SSR的主要重复类型,分别占SSR总数的43.14%和49.75%。SSR的不同重复基序中,最常见的重复基序是：(AG)n,占37.01%,其余出现频率较高的依次为(TC)n、(AGC)n、(GAG)n和(CGC)n。根据搜索结果设计了182条毛竹EST-SSR引物,以12个不同种属的竹子DNA为模板,对引物进行了稳定性、通用性的验证与评价。结果表明有42对引物有较清晰且稳定的目标扩增产物,其中39对引物的产物存在多态性,说明设计开发的毛竹的EST-SSR标记是可行且有效的。 相似文献
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核桃EST-SSR信息分析与标记的初步建立 总被引：8，自引：0，他引：8
利用生物信息学方法,从dbEST数据库用SSRHunter软件对4 500条核桃EST序列进行搜索,发现462个SSR分布于399条EST序列中,EST-SSR出现频率10.27%,平均每5.65 kb EST出现一个SSR。核桃二核苷酸重复基元占主导地位,其次为三核苷酸重复基元,分别占总SSR的49.57%和27.27%。核桃二核苷酸EST-SSR的优势类型为AG,其次为AT,分别占二核苷酸SSR的67.25%和28.38%。核桃三核苷酸EST-SSR的优势重复基元为AAG,其次为ACC、AAT、AGG,分别占三核苷酸SSR的25.40%、21.43%、16.67%和11.11%。用Primer Primer 5.0软件设计了11对引物,对核桃属5个样品进行PCR扩增,10对引物有扩增产物,引物有效扩增率90.9%,其中7对引物有多态性,多态性引物占可扩增引物的70%。表明,利用核桃EST序列开发EST-SSR标记是可行的。 相似文献
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利用SSRIT软件对NCBI上蝴蝶兰的8 188条EST序列按照碱基重复单元数8以上的标准进行SSR位点查找,发掘出246条EST序列,共含有261个SSR位点,检出率为3.19%。二核苷酸重复是最主要的重复类型,占SSR总数的94.25%。SSR的不同重复单元中,最常见的重复单元是：(TA)n和(GA)n,其余出现频率较高的依次为(TC)n、(AT)n和(AG)n。设计了32对EST-SSR引物,以蝴蝶兰品种‘V31’的DNA为模板进行PCR扩增,发现16对引物能扩增出预期产物。进一步用这16对引物对16个蝴蝶兰品种（系）进行PCR扩增,9对引物有多态性,多态性条带数在2 ~ 12个之间。结果表明,设计开发的蝴蝶兰的EST-SSR标记是有效的。 相似文献
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菜薹转录组中SSR信息与可用性分析 总被引：1，自引：0，他引：1
利用菜薹转录组分析检测到48 975条unigene（38.17 Mb）序列数据,运用MIcroSAtellite（MISA）工具发现其中具有1 ~ 6个核苷酸重复类型的SSR位点11 879个,SSR位点发生频率为1/3.2 kb（312.5/Mb）。6种SSR位点类型中主要为1 ~ 3个核苷酸重复,占总SSR位点数的99.01%,其中单、二和三核苷酸类型分别为41.11%、28.23%和29.67%。发现重复序列的基序58个,重复次数在5 ~ 23之间,其中出现频率高的基序主要有A/T、AG/CT、AT/AT、AC/GT、AAG/CTT和AGG/CCT。重复序列长度在10 ~ 60 bp之间,大多小于20 bp,大于20 bp的仅有7.9%（938个SSR位点）。设计出676对具有潜在多态性的SSR引物组合,从中随机抽取30对引物进行PCR扩增验证其可用性,发现22对引物在4份菜薹种质中的扩增产物条带清晰稳定,其中12对引物具有多态性。 相似文献
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白菜EST-SSR信息分析与标记的建立 总被引：35，自引：6，他引：35
数量迅速增加的EST为开发新的SSR标记提供了宝贵的资源。本研究对4 584条白菜EST进行了搜索, 共检索出474个SSR, 检出率为10.3% , 包括40种重复基元。其中二核苷酸和三核苷酸重复单元的EST-SSR占主导地位, 二者出现的频率基本相近, 占总SSR的近83%; 其它重复类型所占比例均不足5%。GA和GAA是二、三核苷酸中的优势重复类型, 分别占二、三核苷酸重复类型的71.5%和37.5%。设计了15对EST-SSR引物, 在合适的PCR反应体系下, 以构建EST的白菜自交系A的DNA为模板, 对设计的EST-SSR引物进行筛选, 发现15对EST-SSR引物都能扩增出产物。进一步用这些可扩增的引物对28个白菜品种进行PCR扩增, 发现7对引物显示多态性, 占引物总数的46.7%。此结果表明, 根据EST建立EST-SSR标记是一条简便而又有效的途径。 相似文献
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基于EST信息的百合SSR标记的建立 总被引：19，自引：6，他引：13
依据已知的百合EST（expressed sequence tags）序列信息,开发新的SSR(simple sequence repeats)标记,在NCBI的EST数据库1 688 EST中检索到98条含有101个SSR的序列, SSR的检出率为5.98%,其中三核苷酸重复类型占主导地位,出现频率为2.84%。EST-SSR的重复基元共搜索到47种,其中三核苷酸重复基元类型最为丰富,大约占重复基元类型总数的一半。利用部分EST-SSRs序列共设计23对SSR引物, 以铁炮百合‘Snow Queen' DNA为模板,对引物进行筛选,其中18对引物有扩增产物,占所设计引物总数的78.26%;进一步用这些引物在5个杂种系列13个百合品种进行多态性测试,显示多态性的引物占可扩增引物的66.7%。本研究结果证明了基于百合EST信息建立SSR标记是一种有效而又可行的方法。 相似文献
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南方红豆杉转录组SSR挖掘及分子标记的研究 总被引：4，自引：0，他引：4
