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1.
Mohammad Jaffar Aghaei Javad Mozafari Ali Reza Taleei Mohammad Reza Naghavi Mansoor Omidi 《Genetic Resources and Crop Evolution》2008,55(3):341-349
The wide morphological variation of Aegilops tauschii has led to the distinction of different subspecies; a typical ssp. tauschii and a second ssp. strangulata. However some researchers pointed out the existance of the intermediate form among morphologically distinguished subspecies.
Distribution, diversity and the relationship between different subspecies and the intermediate form were evaluated in the
Iranian Ae. tauschii collection. This collection was classified to 15 different populations according to morphological similarities and the collecting
origin of accessions. The highest variation was found in tauschii population of Golestan followed by tauschii populations of Gilan and Ardebill, whereas the lowest variation was observed in tauschii populations of central Iran. Two discriminant functions suggested that the length of rachis node and spikelet glume, particularly,
the length/width ratios of these traits had the highest impact on identification of different forms. Mahalanobis distances
(D
2
) between the two subspecies along with intermediate form on the multidimensional scaling plot showed that the intermediate
form is more similar to ssp. tauschii than ssp. strangulata. Although, the diversity within the ssp. strangulata was not very high, it widely affected the diversity of Iranian accessions of Ae. tauschii through continues crossing with the more diversed subspecies, tauschii, during thousands of years. This fact had lead to expansion of its distribution from its origin to Northern Khorasan, Northern
Semnan and Eastern Ardebill by producing the intermediate form. 相似文献
2.
Hojjatollah Saeidi Badradin Ebrahim Sayed Tabatabaei Mehdi Rahimmalek Majid Talebi-Badaf Mohammad Reza Rahiminejad 《Genetic Resources and Crop Evolution》2008,55(8):1231-1238
The diploid goatgrass Aegilops
tauschii is considered the D-genome donor of bread wheat and has probably a centre of diversity in north of Iran. In order to measure
the genetic diversity of and the relationships among different populations, varieties and subspecies belonging to Ae. tauschii in Iran, DNA was extracted from 48 accessions of Ae. tauschii collected across the geographic range of the species in the Country and the genetic diversity was assessed using AFLPs based
on eight PstI/MseI +3 primer pairs resulted in 277 bands, 198 of which were polymorphic. High level polymorphism was detected, with an average
of polymorphism rate of 0.715; relatively low genetic similarity (0.455) between accessions and significant difference between
the lowest (0.179) and the highest genetic similarity (0.817). The Iranian Ae. tauschii populations showed high level of genetic diversity. The populations studied were divided into two groups: one group was mainly
representing Northern populations collected from Southern Caspian Sea shore and the other group was mainly representing Northeast
and Northwest populations. Based on the results of this study, it can be suggested that Ae. tauschii possesses two separate gene-pools in Iran: Northern and Northeastern–Northwestern. Considering the needs for introducing
new characteristics and alleles for wheat improvement purposes, Ae. tauschii Iranian gene-pool is assumed to be of high importance for more investigation in the future. 相似文献
3.
Mohammad Reza Naghavi Mariam Hajikram Ali Reza Taleei Mohammad Jafar Aghaei 《Genetic Resources and Crop Evolution》2010,57(3):423-430
Genetic diversity and population genetic structure of Aegilops tauschii in Northern Iran were studied based on nine microsatellite loci. A high level of genetic diversity was observed from the
accessions collected from six regions (provinces). These accessions include 79 samples of the two subspecies (tauschii and strangulata), the intermediate form (among morphologically distinguished subspecies) and ten accessions of Triticum aestivum. The nine microsatellites revealed a total of 141 alleles, with an average of 15.7 alleles per locus. A comparison of the
parameters showing genetic diversity, including the observed heterozygosity (Ho), gene diversity (He) and Shannon’s information index (I) of Ae. tauschii accessions from different provinces in Northern Iran, indicated that subsp. tauschii possesses the highest genetic diversity, followed by intermediate form. Genetic distance between subsp. strangulata and subsp. tauschii was low, confirming high gene flow between these two subspecies. However, intermediate form was more distinct from both of
them. It was also found that the genetic diversity of T. aestivum is obviously lower than that of Ae. tauschii accessions. Moreover, the level of genetic diversity for Gilan, Golestan and Mazanderan provinces was higher than for Ardebil,
Ghazvin and Semnan provinces, suggesting that these regions may provide a readily available source of potentially useful variation
for wheat improvement. 相似文献
4.
