共查询到20条相似文献,搜索用时 62 毫秒
1.
Pear (Pyrus Species) Genetic Resources in Iwate, Japan 总被引:1,自引:0,他引:1
Iwateyamanashi (Pyrus ussuriensis Maxim. var. aromatica (Nakai et Kikuchi) Rehd.) is one of the Pyrus species grown wild in Japan. The origin of the Japanese pear (P. pyrifolia) is uncertain but it has been suggested that Iwateyamanashi is the possible progenitor of the modern Japanese cultivar. During
the last few decades, the number of Iwateyamanashi trees has been decreasing and therefore, conservation is urgently needed.
After 13 explorations in the northern Tohoku region of Japan, 615 pear trees and 30 local names were recognized mainly in
Iwate Prefecture. The center of the distribution seemed to be somewhere around Mt. Hayachine to the northern area of Kitakami
highlands (from lat. 39 °20′ to 40 °10′N, and from long. 141 °20′ to 141 °50′E). Four morphological characters concerning
fruit shape, measured for 85 trees, showed a wide range of continuous variation. For the skin colour of fruit, 51% of trees
bore russet type fruits, 22% smooth and 27% intermediate ones. Most of the fruits had five loculi but Sanenashi fruits (seedless
pear), one of the old cultivars, had three, and fruits of another two trees had four. More than 80% of trees tended to produce
fruits with a calyx but some trees bore fruits without a calyx. These observations indicate a wide range of genetic diversity
in Pyrus species which is caused, not only by high heterogeneity in Iwateyamanashi itself, but also by the coexistence of Iwateyamanashi,
P. pyrifolia (Burm.) Nakai and hybrid progeny in this area. Already 250 trees have been conserved as genetic resources by grafting at
Kobe University. 相似文献
2.
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
3.
Gunter Backes Jihad Orabi Asmelash Wolday Amor Yahyaoui Ahmed Jahoor 《Genetic Resources and Crop Evolution》2009,56(1):85-97
Remarkable morphological variation has been found within small Eritrean barley fields. Barley was collected from fields approximately
50 m2 in size. Spike shape, type, and colour were observed to vary both between and within fields. A set of 39 Simple Sequence
Repeats (SSR) markers were used to explore the genetic diversity of the Eritrean barley collected from small-scale farmer’s
fields. Significant genetic diversity was found within the barley fields. Out of 240 spikes collected from 24 fields (10 spikes
per field), only two spikes from geographically distant fields were genetically similar. Based on the SSR data, individual
farmers’ fields were found to possess 97.3% of the genetic variation present in the Eritrean barley. We discuss a strategy
to improve the barley yield in Eritrea, and to facilitate the in situ conservation of barley genetic diversity.
Gunter Backes and Jihad Orabi contributed equally to this work. 相似文献
4.
Mauricio Parra-Quijano Sauris Panda Nohra Rodríguez Elena Torres 《Genetic Resources and Crop Evolution》2012,59(1):49-66
Ullucus tuberosus (common name ‘ulluco’) is a popular tuber crop of Andean highlands. Until now attention has been focused on ulluco from Bolivia,
Peru and Ecuador, but little is known about its diversity in Colombia. Thirty-six accessions of cultivated ulluco preserved
in the Gene Bank of the Universidad Nacional de Colombia were studied to assess the genetic diversity and spatial genetic
structure of Colombian ulluco. We used morphological characters, molecular markers (total proteins, isozymes and RAPDs) and
ploidy level. High morphological variability, especially for tuber shape and colour characters, was found. Eight accessions
from north-east Colombian Andes showed some typical character-states of wild ulluco, suggesting that they could be partially
domesticated forms. Genetic analysis using RAPD markers indicated that these accessions were very similar to other cultivated
ullucos belonging to the same region. The regional structure observed in isozyme and RAPD dendrograms was confirmed by AMOVA
results (52.6% among-region variation) and the spatial correlogram, showing the presence of two gene pools of ulluco in Colombia.
Our results and the accumulated data suggest that ulluco was introduced to Colombia at least two times. Initially, semi-domesticated
forms would have come from the central Andes to north-east Colombian Andes, where the native inhabitants would have completed
the domestication process. Again, fully domesticated ullucos might have been introduced to south-west Colombian Andes. 相似文献
5.
6.
7.
