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1.
P. N. Sivalingam D. K. Samadia Dhurendra Singh H. K. Changal Hanif Khan S. K. Sharma 《Genetic Resources and Crop Evolution》2011,58(7):1095-1103
Sixteen germplasm accessions of Prosopis cineraria with suitable horticultural traits were identified from north-western Rajasthan, India, propagated clonally by budding on
seedling rootstock and maintained in the field gene bank. Morphological characterization of seven-year-old trees of these
accessions by 21 traits indicated a lot of variation among the accessions tested. Higher number of flowers per raceme was
found in accession CIAH/K2, higher width of ripened pod in CIAH/K5, higher number of seeds per pod in CIAH/K12 and a higher
weight of seed per pod in CIAH/K6. Overall, CIAH/K16 was found to be a superior genotype for most of the useful traits. High
significant positive correlation was obtained with traits useful for horticultural values. Out of 62 random decamer primers
for random amplification (RAPD) reaction, and four minisatellite core sequence for direct amplification of minisatellite DNA
(DAMD) screened with these accessions, 12 RAPD and 2 DAMD primers were found polymorphic. Average polymorphism resolved by
these markers among the accessions was 93.2%. Genetic diversity revealed by Jaccard’s co-efficient was between 0.11 and 0.77,
and four major clusters were identified among these accessions by phylogenetic analysis using NTSYSpc-2.02e software. This
study shows the existence of high genetic diversity within these accessions. 相似文献
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3.
Hari D. Upadhyaya K. N. Reddy C. L. L. Gowda S. N. Silim 《Genetic Resources and Crop Evolution》2007,54(8):1787-1795
Pigeonpea germplasm accessions collected from low (<500 m), medium (501–1000 m), high (1001–1500 m) and very high elevation
zones (>1500 m) of Kenya were evaluated for 15 agronomic traits and seed protein content at ICRISAT, Patancheru, India. There
were significant differences (P < 0.001) among elevation zones for the number of primary and secondary branches, days to 75% maturity, pod length, seeds per
pod, 100-seed weight and seed yield. Mean values indicated that the accessions from low elevation zone were significantly
different from those collected in higher elevation zones for early flowering and maturity, number of primary branches, pod
length, number of pods per plant, seeds per pod, 100-seed weight, seed yield and harvest index. None of the accessions collected
in Kenya belonged to extra early (<80 days to 50% flowering) and early (80–100 days to 50% flowering) maturity groups, as
defined by time to flowering at Patancheru, India. Mean diversity index based on all characters indicated that accessions
from the low elevation zone are more diverse than those from the higher elevation zones. Frequency distribution for trait
extremes indicated that the accessions from the low elevation zone were early to flower and mature, short statured, produced
more primary and secondary branches with high pod bearing length, long pods, more pods per plant, more seeds per pod, a high
seed yield and harvest index. Accessions from the very high elevation zone were late flowering, with a large number of tertiary
branches, large seeds and a high shelling percentage and could be a source for cold tolerance and the breeding of vegetable
types. Results suggest that the elevation of collection sites is therefore a very important determinant of variation patterns
of pigeonpea in Kenya. 相似文献
4.
Phenotypic diversity was assessed for quantitative and qualitative traits in a salt-tolerant subset of the international safflower
(Carthamus tinctorius L.) germplasm collection originating from 11 countries in three regions (Central Asia, Southwest Asia and Africa) of the
Middle East. Phenotypically, the germplasm, among and within regions, was highly variable, especially for rosette- and yield-related
traits. Frequency of desirable variants of seven agronomically important traits ranged from 14% for long rosette period to
50% for no or few spines. Level of population differentiation was high for number of capitula per plant (30%), whereas most
traits partitioned their diversity (82–87%) within populations. Region-specific nonrandom associations among sets of qualitative
traits and the existence of broad morphological and phenotypic diversity in this germplasm were supported by the large number
of log-linear models needed to describe qualitative trait associations, the high number of principal components needed to
account for total variability, and the low discriminatory power of phenotypic traits among germplasm from regions and countries
in the Middle East. These results suggest that adaptation of the species to the wide spatial and temporal variation in the
Middle East resulted in a multitude of ecotypes and in enormous amount of local variation. A multivariate selection criterion
for high biological and seed yield, long rosette period and no or few spines identified five accessions from Southwest Asia
that can be introduced into subsistence farming systems as a multipurpose crop under saline agriculture. 相似文献
5.