All the 79 Aegilops tauschii Coss. accessions of Iranian origin from Prof. Kihara’s collection were analyzed electrophoretically. Of 23 enzyme-encoding
loci studied, 11 were polymorphic. In Iran Ae. tauschii is presented by ssp. tauschii and ssp. strangulata which distinctly differ genetically, morphologically and ecologically. Variation patterns of low polymorphic locus Aco2 and highly polymorphic Ep are similar in both subspecies. In contrast, variation of Acph1, Ak, Est2, Est5, Got1, Got2, Got3 and Lap is a set of diverse patterns which markedly differ between subspecies and natural regions also, implying that natural selection
is involved. 相似文献
5.
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
6.
Genetic diversity was investigated in 73 accessions of emmer wheat (Triticum dicoccon Schrank) from 11 geographical regions using a set of 29 simple-sequence repeat (SSR or microsatellite) markers, representing
at least two markers for each chromosome. The SSR primers amplified a total of 357 different alleles with an average of 12.31
alleles per locus. The number of fragments detected by each primer ranged between 6 (Xgwm1066) and 21 (Xgwm268). Null alleles were detected in nine of the 29 primers used. A high level of gene diversity index was observed. Across the
29 primers, gene diversity ranged from 0.60 (Xgwm46) to 0.94 (Xgwm655), with a mean of 0.82. There was a highly significant correlation (r=0.882; p<0.01) between gene diversity index and the number of loci, showing the number of loci per se is a strong indicator of diversity. Analysis of genetic diversity within and among eleven geographical regions revealed most
of the genetic diversity of the total sample resided within regions. The coefficient of gene differentiation (Gst = 0.27)
showed that the genetic variation within and among the 11 geographical regions was 73 and 27%, respectively. High value of
mean number of alleles per locus was found in Iran (4.86) followed by Morocco (4.10) and Armenia (4.03). On the contrary,
lower mean number of alleles per locus was detected in Yemen (2.83). The average gene diversity index across regions ranged
from 0.52 (Slovakia) to 0.67 (Morocco) with an average of 0.60. Multivariate techniques of principal component analysis and
clustering were employed to examine genetic relationship among the 73 emmer wheat accessions vis-à-vis geographical regions
of collections. The genetic distance coefficients for all possible 55 pairs of regional comparisons ranged from 0.63 (between
Iran and Armenia, Georgia and Azerbaijan, Georgia and Slovakia) to 0.97 (between Morocco and Yemen, Spain and Georgia, and
Turkey and Iran) with a mean of 0.82. From the PCA results, a two dimensional plot of PC1 versus PC2 was constructed. The
scatter plot of the first two principal components which explained altogether 27% of the total variation depicted the presence
of a clear pattern of geographical differentiation except in few cases like accessions from Caucasian region. Similar pattern
of genetic relationships among accessions was observed in cluster analysis. The study provided genetic information of emmer
wheat in relation to geographical regions of origin. The information could be utilized in crop improvement, germplasm conservation
programs, and in further investigation. 相似文献
7.
Shinsuke Yamanaka Ikuo Nakamura Hirokazu Nakai Yo-Ichiro Sato 《Genetic Resources and Crop Evolution》2003,50(5):529-538
The direct ancestor of rice (Oryza sativa L.) is believed to be AA genome wild relatives of rice in Asia. However, the AA genome wild relatives involve both annual and perennial forms. The distribution of the retrotransposon p-SINE1-r2, a short interspersed nuclear element (SINE) at the waxy locus was analyzed in diverse accessions of the AA genome wild relatives of rice (O. rufipogon sensu lato). Most annual wild rice accessions had this retrotransposon, while most perennial types lacked this element, contradicting results to the previous studies. Results presented here suggest that O. sativa has dual origin that lead to indica-japonica differentiation. Results suggest the indica line of rice varieties evolved from the annual genepool of AA genome and the japonica varieties from the perennial genepool of AA genome wild rice. 相似文献
8.
Cahill P. Joseph 《Genetic Resources and Crop Evolution》2004,51(7):773-781
Chia, Salvia hispanica L., was a staple crop in pre-Columbian Mesoamerica. Despite the great potential of the species as an oilseed crop, little research related to domesticated and wild varieties exists. A study was undertaken to assess genetic diversity among 38 wild and domesticated accessions of S. hispanica collected throughout Mesoamerica by using RAPD markers. Genetic diversity was higher among wild varieties (H
G= 0.15) than all domesticated varieties (H
G= 0.10) and modern commercial domesticated varieties (H
G= 0.02), suggesting a slight loss of diversity accompanying domestication and a near lack of diversity in modern commercial varieties. In addition, the preliminary results indicate that the center of genetic diversity is in the highlands of western Mexico. 相似文献
9.