Axel Diederichsen 《Genetic Resources and Crop Evolution》2008,55(3):419-440
A characterization of 10,105 accessions of hexaploid cultivated oat (Avena sativa L. sensu lato) from 85 countries of the Plant Gene Resources of Canada (PGRC) collection was conducted at Saskatoon, Saskatchewan,
Canada. Eight environmentally stable morphological characters (panicle type, panicle erectness, panicle density, lemma colour,
dorsal awn of lemma, ligula, major infraspecific group), differentiated into 18 character states, were used to define genetically
distinct morphological groups. Comparisons of oat diversity from different countries, among the major infraspecific groups
and among Canadian oat cultivars registered between 1886 and 2002 were possible. The 10,105 accessions represented 118 different
morphological groups. The number of accessions in each morphological group was unevenly distributed with the 13 most frequent
morphological groups including 90% of the accessions. The most frequent morphological groups in the PGRC collection were identical
with the most frequent types of Canadian oat cultivars. The greatest richness of diversity was found in oat from countries
with temperate climates and intensive oat breeding programmes. The oat accessions comprised 8,754 accessions of common hulled
oat, 183 accessions of hull-less oat and 1,168 accessions of red oat. For red oat (A. byzantina C. Koch), West Asia was richest in diversity. The USA could be considered a secondary centre of diversity for red oat and
Canada a secondary centre of diversity for hull-less oat. Morphological diversity of oat cultivars released in Canada increased
during the twentieth century. The morphological groups were related to formal taxonomical infraspecific classifications of
A. sativa. Applications of the concept of defining morphological groups for phenotyping a large germplasm collection are demonstrated
discussed. 相似文献
8.
Giuseppina Logozzo Rosa Donnoli Leonardo Macaluso Roberto Papa Helmut Knüpffer Pierluigi Spagnoletti Zeuli 《Genetic Resources and Crop Evolution》2007,54(8):1763-1779
Common bean (Phaseolus vulgaris L.) was introduced in Europe from both Mesoamerican and Andean centres of origin. In this study, a collection including 544
accessions from all European regions showed that the Andean phaseolin types ‘T’ (45.6%) and ‘C’ (30.7%) prevailed over the
Mesoamerican ones ‘S’ (23.7%), and accessions with cuboid seed shape (34.9%), maroon coat darker colour seed (44.3%), uniform
seed colour (69.6%) were the most frequent. European accessions with phaseolin ‘S’ showed a significantly larger average seed
size compared to those from America in the same phaseolin class while those presenting ‘T’ and ‘C’ phaseolin did not. This
suggests that, during crop expansion in Europe, sampling or selection favoured the large-seeded races within the Mesoamerican
‘S’ gene pool or, possibly, introgression from Andean germplasm did occur. A core collection was developed using sampling
approaches based on the information available in the genebank databases and on phaseolin patterns. Four sampling strategies
were used: simple random sampling, and three random-stratified samplings, by logarithm of frequency of accessions by country,
by European region, and by phaseolin pattern, respectively. Two sampling strategies resulted in core collections significantly
different for phaseolin electrophoretic patterns from the whole collection. Stratification by phaseolin patterns increased
the frequency of ‘S’ types (‘C’ type = 33%, ‘T’ type = 5.7% and ‘S’ type = 31.3%). The core collections were validated using
seven seed characters, and no significant difference was observed in all strategies. This first developed European bean core
collection will help to assess the contribution of the two American gene pools to the European germplasm and their relative
importance for breeding purposes. 相似文献
9.
Z. Abraham S. K. Malik Gangadhar Eashwar Rao S. Lakshmi Narayanan S. Biju 《Genetic Resources and Crop Evolution》2006,53(2):401-406
A collaborative crop specific exploration and collection mission to collect the germplasm and to study the population size
of male and female/hermaphrodite trees of Malabar tamarind [Garcinia cambogia (Gaertn.) Desr.] in the area of its diversity was undertaken during July 2002 in Kerala and Karnataka. A total of 56 accessions
of Malabar tamarind were collected. Two collections of Malabar tamarind were found to be very specific because of the uncommon
fruit colour, which is pinkish red. All the collected accessions are grown at National Bureau of Plant Genetic Resources (NBPGR)
Regional Station, Thrissur for characterisation and conservation. Extensive range of variability was found in fruit colour,
shape, size and nature of branching and canopy of trees. Characterisation of 13 fruit and five seed characters was done for
51 accessions. The variability was found to be maximum for nipple length (74.8%) and minimum for fruit girth (12.8%). Two
promising accessions were identified based on mean fruit weight (161 g) in IC 354028 and mean rind thickness (15 mm) and mean
rind weight (125 g) in IC 354019. 相似文献
10.
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
11.
Plant breeders are interested in strawberry species as donors of volatile compounds in breeding programmes because of the
diversity and intensity of wild strawberry aroma. Therefore, the topic of this paper is the prospective analysis of four accessions
of four wild strawberry accessions in comparison to a standard cultivar of Fragaria × ananassa Duch. by using human sensory, gas chromatography mass spectrometry (GCMS) and gas chromatography–olfactometry (GCO). The
wild species have higher aroma intensities compared with the cultivated one. The flavour quality differs significantly. Semiquantitative
GC analysis revealed that F. × ananassa cv. ‘Elsanta’ has the lowest content of volatile compounds whereas Fragaria moschata L. ‘Cotta’ has the highest. The aroma impressions, measured by GCO, support the findings of GCMS analyses. The nasal impact
frequency (NIF)-profiles of the wild types are more manifold and of higher intensities than those of the cultivated F. × ananassa cv. ‘Elsanta’ which corresponds with the overall flavour impression when tasting the fresh fruits. 相似文献
12.