An investigation was conducted to determine the extent of diversity and relationships among a worldwide safflower (Carthamus tinctorius L.) germplasm collection and to find out adapted accessions that can be used in an organic safflower breeding program in
Germany. A total of 468 accessions was studied under organic farming conditions at Kleinhohenheim experimental station during
the seasons of 2004 and 2005. All the accessions were evaluated for 12 phenotypic traits and three rated diseases. Multivariate
analyses have been used to measure the diversity in a subset of 200 accessions and 11 geographical regions. Generally, the
study showed that there was a large genetic variation within accessions. A coefficient of variation (CV%) for investigated
traits and diseases ranged from 2.9 to 91.0% with the highest CV was recorded for yield/m2, yield/plant and seeds/plant. The
most accessions that originated in Europe revealed relatively better performance compared to non-Europeans. High yielding,
early maturing, and disease tolerant accessions were identified. However, the low oil content (8.7–22.8%) is the primary concern
in this germplasm collection. The degree of heritability varied between 10% for lodging to 86% for plant height. Genotypic
coefficient of correlation (r
g) was slightly higher for many traits than the respective phenotypic coefficient. Oil content and seed yield/m2 were highly
significantly correlated (r
g = 0.78). The genotypic coefficient of correlation showed that selection for seeds/plant and thousand kernel weight was effective
for improvement of seed yield and oil content. The results of the principal component analysis and the clustering pattern
of accessions were consistent with the results of analysis of variance. About 78% of the total phenotypic diversity in the
germplasm was explained on the basis of four principal components and 88% of the total variation among geographical regions
was contributed by the first three principal components. The distribution of the accessions within clusters has no apparent
relationship with the geographical origin. However, many of the European accessions have a tendency to stay together. 相似文献
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Tien-hor Wu Svein O. Solberg Flemming Yndgaard Yu-Yu Chou 《Genetic Resources and Crop Evolution》2018,65(1):271-283
Cleome gynandra L. is a leafy vegetable native to sub-Saharan Africa and Asia and cultivated on dry areas. The plant plays an important role in the food and nutrition security of local communities. The objective of this study was to illustrate variation and diversity in the Cleome collection held at the World Vegetable Center. In total, 242 accessions were cultivated and morphologically characterized and analyzed. The gynophore and filament, both important organs of the flower, played a key role in taxonomical identification. High morphological variation was detected in traits including plant height, pod length, leaf size, flower color, and earliness. Distinct morphological differentiation was detected between Asian and African accessions. On average, the African accessions were larger, less uniform and later in flowering and seed maturation than the Asian accessions. The results were used to establish a core collection of 49 Cleome accessions. Gaps in the current collection were detected. High within-accessions diversity challenges the existing ex situ conservation system; to maintain diversity, seed should be collected from a large number of plants, both during the collection mission and in ex situ regeneration. The results are relevant for germplasm collection strategies and regeneration protocols for good genebank practices. 相似文献
8.
