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1.
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
2.
R. Moreno J. A. Espejo A. Cabrera T. Millán J. Gil 《Genetic Resources and Crop Evolution》2006,53(4):729-736
A study has been conducted into the genetic variation analysis of the tetraploid asparagus landrace ‘Morado de Huetor’ and
its relationship with current commercial cultivars using Random Amplified Polymorphic DNA (RAPD) molecular markers. The presence
of different ploidic levels in the ‘Morado de Huetor’ landrace has been also studied using cytogenetic analysis. Ten decamer
oligonucleotides were used to obtain RAPD markers and to characterise 52 individuals of ‘Morado de Huetor’, 7 of the tetraploid
cultivar ‘Purple Passion’, and 55 of 5 diploid hybrid commercial cultivars. Jaccard similarity index was calculated and a
cluster analysis using UPGMA (Unweighted Pair-Group Method using Arithmetic Average) was performed. Tetraploid asparagus,
‘Morado de Huetor’ and ‘Purple Passion’, were well differentiated from the diploid ones showing a higher genetic variability.
This result suggests a different origin for tetraploid and diploid asparagus varieties. Within the diploid cultivars a variety
distribution was obtained. A specific monomorphic band (OPB20883) was found in tetraploid varieties. Within the diploid cultivars, two bands (OPB20830, OPC15705) can be used to distinguish between the hybrid cultivars used in this study. Tri-, penta-, hexa-, and octoploid plants were
found in ‘Morado de Huetor’. The origin of these ploidic levels is discussed and their use in the development of new varieties
is proposed. In conclusion, ‘Morado de Huetor’ is a genetic resource that could be used to increase the narrow genetic background
reported in diploid asparagus cultivars. 相似文献
3.
4.
This study is focused in the main chestnut growing areas from north- to south-western Spain. We studied 50 accessions corresponding
to 22 cultivars named by local growers; 11 from Andalucía, 9 from Castilla-León, and 2 from Extremadura. These were compared
with 22 types classified previously in Galicia (82 accessions). Ten morphological traits and five isoenzyme systems were used
to classify them and establish genetic relationships. A lower genetic variability has been found in Extremadura (middle Spain)
and Andalucía (south) than in Galicia (north western) which may be because of the lower importance of the crop in those areas
and the geographic barriers between them. Galicia could be the origin of the types found in Castilla-León, Extremadura, and
south-western Andalucía, and the types found in Central Andalucía were closer to those found in Castilla-León and Extremadura.
Most accessions studied (117/132) could be classified positively, making 37 out of 44 cultivars found from northern to southern
Spain. Three groups of synonymies were found in Castilla-León: ‘Brava’ and ‘Negral’, ‘Gallego’ and ‘Injerto’, and ‘Rapega’
and ‘Verdello’. Most of the Spanish types have been propagated as a principal clone. Variability within the types is important
and must be considered to select the best clones as cultivars. 相似文献
5.
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
6.
Cengiz Toker 《Genetic Resources and Crop Evolution》2009,56(1):7-12
Two distinct chickpeas of the domestic chickpea, C. arietinum L., exist and are referred to as ‘desi’ or microsperma and ‘kabuli’ or macrosperma. Cicer reticulatum Ladiz. is considered to be the wild progenitor of the domestic chickpea. However, the morphological variation in 18 original
accessions of C. reticulatum is narrower than those of the domestic chickpeas. The aim of the study is to increase the variability in C. reticulatum. In M2 generation, a mutant with white flower color was isolated despite of the fact that the parent has the pink flower. Although
seed coat color of the parent was dark brown, the mutant was cream like ‘kabuli’ chickpea. It is commonly accepted that the
large seeded domestic ‘kabuli’ chickpeas originated from the small seeded ‘desi’ chickpeas, but the induced mutants (white
flower and cream seed coat color) of C. reticulatum may suggest an additional path for the evolution of ‘kabuli’ chickpea. ‘Kabuli’ chickpeas could have originated from spontaneous
mutants of C. reticulatum. In M3 generation, multipinnate leaf, erect growth habit, green seed and double-podded chickpeas were isolated. Among these progenies,
morphologic variability increased and approached domesticated chickpea. Based on historical records and the induced mutants
obtained from this study, the domestic ‘kabuli’ chickpea could have directly emerged from C. reticulatum in ancient Eastern Turkey. 相似文献
7.