Nora Scarcelli Serge Tostain Cédric Mariac Clément Agbangla Ogoubi Da Julien Berthaud Jean-Louis Pham 《Genetic Resources and Crop Evolution》2006,53(1):121-130
‘Domestication’ is a traditional farmers’ practice reported for yams (Dioscorea sp.) in Benin (West Africa). It involves introducing ‘spontaneous’ (naturally occurring) yams, supposedly wild (D. abyssinica and D. praehensilis), in varieties of the D. cayenensis–D. rotundata cultivated species complex. In this study, we established the genetic nature of ‘predomesticated’ yam plants using the amplified
fragment length polymorphism (AFLP) technique. A total of 213 accessions, consisting of 32 predomesticated yams, 70 D. cayenensis–D. rotundata, 86 D. abyssinica and 25 D. praehensilis yams were analysed. Using 91 AFLP markers, three groups of accessions were distinguished, broadly corresponding to the above
botanical species. Of the 32 predomesticated accessions, 16% were clustered with D. praehensilis, 37% with D. abyssinica and the remaining 47% with D. cayenensis–D. rotundata. These results demonstrated the use of wild plants by farmers in their domestication process, and suggested that plants derived
from intervarietal and interspecific hybridisation may also be subject to this process. This study has shown that through
domestication farmers influence and increase the genetic diversity in yam by using sexual reproduction of wild and possibly
cultivated yams. 相似文献
13.
Hoda Bashiri Kianoosh Cheghamirza Isa Arji Noshin Mahmodi 《Genetic Resources and Crop Evolution》2017,64(2):391-404
The morphological diversity and relationship among 138 pear genotypes, including 11 commercial cultivars and 127 wild pear accessions from central Zagros mountains located in the west of Iran, based on 64 morphological characters were studied. The higher coefficient of variation indicated that high level of variation was belonged to the petiole stipule, fruit the relative area of the skin color, fruit relative area periphery rust dents end, fruit relative blight on an area of skin, fruit curved tail, fruit dents end, fruit depth dents end, fruit relative area periphery patina tail connection characters. Pyrus communis L. and Pyrus glabra Boiss. species were the highest and the shortest tree, respectively. According to the cluster analysis, 138 genotypes were clustered into nine main groups. Principal components analysis revealed that the first three components accounted for 68.77 % of the total variation in data. Moreover, 19 factors justified 72.57 % of the total variation based on factor analysis. The research results showed that the Zagros mountains are the centers of diversity of pear. Therefore, it is necessary to use the Iranian genotypes as the genetic resources for improving the morphological characters of pear. 相似文献
14.
15.
Ambiguity exists about the level of genetic diversity represented by farmer crop varieties, how it develops over time and
how it relates to the diversity comprised by formal varieties. As part of an interdisciplinary technological/sociological
study on farmer management of gene flow, upland rice (Oryza sativa L.) and late millet (Pennisetum glaucum (L.) R.Br.) from The Gambia were investigated for morphological and molecular variation. The goal of these analyses was to
obtain insight into the level of crop genetic diversity of farmer’s materials planted in several case study villages in The
Gambia. For both crops, samples were collected from villages and various research institutes. Based on variety names, different
rice and millet varieties were expected to be used in different villages. In fact, there was a large overlap in genetic diversity
for both crops, masked by the use of synonyms. The considerable similarity in rice genetic diversity between villages most
likely results from the exchange of varieties between farmers. For millet this seems the result of development of varieties
from the same gene pool. Some farmer varieties of rice, however, are apparent hybrid forms between the species O. sativa and O. glaberrima Steud., and farmer varieties in general displayed higher levels of genetic diversity than formal varieties. This indicates
that, for rice, genetic diversity develops in farmers’ fields and may have potential use in formal breeding programs. 相似文献
16.
Pedro Talhinhas José Leitão João Neves-Martins 《Genetic Resources and Crop Evolution》2006,53(3):563-578
Lupinus angustifolius L. is a Mediterranean species, domesticated in the 20th century, representing an important grain legume crop in Australia
and other countries. This work is focused on the collection of wild germplasm and on the characterisation of morphological
and molecular diversity of germplasm accessions. It reports the collection of 81 wild L. angustifolius accessions from the South and Centre of Portugal, available at the ‘Instituto Superior de Agronomia Gene Bank’, with subsequent
morphological and molecular characterisation of a selection of these and other accessions. A multivariate analysis of morphological
traits on 88 L. angustifolius accessions (including 59 wild Portuguese accessions, 15 cultivars and 14 breeding lines) showed a cline of variation on wild
germplasm, with plants from Southern Portugal characterised by earlier flowering, higher vegetative development and larger
seeds. AFLP and ISSR molecular markers grouped modern cultivars as sub-clusters within the wider diversity of wild germplasm,
revealing the narrow pool of genetic diversity on which domesticated accessions are based. The importance of preserving, characterising
and using wild genetic resources for L. angustifolius crop improvement is outlined by the results obtained. 相似文献
17.