Malik Ashiq Rabbani Yoshie Murakami Yasuhisa Kuginuki Kenji Takayanagi 《Genetic Resources and Crop Evolution》1998,45(4):307-316
Genetic diversity of 30 radish (Raphanus sativus L.) accessions was investigated at the phenotypic level with morphological characters and at the DNA level using the random amplified polymorphic DNA (RAPD) technique. Thirty-six morpho-physiological traits were recorded from seedling stage to harvest. The 31 primers used generated 202 RAPD bands, of which 158 (78.2%) were polymorphic. Multivariate procedures were used to classify the germplasm on the basis of phenotypic traits and RAPD fragments. Dendrograms were generated for the Euclidean distance from the morphological data and the Nei's genetic distance from the RAPD markers. Phenotypically, all the accessions were classified into four major groups corresponding to the different forms of cultivated radish. The morphological diversity existing within each of these groups suggested that they should be discriminated into the three botanical convarieties, sativusT (large-rooted), caudatus (pod-type) and oleifer (oilseed-type). Clustering of the accessions did not show any pattern of association between the morphological characters and the collection sites. Instead, landrace groups were associated with their morphological similarities and horticultural uses. On the other hand, the intra-specific genetic relationships of several accessions based on RAPD analysis were related primarily to their collection sites rather than to their phenotypic affinities. The level of polymorphism exhibited by the various convarieties could be exploited in genetic mapping populations to tag economically important traits. These genotypes also could serve as a useful germplasm source for root, leaf, pod and seed. This preliminary study of traditional radish landraces from Pakistan provides useful information regarding their horticultural potential. 相似文献
9.
H. D. Upadhyaya K. N. Reddy C. L. L. Gowda Sube Singh 《Genetic Resources and Crop Evolution》2007,54(6):1167-1184
The pigeonpea core collection developed at ICRISAT genebank consists of 1,290 accessions from 53 countries. The core collection,
which includes selected lines in extra early, early, medium and late maturity groups was evaluated for 18 qualitative and
16 quantitative characters during the 2004 rainy season, to assess the phenotypic diversity and determine the relative importance
of different characters in evaluating pigeonpea germplasm accessions. The four maturity groups differed significantly for
all characters under study. The medium maturity group showed significantly higher mean number of primary, secondary and tertiary
branches, number of racemes, pod bearing length, pods per plant, shelling percent and plot seed yield. Late maturity group
showed significantly higher mean for leaf size, plant height, pod length, seeds per pod and 100-seed weight, indicating this
group as a good source of vegetable pigeonpea. Significant positive correlations were found between number of secondary branches
and pods per plant in extra early group (r = 0.756), late maturity group (r = 0.776) and entire core (r = 0.728) and between number of racemes and pods per plant in all maturity groups and entire core. Principal coordinate and
principal component analysis showed that seven qualitative and nine quantitative traits were important in explaining multivariate
polymorphism. The Shannon–Weaver diversity index (H′) varied for different maturity groups and traits. Phenotypic diversity, averaged over all the 16 characters, increases from
extra early group (0.36 ± 0.04) to late maturity group (0.42 ± 0.04) suggesting that medium and late maturity groups have
greater diversity compared to extra early and early maturity groups. 相似文献
10.
W. H. Ntundu S. A. Shillah W. Y. F. Marandu J. L. Christiansen 《Genetic Resources and Crop Evolution》2006,53(2):367-378
A field experiment was conducted in Tanzania for two seasons to assess the genetic diversity of bambara groundnut landraces
based on morphological characters. One hundred accessions collected from a wide range of agricultural zones in the country
were evaluated in a 10 × 10 triple lattice block design at Maruku station in Bukoba, Tanzania. For the qualitative characters
evaluated, considerable morphological variations were observed for growth habit, pod shape and pod colour. Quantitative morphological
characters such as peduncle length, number of leaves per plant, terminal leaflet width, terminal leaflet length, petiole length,
plant spread, plant length, pod width, seed length, seed width, number of pods per plant, shelling percentage and days to
50% flowering showed significant variation among accessions for the two test seasons. Multivariate analysis for 15 quantitative
morphological traits that showed significant variation indicated that the first four PCs with eigenvalues ≥1 accounted for
63.0 and 65.0% of the total variance among the accessions during the two test seasons, respectively. The most important loadings
for PC1 and PC2 for the two seasons were terminal leaflet width, terminal leaflet length, petiole length, plant spread, plant
height and pod length, pod width, seed length, seed width, numbers of pods per plant. Cluster analysis grouped bambara groundnut
accessions into three major groups with respect to their geographic origins. Based on this present study, bambara groundnut
landraces from Tanzania displayed a considerable diversity for morphological and agronomic traits useful for germplasm management
and utilization into crop improvement. 相似文献
11.
