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1.
Temporal variation of diversity in Italian durum wheat germplasm 总被引:1,自引:0,他引:1
Giovanni Figliuolo Mariarosaria Mazzeo Ivana Greco 《Genetic Resources and Crop Evolution》2007,54(3):615-626
The aim of this work is to analyse the temporal change of genetic diversity in Italian durum wheat germplasm. The germplasm
deployed in this study (158 accessions), belonging to 5 different historical classes, was characterised for its microsatellite
and gliadin markers. The level of genetic diversity (He), based on gliadin and SSR markers results – on average – greater in indigenous landraces present in Italy before 1915, with
the exception of pure line material which had been selected from landraces (showing highest level of heterozigosity for gliadin
markers). Genotypes obtained from crosses or mutagenesis (referring to the 1950–1960 period) along with those resulting from
crosses between CIMMYT lines and old materials (1970s and beyond) were also genetically more diverse. Forty-nine percent of
indigenous landraces were genetically heterogeneous. Nine out of 53 landrace accessions were able to capture 4 different SSR
private alleles. It is speculated that the reduction of allele richness is an indicator of the genetic erosion of the pre-breeding
germplasm and it is pointed out that the implementation of appropriate methods of genetic conservation of this germplasm is
a priority for breeding and food safety. 相似文献
2.
A total of 242 accessions of common wheat (Triticum aestivum L.) released in China since the 1940s were evaluated with AFLP (amplified fragment length polymorphism) technique. Genetic diversity was analyzed using five pairs of polymorphic primer combinations with 245 polymorphic bands. The highest genetic diversity was found in the accessions of the 1950s, and in the next place was that in the 1940s. The genetic diversity began to descend in the 1960s, and fell to the lowest in the 1970s. After that, the genetic diversity came back to some extent in the 1980s, however, it became much lower in the 1990s compared with that in the 1940–1950s. Landraces and introduced accessions from foreign countries showed greater genetic diversity in comparison to improved varieties. In addition, greater genetic diversity was observed in winter wheat. It was emphasized that great attention should be paid on further exploration of genetic diversity in wheat breeding program. 相似文献
3.
4.
Abdelhameed Elameen Siri Fjellheim Arild Larsen Odd Arne Rognli Leif Sundheim Susan Msolla Esther Masumba Kiddo Mtunda Sonja S. Klemsdal 《Genetic Resources and Crop Evolution》2008,55(3):397-408
Sweet potato (Ipomoea batatas L.) is the fifth most important crop in the developing countries after rice, wheat, maize and cassava. The amplified fragment
length polymorphism (AFLP) method was used to study the genetic diversity and relationships of sweet potato accessions in
the germplasm collection of Sokoine University of Agriculture, Morogoro and Sugarcane Research Institute, Kibaha, Tanzania.
AFLP analysis of 97 sweet potato accessions using ten primer combinations gave a total of 202 clear polymorphic bands. Each
one of the 97 sweet potato accessions could be distinguished based on these primer combinations. Estimates of genetic similarities
were obtained by the Dice coefficient, and a final dendrogram was constructed with the un-weight pair-group method using arithmetic
average. AFLP-based genetic similarity varied from 0.388 to 0.941, with a mean of 0.709. Cluster analysis using genetic similarity
divided the accessions into two main groups suggesting that there are genetic relationships among the accessions. Principal
Coordinate analysis confirmed the pattern of the cluster analysis. Analysis of molecular variance revealed greater variation
within regions (96.19%) than among regions (3.81%). The results from the AFLP analysis revealed a relatively low genetic diversity
among the germplasm accessions and the genetic distances between regions were low. A maximally diverse subset of 13 accessions
capturing 97% of the molecular markers diversity was identified. We were able to detect duplicates accessions in the germplasm
collection using the highly polymorphic markers obtained by AFLP, which were found to be an efficient tool to characterize
the genetic diversity and relationships of sweet potato accessions in the germplasm collection in Tanzania. 相似文献
5.