18.
Louise Willemen Xavier Scheldeman Víctor Soto Cabellos Simón Rafael Salazar Luigi Guarino 《Genetic Resources and Crop Evolution》2007,54(7):1599-1612
This study evaluates quantitatively the suitability of the use of site-specific socio-economic and environmental data as indicators
to rapidly assess patterns of diversity and genetic erosion risk in cassava. Socio-economic data as well as farmers’ estimation
of genetic erosion were collected in the study area, the Ucayali region of the Peruvian Amazon, through interviews with 285
cassava farmers in 50 communities, while diversity was assessed based on agromorphological characterization of 295 cassava
accessions. Using multivariate regression analyses, 50 and 45% of the variation in respectively diversity and genetic erosion
estimation could be explained by a selected set of socio-economic and environmental indicators. In both regression models
four out of the total of 38 variables proved to contribute significantly (at p < 0.10 level). Additionally, the study revealed that farmers are a good direct source of information on the diversity present
at community level, which can contribute to the development of methodologies to assess diversity more rapidly. The results
of this study are valuable for the development of models to rapidly assess diversity dynamics in large areas. 相似文献
19.
We investigated morphological evidence that might allow wild Pyrus spp. to be distinguished from cultivated material (Pyrus communis L.) in the North-eastern Iberian Peninsula. 134 pear trees were identified in the wild and characterized by 13 quantitative
and 13 qualitative leaf–shoot and fruit traits. The trees were visually classified into two preliminary groups of wild and
cultivated material and discriminant functions, based on a reference collection for allocating individuals to one of the groups,
were constructed. Both classifications were compared with a near-optimal numerical classification (the two-stage Ward-MLM
strategy) using two criteria. The visual assignment of trees allocated 60% of trees to the wild group and 40% to the cultivated
group. The overall discrepancy rate between the field classification and the discriminant analysis was low (17.4%). In general,
wild individuals had smaller leaves, shorter petioles and more rounded and smaller fruits than their cultivated counterparts.
They also had small-to-intermediate petiole widths, thorns on their shoots and straight or convex fruit profiles. However,
the Ward-MLM strategy always formed better groups, in terms of the two criteria used, in all the continuous and categorical
variables, for both leaf–shoot and fruit traits. Likewise, the agreement between classifications (discriminant analysis and
Ward-MLM strategy) was only partial, with some Ward-MLM groups composed of both wild and cultivated material in similar proportions.
This result suggests a limited success in identifying genuine wild individuals based on morphometric data, which can be ascribed
either to poor phenotypic diversity and lack of distinguishing traits among species or to widespread crossability and subsequent
development of hybrid/introgressant populations between wild and cultivated specimens. 相似文献
20.
C. A. Offord 《Genetic Resources and Crop Evolution》2006,53(6):1263-1272
Waratahs (Telopea spp.) are cultivated for their blooms for the international cut flower market. A morphometric study was conducted on a range of cultivated waratah varieties to determine the variability of selected characters of horticultural importance and which parents might be of value in future breeding programs. Univariate analysis of characters of 13 cultivars revealed the greatest range of variation in number of flowers, bract dimensions, flower colour and leaf margin type. Differences were observed between number of flowers per inflorescence in the T. speciosissima (Sm.) R.Br. group of accessions and the other species cultivars; interspecific cultivars with T. mongaensis, Cheel and T. oreades F. Muell. were intermediate, with a similar pattern observed in bract length and width. Multivariate analysis (canonical variate analysis – CVA) discriminated between waratah cultivars on the basis of flower colour (first axis), then flower number, bract length, leaf width and leaf margin type (axis 2). The third axis also separated leaf width, the fourth leaf length and width, and the fifth leaf apex shape, CVA was also used to explore the genetic contribution of three parent T. speciosissima cultivars to hybrid populations. Hybrids with ‘Sunflare’, ‘Sunburst’ or ‘Wirrimbirra White’ as one parent were very dispersed indicating the range of inheritance of the observed phenotypic characters, leading to the possibility of selecting individuals with the required degree of character inheritance. It was demonstrated that the Telopea speciosissima type, which forms the basis of the waratah cut flower industry, may be improved by hybridising with other Telopea species. The application of the results to the development of waratah breeding programs is discussed. 相似文献