利用Trinity软件对NCBI公共数据库中公布的南方红豆杉（Taxus chinensis var. mairei）根、茎和叶的转录数据进行转录组的重新拼接。通过对13 737 528条序列组装得到96 279条Unigenes（38 Mb）,通过SSR检测程序从96 279条Unigenes中得到2 160个SSR位点（2.24%）,其平均发生率为1/18.01 kb,基序长度为14 ~ 25 bp之间。优势重复基序为六核苷酸和三核苷酸,分别占总SSR位点的38.56%和37.08%。2 160个SSR位点由703种重复基序构成,其中六核苷酸占60.96%,主要分布在3 ~ 4重复;二、三核苷酸占总SSR位点的44.81%,其中以（AG/CT）n、（AT/AT）n、（AAG/CTT）n、（AGC/CTG）n、（AGG/ CCT）n 和（ATC/ATG）n重复基序最为丰富,合占总SSR重复类型的34.73%,并出现少量的（CG/CG）n和（CCG/CGG）n重复。通过L9（34）正交试验得到最优的SSR-PCR体系,10 μL PCR体系中含DNA 20 ng,1× PCR缓冲液,MgCl2 20 mmol,dNTPs 0.35 mmol,引物0.25 μmol,Taq酶0.45 U。随机挑选62对SSR引物进行8个南方红豆杉株系的SSR扩增,有效扩增率为53.23%,多态性比率为38.71%。这些多态性转录组SSR引物的开发为红豆杉遗传多样性的分析、分子标记辅助育种、遗传图谱构建和功能基因的挖掘提供了更丰富的标记。 相似文献
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The culture of isolated microspores of kale (Brassica oleracea var. acephala) was studied including the importance of genotype to embryo regeneration, medium composition chiefly the sucrose concentration and the use of colchicine, simultaneously medium renovation. It was initiated using 29 different genotypes as donor plants. Embryos were induced from six of the kale genotypes and these corresponded to the more out-bred genotypes. Embryogenesis was achieved using four different combinations of culture media: (a) microspores initially cultured in NLN medium supplemented with 13% (w/v) sucrose (NLN-13) for 48 h, followed by transfer to fresh NLN-13 medium; (b) microspores cultured for 48 h in NLN-13 medium supplemented with colchicines (50 mg/L) followed by transfer to unsupplemented NLN-13 medium; (c) microspores cultured for 48 h in NLN-16 medium supplemented with colchicines (50 mg/L) followed by transfer to unsupplemented NLN-16 medium; (d) microspores cultured for 48 h in NLN-16 medium supplemented with colchicines (50 mg/L) followed by transfer to unsupplemented NLN-13 medium. The embryos obtained from four of the genotypes developed into plantlets and these regenerated plants have been successfully transplanted to soil. 相似文献
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利用MISA软件筛选黄皮（Clausena lansium）转录组测序获得的68 998条Unigene,共检测出单核苷酸至六核苷酸重复类型的SSR位点11 825个,分布于11 000条Unigene中,出现频率为17.14%,平均分布距离为4.41 kb。6种SSR位点类型中主要为单、二、三个核苷酸重复,分别占总SSR位点的41.48%、24.92%和27.53%。11 825个SSR位点中共发现207种重复基序,重复次数在4 ~ 24次之间,其中出现频率高的基序有A/T、AG/CT、AT/AT、AAG/CTT和AAT/ATT。位点序列长度分布在12 ~ 25 bp之间,其中12 ~ 15 bp最多,占50.95%（6 025个SSR位点）。通过Primer 3设计得到6 102对SSR引物,随机选择30对引物进行多态性验证分析,结果显示24对有效扩增引物中,13对引物在16份不同黄皮种质中表现出多态性。以上结果表明,黄皮转录组测序产生的Unigene信息可作为开发SSR标记的有效来源,开发的大批量SSR标记可为黄皮种质资源遗传多样性分析和遗传图谱构建提供更加丰富可靠的标记选择。 相似文献
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Effects of interlighting on yield and external fruit quality in year-round cultivated cucumber 总被引：1，自引：0，他引：1
The effects of interlighting and of the proportion of interlight on the yield and fruit quality of year-round cultivated cucumber (Cucumis sativus L. cv. Cumuli) were investigated for this study. Artificial lighting was provided by high pressure sodium (HPS) lamps and the lighting regimes included top lighting (TL), top + interlighting 24% (T + IL24) and top + interlighting 48% (T + IL48). In TL, all of the lamps were mounted above the canopy. In T + IL24 and T + IL48, top lamps covered 76 and 52% of the lighting, respectively, while 24 and 48% of the lighting came from interlighting lamps which were mounted vertically 