Hironori Katayama Shiho Adachi Toshiya Yamamoto Chiyomi Uematsu 《Genetic Resources and Crop Evolution》2007,54(7):1573-1585
Iwateyamanashi (Pyrus ussuriensis var. aromatica) is one of the Pyrus species which grows wild in Japan. The number of Iwateyamanashi trees has been decreasing, so conservation and evaluation
is urgently needed. Over 500 accessions of Pyrus species collected from Iwate in northern Tohoku region are maintained at Kobe University as an Iwateyamanashi germplasm collection.
In order to investigate the genetic diversity, five SSR (simple sequence repeat) markers, developed from Japanese and European
pear were examined for 86 Pyrus individuals including 58 accessions from Iwate. These SSR loci could discriminate between all the Iwate accessions except
for 10 that bear seedless fruit, as well as determine the genetic diversity in Iwateyamanashi germplasms. High levels of variation
were detected in 41 alleles and the mean observed heterozygosity across 5 loci was 0.50 for the Iwate accessions. Seedless
accessions sharing identical SSR genotype with the local pear variety “Iwatetanenashi” were supposed to have been propagated
vegetatively via grafting. In an UPGMA phenogram, Japanese pear varieties (P. pyrifolia) were clustered into two groups with some Iwate accessions including seedless ones. Another 38 Iwate accessions were not
clustered clearly, and there was no clear relationship between these accessions and geographical distribution or morphological
characters. Allele frequency revealed that the Iwate accessions were genetically more divergent than the Japanese pear varieties.
Most Japanese pears possessed a 219 bp deletion at a spacer region between the accD and psaI genes in the chloroplast DNA (cpDNA), but other Pyrus species and two Iwateyamanashi trees did not. In the Iwate accessions, 79.3% had a deletion type cpDNA and others had a standard
type cpDNA without deletion. These results are indicative of the wide range of genetic diversity in the Iwate accessions which
include Japanese pear varieties. A combination of SSR and cpDNA analyses revealed high heterogeneity in Iwateyamanashi and
coexistence of Iwateyamanashi and hybrid progeny with P. pyrifolia. These could be reasons for the wide range of continuous morphological variation described previously. 相似文献
10.
Mkabwa L. K. Manoko Ronald G. van den Berg Richard M. C. Feron Gerard M. van der Weerden Celestina Mariani 《Genetic Resources and Crop Evolution》2008,55(3):409-418
Two hexaploid species of Solanum sect. Solanum are present in Africa: Solanum scabrum and S. nigrum. Solanum scabrum is a widely cultivated species and is used as a leafy vegetable, as a source of medicine and as a source of ink dye. In previous
studies a wide range of morphological diversity has been reported in this species and in some studies subspecies have been
proposed. Subspecies are also recognized in S. nigrum. However, it has not been established whether or not the morphological differences are reflected at the genomic level. The
present study applies AFLPs to study the genetic diversity in S. scabrum and its relationship to geographical provenance, morphological differences and the possible existence of subspecies within
S. scabrum and S. nigrum. The data obtained were analyzed with cluster analysis (using UPGMA and NJ). The results indicate that the genetic variation
within S. scabrum was higher within accessions than between accessions. Accessions did not cluster according to their geographical provenance,
indicating that accessions from different geographical areas were not significantly different genetically. The clustering
reflected neither morphological differences nor domestication status (cultivated or wild). The morphological differences exhibited
by S. scabrum could be due to selection by farmers for different plant types. The AFLP derived clustering pattern did not segregate the
subspecies recognized in S. scabrum and S. nigrum into separate subclusters. 相似文献
11.
Triticum tauschii (Coss.) Schmalh. (Aegilops squarrosa auct. non L., 2n=2x=14, DD genome) with its diverse range of accessions and distribution provides a unique opportunity for exploiting novel genetic variability for wheat (T. aestivum L.) improvement associated with biotic/abiotic stress factors. From our working collection of 490 T. tauschii accessions we have so far produced 430 different synthetic hexaploids (2n=6x=42, AABBDD) resulting from the chromosome doubling of Triticum turgidum L. s. lat. x T. tauschii F1 hybrids (each synthetic involving a different T. tauschii accession). We present here our results on hybrid production, plantlet regeneration, cytology, colchicine induced doubling of the 2n=3x=21 chromosome F1 hybrids, seed increase of the doubled progeny and screening for a biotic stress; Cochliobolus sativus Ito and Kuribay (syn. Helminthosporium sativum Pamm. King and Bakke); of 250 of these synthetic hexaploid (2n=6x=42) amphiploids. Application of the direct crossing methodology involving susceptible T. aestivum cultivars with resistant T. tauschii accessions is also alluded to. 相似文献
12.