Taro [Colocasia esculenta (L.) Schott] germplasm accessions collected from different parts of India were subjected to RAPD (Random Amplified Polymorphic DNA) analysis to assess the genetic diversity prevalent and also to test the genetic basis of morphotypic classification. Thirteen random decamer primers out of the 22 tested were used to analyse 32 taro accessions belonging to 28 morphotypes. Three out of these thirteen primers analysed showed 100 per cent polymorphism. Per cent polymorphism varied from 60 to 100 among the polymorphic primers. High genetic diversity was revealed as the similarity coefficient values ranged from 0.50 to 0.98. No two accessions analysed in the present study showed a similarity coefficient value of one thereby indicating their distinctness and presence of high genetic diversity in Indian taro germplasm. Dendrogram obtained from UPGMA analysis grouped 32 accessions in four clusters and three accessions were placed as outliers. Clustering pattern did not show any strict relationship with geographical distribution, morphotype classification and genotypic diversity. Further, accessions classified, as belonging to the same morphotypic group did not always cluster together. Presence of a very close genepool of the wild, weedy and cultivated forms with extreme levels of phenotypic and genotypic variation is suggested as the reason for high genetic diversity reported. Usefulness of DNA markers such as RAPD in characterising and assessing the genetic diversity in Indian taro germplasm is hereby demonstrated. 相似文献
6.
Sukyeung Lee Yu-Mi Choi Myung-Chul Lee Do Yoon Hyun Sejong Oh Yeonju Jung 《Genetic Resources and Crop Evolution》2018,65(6):1591-1602
Glutenin largely determines wheat bread baking quality. As high-molecular-weight glutenin subunit (HMW-GS), related to Glu-1 loci, determines wheat flour elasticity, it correlates strongly with bread-making quality. This study was aimed at clarifying genetic variations in bread-making characteristics between East and West Asian wheat landrace germplasms, by investigating HMW-GS allelic composition of 1068 wheat accessions. Herein, the accession number having reported HMW-GS pattern in previous studies was 855. However, the accession number with newly detected HMW-GS patterns was 114. These new HMW-GS patterns were classified into 4 types based on similarity. Eight Korean accessions with these four types were identified. Concerning landrace germplasm nature, 99 accessions showed heterogeneous patterns caused by seed mixture. The Glu-1 loci allelic variation analysis, revealed that the percentages of Glu-A1c (73.6%), Glu-B1b (60.2%), and Glu-D1a (68.5%) were highest at Glu-A1, Glu-B1, and Glu-D1 loci, respectively. The incidence of preferable alleles for bread baking was high in Chinese accessions. In bread-making quality evaluation using Glu-1 score, 24 among 35 accessions with full score were from China. The polymorphic information content index of each origin based on HMW glutenin subunit combination showed that West Asian and neighboring-regional landraces, excluding Afghanistan ones, were more diverse than East Asian landraces excluding Chinese ones. Cluster analysis based on Glu-1 allelic combination showed that many Korean, Japanese, and Afghan accessions were in the same group. However, many Chinese and other West Asian accessions were in the other group despite geographical distance. 相似文献
7.
Sevda Babayeva Zeynal Akparov Mehraj Abbasov Alamdar Mammadov Mohammad Zaifizadeh Kenneth Street 《Genetic Resources and Crop Evolution》2009,56(3):293-298
Diversity analysis was performed among 39 cultivated lentil (Lens
culinaris Medik.) accessions of Central Asia and Caucasian origin using five highly polymorphic microsatellite markers. A total of
33 alleles determined ranging from 3 to 8 per locus. Estimated gene diversity value for 33 loci was 0.66. Genetic similarity
indices among 39 accessions ranged from 0.24 to 1.0. Cluster analysis using the unweighted pair group method with arithmetic
mean method classified accessions into six major groups at 0.5 similarity coefficient. More than half accessions from Tajikistan
formed large cluster. On the other hand, a few accessions from each country showed unique genotypes. Overall, most of the
accessions, except ones with closely related origin, were distinguished by the present high quality DNA fingerprinting. This
molecular diversity information gives important basis for conservation strategy in gene bank and exotic germplasm introduction
in breeding programs in Central Asia and Caucasian countries. 相似文献
8.