为研究观赏向日葵品种资源表型性状多样性,改良现有观赏品种,筛选出有市场前景的观赏向日葵新品种,对30份观赏向日葵种质资源的11个质量性状和7个数量性状进行变异系数、相关性分析,采用系统聚类组间聚合的方法根据欧式距离进行聚类分析。结果表明,观赏向日葵种质的表型性状具有丰富的遗传多样性。在质量性状中, Shannon-Wiener 多样性指数最高的是舌状花颜色(1.408 7),舌状花杂色的分布频率为40.00%。数量性状中,变异系数从大至小依次为舌状花宽、舌状花瓣数、舌状花长、株高、花朵数、SPAD值、分枝长。基于表型性状,在遗传距离为10处将供试的30份种质划分为3个群组,第I群组共包含有12个种质,第II群组共包含14个种质,第III群组有4个种质。 相似文献
12.
Variation among Spanish faba beans cultivars: taxonomic and evolutionary implications 总被引:1,自引:0,他引:1
Summary Univariate and multivariate analysis were used to examine phenotypic variability within a Spanish faba bean germplasm collection maintained at the Centro de Investigación y Desarrollo Agrario, Córdoba, Spain.The analysis of 158 Spanish faba bean accessions and 12 quantitative traits indicated highly significant differences among botanical groups for 8 characters and among geographic regions for 10 characters. An east to west clinal pattern of variation for some characters was detected.In order to identify the main characters which account for the major variation, the same collection was subjected to principal component analysis for 12 quantitative traits. Reproductive and plant height characters appeared to be the major sources of diversity.To determine the importance of both geographic and botanical variation among the Spanish cultivars, discriminant analysis was applied. According to these analyses, plant height, height of the lowest pod-bearing node, pod length and 100 seed weight, were important traits discriminating among different geographic regions. The main character discriminating among botanical groups was the 100 seed weight.Our results fit in a pattern in which both agroecological and anthropological causes could have played a role in the observed variation. This analysis can help plant breeders in choosing the most favorable accessions in plant breeding. 相似文献
13.
Biyun Chen Kun Xu Jun Li Feng Li Jiangwei Qiao Hao Li Guizhen Gao Guixin Yan Xiaoming Wu 《Genetic Resources and Crop Evolution》2014,61(5):979-999
It is important to evaluate yield and agronomic traits when selecting for elite lines in Brassica napus L. In this study, 488 global collections of B. napus L. were evaluated for yield and agronomic traits during two consecutive years under growing conditions in central China. A series of phenotypic data for yield and agronomic traits were obtained. Large variations in yield and agronomic traits were found among these accessions, making selection possible for these characters. Chinese accessions, in general, tended to have higher plot yield (POY), higher seed yield per plant (PY), higher thousand-seed weight (TSW), more seeds per silique (SS), and fewer siliques per plant (PS) than foreign accessions. Comparing winter, semi-winter, and spring accessions, semi-winter accessions tended to have the highest POY, highest PY, highest TSW, most SS and fewest PS. Genotypic variation for TSW accounted for 71.23 % of the total variation, and it was the highest for all 12 of the phenotypic traits. Significant correlations were observed between different traits. Principal component analysis (PCA) revealed that significant variation among the traits with the first four principal components could explain 49.8 % of the total variation. Three major groups (winter, spring and semi-winter oilseed rape accessions) could be distinguished when projecting the accessions onto the first two PCAs. The information on variations in yield and agronomic traits detected in this study provided useful parents for rapeseed breeding. Moreover, the phenotypic data on yield and agronomic traits obtained may be used in our subsequent genome-wide association studies for B. napus. 相似文献
14.
