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101.
Mohammad Reza Naghavi Mohsen Mardi Seyed Mostafa Pirseyedi Mehrbanu Kazemi Payam Potki Mohammad Reza Ghaffari 《Genetic Resources and Crop Evolution》2007,54(2):237-240
Genetic diversity of 54 accessions of Aegilops tauschii from five countries was assessed using sequence-tagged microsatellites (or simple sequence repeats, SSRs) and amplified fragment
length polymorphisms (AFLPs). In the case of AFLP analysis, a total of 256 amplification products obtained, 234 of them were
polymorphic across all the 54 accessions. A total of 224 fragments were obtained from the 24 SSR primers and 219 of fragments
were polymorphic across all the genotypes screened. Based on both AFLP and SSR markers, the highest percentage of polymorphisms
were obtained in Iranian and accessions of unknown origin. The highest polymorphic information content (PIC) value was observed
for SSRs (0.82) while the highest marker index (MI) value was for AFLPs (8.5) reflecting the hyper-variability of the first
and the distinctive nature of the second system. Principal co-ordinate analysis (PCO) revealed congruent patterns of genetic
relationships for both data sets, but did not group accessions strictly according to their geographical origins. Poor correlation
was found between AFLP and SSR marker loci. This low association may be due to low number of AFLP and SSR markers. These results
show that molecular markers can help to organize the genetic variability and expose useful diversity for breeding purposes. 相似文献
102.
Amer Ibrahim Basha Stefano Padulosi Kamel Chabane Adnan Hadj-Hassan Ehsan Dulloo Mario Augusto Pagnotta Enrico Porceddu 《Genetic Resources and Crop Evolution》2007,54(8):1807-1816
Pistachio (Pistacia vera L.) is a strategic nut tree species in the Middle East which holds comparative advantage over other fruit trees in view of
its hardiness, income generation opportunities and benefits for the ecosystem. Yet pistachio cultivation depends on a very
narrow genetic base, in spite of the existence of many varieties still marginally exploited. Syria is an important center
of diversity for pistachio. A country wide ecogeographic survey in this country was carried out to determine the extent of
pistachio genetic diversity and its use. As a whole, 114 accessions were collected from 37 farms to assess diversity at morphological
and molecular level. Molecular evaluation was carried out using Amplified Fragment Length Polymorphism (AFLP) technique and
performed using seven primer pair combinations. Results from the studies allowed the identification of 25 pistachio female
varieties in Syria, some of which unique and described for the first time. Three groups of pistachio diversity were identified
by cluster analysis which provides useful information about the distribution of genetic diversity in Syria for enhanced use
and sustainable conservation. 相似文献
103.
野生种抗豆象绿豆种质资源TC1966对多个豆象小种均具有很好的抗虫性。通过对抗虫亲本TC1966、感虫亲本绿1号及以中绿1号为轮回亲本经多代回交后获得的3个近等基因系材料进行抗虫鉴定.结果轮回亲本中绿1号的种子被害率〉90%.表现高感(HS);抗性亲本TC1966及三个高代材料种子被害率〈10%,表现高抗(HR).说明抗虫亲本TC1966中的抗虫基因呈显性遗传,且能够在后代材料中稳定遗传和表达。本文利用AFLP分子标记技术对该5份试验材料进行了多态性指纹图谱分析.结果从830对AFLP引物组合中筛选出在抗、感虫材料间表现多态性的引物组合100对。将部分多态性AFLP特异扩增条带从聚丙烯酰胺凝胶上回收,然后将二次扩增产物进行测序,并通过同源性序列比较的手段进行了相关生物信息学分析。本研究为今后进一步开展抗豆象基因的AFLP分子标记及其转化研究乃至抗豆象基因的克隆工作提供参考依据。 相似文献
104.
xu@hotmail.com 《勤云标准版测试》2006,(5)
利用AFLP分子标记技术,从DNA水平对人工三倍体新桑品种嘉陵16号(2n=3x=42)及其亲本进行了遗传背景分析。获得了它们的指纹图谱、遗传距离及遗传相似系数,并绘制出了它们的UP-GMA聚类图。研究结果发现:嘉陵16号的母本西庆一号(4X;♀)与父本育二号(2X;♂)之间的遗传相似系数为0.6607。这为今后更具强大杂交优势和多倍体优势的新型人工三倍体新桑品种选育时杂交亲本的选择与组配提供了较有用的参考依据。 相似文献
105.