Cornus officinalis is plant species that is widely used in traditional Chinese medicine. To help the efficient utilization and conservation of this species, the genetic diversity of 73 germplasm resources collected from Zhejiang, Henan and Shaanxi provinces in China were used in a primary core collection. The germplasm resources were classified nine types and the analysis of morphological traits and chemical components showed wide variations among the germplasm types. The primary core collection of C. officinalis was evaluated by using 18 inter-simple sequence repeat (ISSR) markers and a mini core collection was developed based on three strategies on construction of a core germplasm resources. The ISSR results showed that a total of 233 alleles were identified in these 73 accessions, the genetic diversity (P?=?91.02%, H?=?0.293, I?=?0.446) revealed with an average of 2 alleles per locus. The genetic diversity index analysis suggested that there is a great richness and uniqueness of genetic variation in this primary core collection. Cluster analysis by UPGMA and STRUCTURE placed the 73-germplasm resources into four linkage clusters. Almost all samples from one sampling location were clustered together. Compared to the RS and SW strategy, the LDSS strategy proved to be more representative in the core collection of C. officinalis. Finally, a mini core collections by LDSS, composed of 18 accessions (24.66% of the primary core collection), let more than 94.85% of polymorphic loci remained, 97.55% of the observed number of alleles and 99.28% of the effective number of alleles of the mini core collection, respectively. The Nei’s gene diversity and Shannon’s Information index of core collection were 0.294 and 0.443, respectively. Taken all together, the results indicated that mini core collections constructed by the LDSS strategy represented their primary core collections and provided a rational framework for intensive surveys of natural variation in C. officinalis genetic resources. 相似文献
9.
The wild soybean, an annual self-pollinating plant, is the progenitor of soybeans and is extensively distributed in the Far
East of Russia, the Korea peninsula, China and Japan. Geographically, Japan is surrounded by sea and insulated from China.
We preliminarily evaluate whether the Japanese and Chinese wild soybean germplasm pools are genetically differentiated from
each other using SSR markers. The results showed that the two pools have great genetic differentiation. Some loci presented
obvious differences in mean genetic divergence (GST) value between the two pools. The GST among the geographic regions in China was higher than that in Japan. The average within-geographic region gene diversity
values (HS) in the two pools were completely identical and thus the genetic difference between the two pools was mostly attributed to
the relatively high level of between-geographic region gene diversity (DST) in China. We suggest that Japanese and Chinese wild soybeans should be comparatively independently evolving in phylogeny. 相似文献
10.
Arvindkumar Salunkhe Shubhada Tamhankar Sujata Tetali Maria Zaharieva David Bonnett Richard Trethowan Satish Misra 《Genetic Resources and Crop Evolution》2013,60(1):165-174
Emmer wheat (Triticum dicoccon Schrank) is still largely cultivated in India, and highly appreciated for the preparation of traditional dishes. Moreover, its nutritional characteristics could justify a development of its cultivation. The perspective of genetic improvement however requires a good knowledge of the genetic diversity existing within the eco-geographic group of Indian emmer wheats. A set of 48 emmer wheat accessions from India including 28 from a local collection and 20 Indian accessions obtained from CIMMYT, Mexico, was assessed for genetic variability using 47 microsatellite (SSR) markers, distributed over all the 14 chromosomes. The number of alleles per locus ranged from 2 to 9, with an average of 3.87 alleles per locus. A total of 201 alleles were detected at 52 loci with average polymorphic information content of 0.35 per locus and a mean resolving power of 1. The pair-wise similarity coefficients calculated from binary data matrix based on presence or absence of alleles varied from 0.15 to 0.98, but was greater than 0.5 for most accessions, indicating a high level of similarity. A cluster analysis based on the similarity matrix identified nine distinct accessions and three clusters. All the recently developed commercial varieties were distinctly different from the clusters. Based on the analysis, it appears that Indian emmer wheats are not very diverse. Consequently, there is a need to increase the diversity within the Indian emmer wheat eco-geographic group, by introducing diversity from other eco-geographic groups, or even from other wheat species. 相似文献
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12.