1.3 m above the ground between the single plant rows. The outdoor daily light integral (DLI) varied greatly during the cultivation periods; the mean values were 36.8, 5.3 and 19.9 mol m−2 day−1 for the summer, autumn–winter and spring stands, respectively. Lighting regime affected both yield and external fruit quality. Interlighting increased first class yield and decreased unmarketable yield, both in weight and number. The increase in the annual first class yield in weight was 15% in the two T + IL regimes. Interlighting improved energy use efficiency in lighting, being for the whole year 120, 130 and 127 g total yield kW h−1 in TL, T + IL24 and T + IL48, respectively. Interlighting increased the fruit skin chlorophyll concentration in all seasons, but had only a minor effect on the fruit dry matter concentration. The mean total chlorophyll concentration in fruit skin was 70.8, 76.7 and 82.2 μg cm−2 in TL, T + IL24 and T + IL48, respectively. In addition, interlighting extended the post-harvest shelf life of cucumber fruits in spring. Besides interlighting per se, also the higher proportion of interlight tended to further improve the fruit quality. For example, the fruit skin chlorophyll concentration increased along with the higher proportion of interlighting. In general, the effects of lighting regime were more prominent in lower natural light conditions in winter and spring. It is concluded that interlighting is a recommendable lighting method in cucumber cultivation, especially in lower natural light conditions. 相似文献
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Sogo Nishio Toshiya YamamotoShingo Terakami Yutaka SawamuraNorio Takada Chikako NishitaniToshihiro Saito 《Scientia Horticulturae》2011
A total of 366 novel simple sequence repeat (SSR) markers were developed in Japanese chestnut (Castanea crenata), comprising 220 genomic SSRs derived from enriched genomic libraries and 146 expressed sequence tag (EST)–SSRs obtained from large-scale EST sequencing analysis. Thirty accessions, comprising Japanese, Chinese (C. mollissima), European (Castanea sativa), and American chestnuts (Castanea dentata), were used for evaluation of SSR polymorphism and transferability across species. The EST–SSRs showed less polymorphism than the genomic SSRs and were more transferable. The mean observed heterozygosity (HO) and the mean expected heterozygosity (HE) of genomic SSRs in the Japanese chestnuts were 0.63 and 0.68, respectively; those of EST-SSRs were each 0.47. Although about 80% of the genomic SSRs were amplified in all 4 species, more than 95% of the EST–SSRs were transferable across all 4 species. The many novel SSRs developed in this study will be applicable for the construction of genetic linkage maps, QTL analysis of phenotypic traits, high-throughput genotyping of marker-assisted selection, and association genetics. 相似文献
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蓝靛果忍冬转录组SSR信息分析及其分子标记开发 总被引：1，自引：0，他引：1