Sheji Mary N. V. Nair Pankaj Kumar Chaturvedi A. Selvi 《Genetic Resources and Crop Evolution》2006,53(6):1221-1231
Saccharum spontaneum L. a wild relative of sugarcane is the most variable and diverse among the Saccharum species. This species had been successfully exploited in sugarcane improvement programmes since 1915 and most of the present day commercial varieties are derivatives of interspecific hybrids involving S. spontaneum. The S. spontaneum germplasm available today in the World collections is diverse and represent different geographical groups. In the present investigation, an attempt was made to characterize 40 S. spontaneum clones collected from 4 different geographical areas in India using 20 random, 2 ISSR and 2 telomere primers. Of the 491 bands generated by these primers 83.9% were polymorphic. The genetic diversity estimated based on these markers was found to be moderate (48.9%). The pair-wise genetic distance between the accessions ranged from 29.8 to 60.0. The accessions from Arunachal Pradesh were found to be the most diverse, while Tamil Nadu accessions showed relatively less diversity. Diversity between Tamil Nadu and Kerala collections was found to be low, while the diversity between the Orissa group and the rest was found to be high. The collections from Mayurbanj and Cuttack regions of Orissa were found to be distinct. Arunachal Pradesh accessions, being more diverse, are a potential source for exploitation in sugarcane breeding programmes. 相似文献
13.
14.
M. R. Naghavi M. J. Aghaei A. R. Taleei M. Omidi J. Mozafari M. E. Hassani 《Genetic Resources and Crop Evolution》2009,56(4):499-506
Simple sequence repeats (SSRs), highly dispersed nucleotide sequences in genomes, were used for germplasm analysis and estimation
of the genetic relationship of the D-genome among 52 accessions of T. aestivum (AABBDD), Ae. tauschii (DtDt), Ae. cylindrica (CCDcDc) and Ae. crassa (MMDcr1Dcr1), collected from 13 different sites in Iran. A set of 21 microsatellite primers, from various locations on the seven D-genome
chromosomes, revealed a high level of polymorphism. A total of 273 alleles were detected across all four species and the number
of alleles per each microsatellite marker varied from 3 to 27. The highest genetic diversity occurred in Ae. tauschii followed by Ae. crassa, and the genetic distance was the smallest between Ae. tauschii and Ae. cylindrica. Data obtained in this study supports the view that genetic variability in the D-genome of hexaploid wheat is less than in
Ae. tauschii. The highest number of unique alleles was observed within Ae. crassa accessions, indicating this species as a great potential source of novel genes for bread wheat improvement. Knowledge of
genetic diversity in Aegilops species provides different levels of information which is important in the management of germplasm resources. 相似文献
15.
S. Imazio M. Labra F. Grassi A. Scienza O. Failla 《Genetic Resources and Crop Evolution》2006,53(5):1003-1011
The origin of the grapevine, Vitis vinifera ssp . sativa L., has been investigated with archaeobotanical–archaeological, cultural and historical data indicating a unique domestication
centre located in the Caucasian and Middel-East regions about 6–7000 years ago, but, events leading to the domestication of
this species are still an open issue. In this work, eight universal chloroplast microsatellites are used to assess genetic
relationships among varieties selected as representatives of four distinct geographical groups from Middle-East to Western
European regions. Results show that two out of the eight analysed chloroplast loci are polymorphic within the 142 individuals. Allele variants of the cpSSR loci combine in a total of six different haplotypes. The analysis of haplotypes distribution and haplotype diversity (HD) suggest that only three out of the six haplotypes are represented in the Caucasian and Middle-East samples, with 90% of
individuals sharing the same haplotype. Moreover, the presence of all six haplotypes in the European accessions, with a high
level of haplotype diversity, suggests varietal influx in these areas. Concerning the Western European varieties, especially
in Spanish accessions, half of the individuals share haplotype VI which is completely absent in the Caucasian and Middle-East
cultivars. This result opens the discussion about the existence of a unique and common domestication centre, located in the
Caucasian and Middle-East area, for all the European cultivars.
This work suggests the usefulness of chloroplast genome markers to provide information on haplotype distributions that could
help to identify further geographical areas for grapevine varietal evolution. 相似文献
16.