Mohammad R. Sabzalian Aghafakhr Mirlohi Ghodratollah Saeidi Mohammad T. Rabbani 《Genetic Resources and Crop Evolution》2009,56(8):1057-1064
Wild species of safflower, Carthamus oxyacanthus Bieb., is highly crossable with cultivated species, C. tinctorius L. and could be directly exploited in broadening safflower gene pool and improving the crop for biotic and abiotic stress
environments. In this study, genetic diversity among accessions of C. oxyacanthus and their relationships with cultivated safflower were evaluated using agro-morphological traits and polymorphic inter-simple
sequence repeats (ISSR) markers. Significant variation was observed among accessions particularly for seeds per capitulum,
seed yield per plant, harvest index and capitula per plant. Cluster analysis based on agro-morphological traits classified
the wild accessions in two groups according to their geographical regions, and separated them from the cultivated genotypes.
ISSR marker also revealed a high genetic variation among the accessions, and cluster analysis based on this marker divided
genotypes into four groups, with cultivated ones in a separate clade. Genetic variation observed among the wild safflower
germplasm at the DNA level was higher than the agro-morphological traits, indicating that ISSR is an effective marker system
for detecting diversity among safflower genotypes and their genetic relationships. Accessions of C. oxyacanthus with high genetic relationship to cultivated species could be used for interspecific hybridization in breeding programs of
safflower. 相似文献
13.
Alireza Pour-Aboughadareh Mostafa Mahmoudi Mohammad Moghaddam Jafar Ahmadi Ali Ashraf Mehrabi Seyed Siamak Alavikia 《Genetic Resources and Crop Evolution》2017,64(3):545-556
Genetic erosion in cultivated wheat provides a good reason for studying genetic diversity in crop wild relatives. In the present study, genetic diversity of 32 accessions belonging to T. boeoticum species collected from different parts of Iran were evaluated using 13 morphological traits as well as ten inter-simple sequence repeat primers. Statistical analysis for morphological traits showed significant differences among accessions (except number of fertile tillers and total tillers per plant). In principal component analysis, the first three PCA showed 82.65 % of the total morphological variation. Based on the morphological traits, accessions were separated into two main groups by cluster analysis. In molecular analysis, polymerase chain reactions amplified 105 DNA fragments, out of which, 95 (90.47 %) were polymorphic. From geographic perspective, the accessions sampled from western and southwestern of Iran showed the highest and lowest polymorphism, respectively. However, the maximum values of effective number of alleles (Ne), Nei’s gene diversity (He) and Shannon’s information index (I) was related to accessions collected from NW regions. Also, according to cluster analysis and PCoA plot genetic diversity was not related to geographical distribution. Overall, our results revealed a remarkable level of genetic diversity among studied Iranian T. boeoticum accessions; especially accessions collected from Kermanshah and Lorestan provinces, which can be of interest for future breeding programs. So, conservation of germplasm of these areas is recommended. 相似文献
14.
Toan Duc Pham Tri Minh Bui Gun Werlemark Tuyen Cach Bui Arnulf Merker Anders S. Carlsson 《Genetic Resources and Crop Evolution》2009,56(5):679-690
Sesame (Sesamum indicum L.) is a traditional oil crop cultivated throughout South East Asia. To estimate the genetic diversity of this crop in parts
at the region, 22 sesame accessions collected in Vietnam and Cambodia were analyzed using 10 RAPD markers. The 10 primers
generated 107 amplification products of which 88 were polymorphic fragments (83%). Genetic diversity of all populations was
Ht = 0.34 when estimated by Nei’s genetic diversity and species diversity was H′sp = 0.513 when estimated by Shannon diversity index. Genetic distance ranged from 0.03 to 0.43, with a mean genetic distance
of 0.23. The unweighted pair group method with arithmetic averages (UPGMA) cluster analysis for the 22 accessions divided
the material in four groups. The dendrogram revealed a clear division among the sesame accessions based on their geographical
region. Interestingly, some geographically distant accessions clustered in the same group, which might indicate the human
factor involved in the spreading of sesame varieties. The high level of polymorphism shown suggests that RAPD techniques can
also be useful for the selection of parents in sesame (Sesamum indicum L.) breeding program and for cultivar differentiation. 相似文献
15.