利用MISA软件筛选蓝靛果忍冬（Lonicera caerulea L.）转录组测序获得的45 656条Unigene,共检测出14 841个SSR位点,分布于11 251条Unigene中,出现频率为32.51%,平均分布距离为2.58 kb。优势重复基序为单核苷酸、二核苷酸和三核苷酸,分别占总SSR位点的34.81%,42.79%和20.64%。二核苷酸重复基元中以AG/CT为优势重复基元,占总位点27.2%,三核苷酸重复基元以AAG/CTT为主,占6.18%。利用 Primer 3.0 共设计出 21 867 对SSR引物。随机选择20对引物进行PCR扩增,其中8对扩增出清晰可重复的条带,5对在16个蓝靛果忍冬材料中表现出多态性。利用UPGMA作图,将16份供试材料分为3类。丰富的SSR多态性为蓝靛果忍冬遗传多样性分析和遗传图谱构建提供更加丰富可靠的标记选择。 相似文献
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Ghada Baraket Ahmed Ben Abdelkrim Olfa Saddoud Khaled Chatti Messaoud Mars Mokhtar Trifi Amel Salhi-Hannachi 《Scientia Horticulturae》2010
The trnL (UAA) intron and the intergenic spacer between the 3′ exon of trnL (UAA) and trnF (GAA) sequences were used as genetic markers for differentiating Ficus carica cultivars and establishing refined genetic relationships. The study was based on 20 fig cultivars, collected from south and centre of Tunisia. Since, the intron was thought to be more variable among close relatives than is the chloroplast spacer. The size of these non-coding regions varied from 554 to 589 and from 989 to 1022 bases pairs for the intron and the combined sequences correspondingly. The average of GC content was 33.9% and 34.6% in the intron and the combined intron and spacer respectively. High values of A + T contents were detected in both data sets and may explain the high proportions of transversions founded. The observed variation pattern of plastid DNA provides evidence of an important genetic diversity. The overall transition/transversion bias (R) was 0.202 in the intron and 0.27 in the combined regions. The RI index of 0.592 indicates that these combined sequences have clearly more homoplasy then the intron (RI = 0.705) and spacer (RI = 0.777) sequences separately. Phylogenetic trees were generated based on maximum parsimony (MP) and neighbor-joining (NJ) analysis of the chloroplast sequences data. Results proved that a typically continuous genetic diversity characterizes the local fig germplasm. In fact, relationships inferred from the cpDNA analysis suggest several clades, which do not show geographical or tree sex correspondence. Although the level of apparent diversity is considerable, we may conclude that non-coding regions of chloroplast genome provide a new and practical opportunity to evaluate genetic diversity and to discriminate fig cultivars. Revealed cytoplasmic DNA markers are reliable to elaborate a molecular data base to conduct management and breeding programs on local fig germplasm. 相似文献
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甜瓜EST-SSR位点信息及标记开发 总被引：3，自引：1，他引：2
对GenBank中35 547条甜瓜EST进行净化处理, 得到总长度为2.5 ×107 bp 的无冗余EST34 408条。从这些序列中发现2 877 个SSR, 分布于2 119 条EST中, 出现频率为8.36% , 分布密度为1/8.72 kb。单碱基、二碱基和三碱基重复是主导重复类型, 分别占EST2SSR总数的16.61%、22.49%和46.09%。A /T、AG/CT和AAG/CTT分别是单碱基、二碱基和三碱基的优势重复基元, 分别占15.88%、16.02%和28.61%。在所有的EST-SSR中, 69.10%的重复次数为4～10次, 51.34%的长度为12～20 bp。设计了30对EST-SSR引物, 分别对33份甜瓜自交系进行了PCR扩增, 24对引物能够扩增出期望长度的条带, 22对引物产物表现多态性, 平均每对引物能检测到2.73个等位基因。这些引物能比较准确地将甜瓜材料聚为不同类别。24对引物中, 有19对、16对和15对分别在黄瓜、西瓜和葫芦中通用。以上结果说明, 从甜瓜EST中开发SSR标记是一条简便、可行的途径。 相似文献