María Ferriol Maria Belén Picó Fernando Nuez 《Genetic Resources and Crop Evolution》2003,50(3):227-238
Increasing the knowledge of the molecular diversity of a crop is essential for extending its genetic base, identifying cultivars and selecting parental varieties for breeding programs. In this sense, Cucurbita maxima Duch. is poorly characterised. Nineteen accessions of this species and 8 related Cucurbita accessions were included in a genetic diversity analysis. For this purpose, Random Amplified Polymorphic DNA markers (RAPDs), which analyse neutral variability, and Sequence-Based Amplified Polymorphism (SBAPs), which preferentially amplify coding regions of the genome, were used. While the UPGMA cluster and the principal coordinates analysis obtained using RAPDs did not group the different accessions according either to fruit morphological criteria or to passport data (origin and agro-climatic conditions), the principal coordinates analysis obtained using SBAPs grouped the different pumpkin accessions fundamentally according to the type of use (human consumption, animal fodder or ornamental). This passport trait is reported to be associated with agronomic breeding characters of interest. The usefulness of both types of markers for discriminating accessions of breeding interest is discussed. 相似文献
17.
S. Uma S. A. Siva M. S. Saraswathi M. Manickavasagam P. Durai R. Selvarajan S. Sathiamoorthy 《Genetic Resources and Crop Evolution》2006,53(2):349-355
Sixteen collections of the wild Musa species, Musa balbisiana Colla collected from different regions of India were studied for their intraspecific relationships using random amplified
polymorphic DNA (RAPD) markers. Out of 80 primers screened, 34 primers produced reproducible bands and four primers among
them showing polymorphic bands were used. In all, 43 DNA fragments were amplified averaging 10.75 per primer. Of these, 31
amplified fragments showed polymorphism (averaging of 7.75 per primer). The extent of polymorphism (74.6%) has indicated the
existence of considerable variation at the DNA level within the species. The 16 accessions were clustered into four as against
seven clusters obtained through morphotaxonomic characterization. The inter relationships based on geographical origin in
comparison with molecular characterization have been discussed. 相似文献
18.
Zahra Tahernezhad Zeyn-alabedin Musavi Mohammad Javad Zamani Mohammad Jafar Aghaei Bahram Rostam Foroudi 《Genetic Resources and Crop Evolution》2013,60(3):905-911
Variation of high molecular weight glutenin subunits (HMW-GS) in 28 Iranian Aegilops tauschii (2n = 2x = 14, DD) accessions studied by sodium dodecyl sulphate electrophoresis method (SDS-PAGE). The results showed high variation of HMW-GS in the accessions. The range of frequency in 14 HMW-GS combinations was 3.57–25 % in the accessions. AMOVA showed the molecular variance between the geographic areas was lower than within the geographic areas. According to Nei’s genetic diversity, the highest diversity levels were in Semnan, Golestan and Azarbayjan, on the other hand the lowest levels of diversity were found in Khorasan, Gilan and Mazandaran accessions. Hence, the Caspian Sea South East accessions also Azerbayjan in Iran have more diversity. AMOVA did not show variance between strangulata and tauschii but there was more genetic diversity in ssp. tauschii subspecies in comparison of ssp. strangulata according to Nei’s gene diversity and Shannon information index. It showed Iranian Ae. tauschii have a good potential for bread making quality improvement in bread wheat. 相似文献
19.
Dengcai Liu Lianquan Zhang Zehong Yan Xiujin Lan Youliang Zheng 《Genetic Resources and Crop Evolution》2010,57(3):325-328
Aegilops tauschii Coss., the D-genome progenitor of common wheat (Triticum aestivum L.) includes two subspecies, tauschii and strangulata (Eig) Tzvel. Subspecies tauschii has a wide geographic distribution spreading westwards to Turkey and eastwards to Afghanistan and China, while ssp. strangulata has a narrower distribution occurring only in two disjoined regions, southeastern Caspian Iran and Transcaucasia. A collection
of 56 Ae. tauschii accessions was screened at adult stage against a mixture of pathotypes of stripe rust prevalent in the current wheat production
in China. The results for three crop seasons indicated that among the 38 ssp. tauschii accessions, 37 were susceptible and only one was resistant, while all the 18 ssp. strangulata accessions were resistant. These results indicated that stripe rust resistance was related to taxonomic origin. Further genetic
analysis revealed the resistance of stripe rust in ssp. strangulata accession AS2388 was conferred by a single dominant gene. 相似文献
20.
Multivariate analysis of genetic variation in Aegilops tauschii from the world germplasm collection 总被引:2,自引:0,他引:2
Alexander Ju. Dudnikov 《Genetic Resources and Crop Evolution》2000,47(2):185-190
A study of Aegilops tauschii subspecies constitution was undertaken. The data on allozyme and morphologic variation among 308 plants from 154 accessions were used for multivariate analysis. ACPH1 and (glume width)/(rachis segment width) ratio were found to be reliable criteria to distinguish between sspp. tauschii and strangulata. 相似文献