Guar [Cyamopsis tetragonoloba (L.) Taub.] is an important commercial crop of India, mainly cultivated in the northwestern part and neighboring areas of Pakistan. High morphological diversity is reported in guar. The present study attempts to analyze the genetic diversity in cultivated guar using allozyme polymorphism and compare it with reported morphological diversity. Accessions for the study were selected from a set of guar germplasm conserved at the National Bureau of Plant Genetic Resources, New Delhi. The morphological data of 108 selected accessions was subjected to UPGMA clustering. Fifty-five accessions were then picked randomly from the clusters generated. Tris-borate system (pH 8.3) was found to be most effective for detection of allozyme polymorphism in guar. Ten enzymes were selected for the study out of 18 systems tried, namely, malate dehydrogenase, malic enzyme, phosphogluco isomerase, glutamate oxaloacetate transaminase, esterase, peroxidase, alcohol dehydrogenase, glutamate dehydrogenase, glucose 6-phosphate dehydrogenase and shikimate dehydrogenase. A total of 20 loci were detected with 34 alleles. The number of polymorphic loci in different accessions was observed to be highly variable (0–9). An average of 1.27 allozyme per polymorphic locus was observed. The allele frequency data of the 55 accessions was used to determine genetic diversity parameters. The dendrogram generated on genetic distance showed three clusters in the distance range of 0–0.28. Most of the accessions were in the first clusters in a narrow distance range of 0–0.08. The second cluster consisted of improved varieties and accession from Pakistan. The third cluster of accessions was genetically more distant but there was no definite segregation of accessions according to the place of collection. The accessions from south west Rajasthan were scattered in all the three clusters showing higher variability in this region, also supported by higher morphological variation. The genetic distance was low among accessions of guar, indicating low diversity in India. 相似文献
16.
Milene Silvestrini Michele G. Junqueira Andréa C. Favarin Oliveiro Guerreiro-Filho Mirian P. Maluf Maria B. Silvarolla Carlos A. Colombo 《Genetic Resources and Crop Evolution》2007,54(6):1367-1379
Genetic diversity among 115 coffee accessions from the Coffea Germplasm Collection of IAC was assessed using SSR markers. The germplasm represents 73 accessions of Coffea arabica derived from spontaneous and subspontaneous plants in Ethiopia and Eritrea, species center of origin and diversity, 13 commercial
cultivars of C. arabica developed by the Breeding Program of IAC, 1 accession of C. arabica cv. ‘Geisha’, 13 accessions of C. arabica from Yemen, 5 accessions of C. eugenioides, 4 accessions of C. racemosa and 6 accessions of C. canephora. Genetic analysis was performed using average number of alleles per locus (A), proportion of polymorphic loci (P), Shannon’s genetic index (H′ and G′ST) and clustering analysis. All evaluated species were distinguished by a cluster analysis based on Jaccard’s coefficient.
Differentiation between the cultivated plants of C. arabica and accessions derived from spontaneous and subspontaneous plants was observed. Spontaneous and subspontaneous accessions
from Ethiopia were separated according to the geographical origin: east and west of the Great Rift Valley. Cultivated plants
showed a low genetic diversity with a division in two groups: accessions from Yemen (H′=0,028) and Brazilian commercial cultivars (H′=0,030). The results agreed with previously reported narrow genetic basis of cultivated plants of C. arabica and supported the hypotheses about domestication of the species. This study also showed a significant genetic diversity among
accessions from Ethiopia and Eritrea present in the Germplasm Collection of IAC. This diversity is specially observed in accessions
from Sidamo (H′=0,143), Kaffa (H′=0,142) and Illubabor (H′=0,147) indicating their importance as source of genetic variability for coffee breeding programs. 相似文献
17.
Marc Moragues Marian Moralejo Mark E. Sorrells Conxita Royo 《Genetic Resources and Crop Evolution》2007,54(5):1133-1144
A comprehensive characterization of crop germplasm is critical to the optimal improvement of the quality and productivity
of crops. Genetic relationships and variability were evaluated among 63 durum wheat landraces from the Mediterranean basin
using amplified fragment length polymorphisms (AFLPs) and microsatellites markers. The genetic diversity indices found were
comparable to those of other crop species, with average polymorphism information content (PIC) values of 0.24 and 0.70 for
AFLP and microsatellites, respectively. The mean number of alleles observed for the microsatellites loci was 9.15. Non-metric
multi-dimensional scaling clustered the accessions according to their geographical origin with the landraces from the South
shore of the Mediterranean Sea closely related. The results support two dispersal patterns of durum wheat in the Mediterranean
basin, one through its north side and a second one through its south side. 相似文献
18.