以日系家蚕品种"湘晖"和"872"为亲本进行杂交,从 F2代分别向茧丝量高(A)、中(B)、低(C)3个方向进行定向选择.经过F2~F6共5代的同蛾区交配和选择,获得了茧丝量性状有显著差异的A,B,C共3个家系.以中系蚕品种芙蓉、菁松及其杂交后代为参照群体,对3个杂交分离系进行AFLP分析,获得了617个AFLP分子标记.结果显示:选择到F4代时,A,B,C各杂交分离系的AFLP分子标记表现出一定的差异,到F6代时,A,B,C各杂交分离系间的分子标记差异十分显著且稳定.利用UPGMA法进行聚类分析的结果也显示有很强的规律性,所有个体均按家系有规律地聚在一起.从分子水平证明家蚕同蛾区杂交后代系统选择到F6代即可获得遗传性稳定的不同杂交分离系. 相似文献
106.
107.
108.
109.
Opaque endosperm is the main phenotypic indicator for waxy rice, but other phenotypic and genotypic variation among waxy rice
accessions has largely been ignored. Previous studies showed that wide diversity in starch physiochemical properties exists
in both indica and japonica waxy rices, especially for starch gelatinization temperature (GT) which could be divided into a high- and a low-GT group.
In the present study, amplified fragment length polymorphism (AFLP) and inter-simple sequence repeat (ISSR) molecular markers
were employed to examine genetic diversity and relationships of 56 waxy rice accessions. A total of 358 AFLP fragments were
amplified with five primer combinations, showing a high level of polymorphism (78.3%). A total of 190 ISSR bands were generated
with a single primer and a primer pair, showing a very high level of polymorphism (92.2%). The genetic distance matrices obtained
from the two sets of markers were significantly correlated (r = 0.731, P = 0.004). The dendrogram generated with combined AFLP and ISSR markers could clearly differentiate the indica and japonica groups. Newly released varieties and breeding lines within each subspecies tended to be clustered together, whereas landraces
were more distantly placed in the dendrogram. Only one AFLP band was found specific to the indica type, while no specific bands were found for starch GT. The implications for the conservation and breeding of waxy rice are
discussed. 相似文献
110.
M.?Vetel?inenEmail author E.?Gammelg?rd J.?P.?T.?Valkonen 《Genetic Resources and Crop Evolution》2005,52(8):999-1010
The management of genebank collections of cultivated potato is costly due to the need for in vitro maintenance and virus eradication. Therefore, it is important to set up conservation strategies, which prevent duplicates
entering the collections. In this study, 32 Nordic potato landraces were studied for 57 morphological traits and analysed
for amplified fragment length polymorphism (AFLP). Most landraces could be distinguished based on the morphological characters,
except five accessions. Using five primer combinations to generate 114 reproducible AFLPs, of which 63 (55%) were polymorphic,
the five morphologically indistinguishable accessions were placed into two groups with identical AFLP patterns, suggesting
that some of the accessions were redundant for long-term preservation. The AFLP data showed that the Nordic collection of
potato landraces is composed of genetically different clones, and morphological analysis revealed a wide range of variability.
This variability seems to be distributed randomly over the Nordic region since the cluster analysis based on AFLPs and morphological
traits revealed no grouping based on the country of origin. Principal component analysis suggests that fewer morphological
traits than used in this study will be sufficient to discriminate between different genotypes of cultivated potato (Solanum tuberosum L.). Future possibilities for rationalising potato collections are discussed. 相似文献