Gemechu Keneni Mussa Jarso Tezera Wolabu Getnet Dino 《Genetic Resources and Crop Evolution》2005,52(5):539-549
An experiment was conducted in 2001 at Holetta and Kulumsa, Ethiopia, to study the extent and pattern of genetic diversity
in Ethiopian field pea (Pisum sativum L.) landraces. One hundred forty-eight germplasm accessions were grown in an alpha lattice design with 2 replications. Data
on 12 traits were collected and analyzed. Differences among the accessions were significant for most of the traits (except
number of seeds/ pod) at each location even though differences pooled over location were mostly non-significant. The accessions
were grouped into five clusters of different sizes. Accessions from the southern part of the country (Arsi) distributed overall
clusters while those from the northern half (North and South Wello, North Gonder and North Shewa) fell into clusters C1 to C3. Cumulative effects of a number of characters dictated differentiation of the accessions into clusters. There was no definite
relationship between geographic diversity and genetic diversity as overlapping was encountered in clustering pattern among
accessions from different parts of the country. Accessions from different regions might have similar genetic background and
those from the same origin might also have different genetic background. Therefore, geographic diversity should not necessarily
be used as an index of genetic diversity and parental selection should be based on a systematic study of genetic diversity
in a specific population. Genetic distances among most of the clusters were significant that crosses between parents selected
out of them are expected to generate desirable genetic recombination. Selection should also consider the special advantages
of each cluster and each accession within a cluster. Future germplasm collection, conservation and breeding efforts should
focus not only on inter-regional diversity but also on intra-regional diversity. 相似文献
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16.
Michael Dossett Nahla V. Bassil Kim S. Lewers Chad E. Finn 《Genetic Resources and Crop Evolution》2012,59(8):1849-1865
Breeding progress in black raspberry (Rubus occidentalis L.) has been limited by a lack of genetic diversity in elite germplasm. Black raspberry cultivars have been noted for showing very few phenotypic differences and seedlings from crosses between cultivars for a lack of segregation for important traits. Despite these challenges, little molecular work has been done to explore genetic diversity and relationships in wild and cultivated black raspberry germplasm. Microsatellite, or simple sequence repeat (SSR), markers are highly polymorphic codominant markers useful for studying genetic diversity, population genetics, genetic fingerprinting and other applications. We examined genetic diversity in 148 wild and cultivated black raspberry accessions using 21 polymorphic SSR markers. Black raspberry cultivars clustered tightly and showed higher than expected heterozygosity while that of wild accessions was low. Relationships between wild black raspberry accessions were poorly resolved and regional clusters were mostly absent from our analysis. Our results indicated that wild black raspberry germplasm is a relatively untapped resource available for future breeding. 相似文献
17.
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
18.
Knowledge of the genetic diversity in the germplasm accessions is important for the efficient germplasm management. We studied
45 colored rice accessions, which had been earlier collected from peninsular India. The accessions were evaluated at two diverse
locations for 12 morpho-agronomic traits and genotyped using 50 simple sequence repeat (SSR) markers. Significant genotypic
variability was observed for all morpho-agronomic traits studied. Dendrogram and principal component analysis based on morpho-agronomic
traits separated the accessions into three clusters. The first two principal components accounted for 82% of the total variation.
The most discriminatory traits were number of grains per panicle, biomass yield, and days to flowering and maturity. The SSR
analysis revealed high polymorphic information content value of 0.84. Though, Mantel test did not show a significant correlation,
yet the classification based on phenotyping and genotyping data showed good agreement for the expression of morpho-agronomic
traits in the formation of clusters. Five accessions had high concentration (> 100 μg/g) of Fe and one of Zn. Our study revealed
the presence of large genetic variation among the colored rice accessions evaluated and moderate agreement between morpho-agronomic
and SSR–based classifications and of these with geographic diversity. 相似文献