B. J. Stodart H. Raman N. Coombes M. Mackay 《Genetic Resources and Crop Evolution》2007,54(4):759-766
Bread wheat (Triticum aestivum L.) landraces held within ex situ collections offer a valuable and largely unexplored genetic resource for wheat improvement
programs. To maximise full utilisation of such collections the evaluation of landrace accessions for traits of interest is
required. In this study, 250 accessions from 21 countries were screened sequentially for tolerance to aluminium (Al) using
haematoxylin staining of root tips and by root regrowth measurement. The staining test indicated tolerance in 35 accessions,
with an intermediate response to Al exhibited in a further 21 accessions. Of the 35 accessions classified as tolerant, 33
also exhibited increased root length following exposure to Al. The tolerant genotypes originated from Bulgaria, Croatia, India,
Italy, Nepal, Spain, Tunisia, and Turkey. AFLP analysis of the 35 tolerant accessions indicated that these represent diverse
genetic backgrounds. These accessions form a valuable set of germplasm for the study of Al tolerance and may be of benefit
to breeding programs for expanding the diversity of the gene pool from which tolerant cultivars are developed. 相似文献
19.
Yu-Xia Yang Wei Wu You-Liang Zheng Li Chen Ren-Jian Liu Chun-Yan Huang 《Genetic Resources and Crop Evolution》2007,54(5):1043-1051
Genetic diversity and relationships among 48 safflower accessions were evaluated using 22 inter-simple sequence repeats (ISSR)
primers. A total of 429 bands were amplified, and 355 bands (about 82.7%) were polymorphic. Five to forty-one polymorphic
bands could be amplified by each primer, with an average of 16.1 polymorphic bands per primer. The results showed that the
polymorphism of the safflower germplasm was higher at the DNA level. All the 48 accessions could be distinguished by ISSR
markers and were divided into 9 groups based on ISSR GS by using UPGMA method. The genetic relationships among the accessions
from different continents were closer. Comparatively, the genetic diversity of the accessions originated from Asia was higher,
from Europe assembled. The results also showed that the genetic variation of accessions from Indian and Middle Eastern safflower
diversity centers were relatively higher. ISSR is an effective and promising marker system for detecting genetic diversity
among safflower and give some useful information on its phylogenic relationships. 相似文献
20.
Wild melon diversity in India (Punjab State) 总被引:1,自引:1,他引:0
Anamika Roy S. S. Bal M. Fergany Sukhjeet Kaur Hira Singh Ajaz A. Malik Jugpreet Singh A. J. Monforte N. P. S. Dhillon 《Genetic Resources and Crop Evolution》2012,59(5):755-767
We present here the first comprehensive genetic characterization of wild melon accessions from northern India. The genetic diversity among 43 wild melon accessions collected from the six agro-ecological regions of the Punjab State of India was assessed by measuring variation at 16 Simple Sequence Repeat (SSR) loci, morphological traits of plant habit and fruit morphological traits, two yield-associated traits, root nematode resistance and biochemical composition (ascorbic acid, carotenoids, titrable acidity). Variation among accessions was observed in plant habit and fruit traits and wild melon germplasm with high acidity and elevated carotenoid content and possessing resistance to Meloidogyne incognita was identified in the collection. A high level of genetic variability in wild melon germplasm was suggested by SSR analysis. Comparative analysis using SSRs of the genetic variability between wild melons from the north and other melons from the south and east regions of India and also reference accessions of cultivated melon from Spain, Japan, Korea, Maldives, Iraq and Israel, showed regional differentiation among Indian melon accessions and that Indian germplasm was not closely related to melon accessions from other parts of the world. A highly drought tolerant accession belonging to var. agrestis Naud. was also identified. 相似文献