Ali M. Missaoui Andrew H. Paterson Joseph H. Bouton 《Genetic Resources and Crop Evolution》2006,53(6):1291-1302
Information regarding the amount of genetic diversity is necessary to enhance the effectiveness of breeding programs and germplasm conservation efforts. Genetic variation between 21 switchgrass genotypes randomly selected from two lowland (‘Alamo’ and ‘Kanlow’) and one upland (‘Summer’) synthetic cultivars were estimated using restriction fragment length polymorphism (RFLP) markers. Comparison of 85 RFLP loci revealed 92% polymorphism between at least two genotypes from the upland and lowland ecotypes. Within ecotypes, the upland genotypes showed higher polymorphism than lowland genotypes (64% vs. 56%). ‘Kanlow’ had a lower percent of polymorphic loci than ‘Alamo’ (52% vs. 60%). Jaccard distances revealed higher genetic diversity between upland and lowland ecotypes than between genotypes within each ecotype. Hierarchical cluster analysis using Ward's minimum variance grouped the genotypes into two major clusters, one representing the upland group and the other the lowland group. Phylogenetic analysis of chloroplast non-coding region trnL (UAA) intron sequences from 34 switchgrass accessions (6 upland cultivars, 2 lowland cultivars, and 26 accessions of unknown affiliation) produced a neighbor-joining dendrogram comprised of two major clusters with 99% bootstrap support. All accessions grouped in the same cluster with the lowland cultivars (‘Alamo’ and ‘Kanlow’) had a deletion of 49 nucleotides. Phenotypic identification of greenhouse-grown plants showed that all accessions with the deletion are of the lowland type. The deletion in trnL (UAA) sequences appears to be specific to lowland accessions and should be useful as a DNA marker for the classification of upland and lowland germplasm. 相似文献
8.
L. Pecetti M. Romani L. De Rosa E. Franzini G. Della Marianna F. Gusmeroli A. Tosca R. Paoletti E. Piano 《Genetic Resources and Crop Evolution》2008,55(7):939-947
A recent approach to restoration of degraded mountain landscapes (e.g. ski slopes) recommend to sow seed mixtures including
‘site-specific’ species, i.e. native germplasm adapted to the prevailing conditions and ecologically compatible with the area
of intervention. To better exploit the potential of these species and enhance their spread in revegetation projects, deeper
knowledge is needed, however, on the existing variation in their germplasm, particularly for economically useful traits such
as seed yield. Snow clover is one of the recommended ‘site-specific’ legumes. This study evaluated 12 populations of snow
clover, collected in three valleys of the Rhaetian Alps, Italy, to assess their variation and highlight any promising material.
The evaluation encompassed a mountain and a lowland site, to verify the behaviour of the germplasm also in one environment
markedly different from that of origin. Differences among valleys were observed for flower colour, growth habit and type,
flowering time and susceptibility to mildew, although the overall pattern of phenotypic diversity was similar among valleys.
Some effect of the evaluation site on the expression of morphological and seed production traits, and on the overall diversity,
was also evident. Furthermore, the lowland site experienced very high plant mortality towards the end of the first growing
season. Individual populations proved a valuable source of variation for seed production. Some populations, in particular,
were worth of attention for a possible selection of high-seed-yielding snow clover cultivars. An assessment of the mating
system suggested a lack of self-tripping or an almost absolute self-incompatibility in snow clover. 相似文献
9.
Potato production from true seed, or true potato seed (TPS) is not a new system for this vegetatively propagated crop. Andean farmers have grown potatoes in the cool highlands from true seed for many centuries. TPS appears today as a promising technology in the warm tropics, where diseases impede the production of pathogen-free potato propagules. However, the identification of suitable genetic resources for potato seed production requires the selection of clones that lack antagonism between tuber growth and seed embryo development. Furthermore, the potential TPS parents need to possess characteristics of a sexually propagated crop that is grown for the harvest of its vegetative part, i.e., the tuber. This new process of domestication requires a change in the selection methods, which starts by assessing the potential of available potato clones for both reproductive characteristics and agronomic traits, particularly those of the tuber. Tetraploid landraces and cultivars of the pathogen-tested collection of the Centro Internacional de la Papa were assessed for reproductive and agronomic characteristics during three consecutive years in San Ramón, a Peruvian location in the warm lowland tropics. The clones showed significant variation for all characteristics recorded. The Shannon–Weaver diversity index (H) was highest for flowering duration (0.617) and intensity (0.600). The lowest H was calculated for bee attraction in this location. The overall H was not significantly affected by the year-to-year variation, but some of the characteristics recorded (e.g. flowers per inflorescence, anther type, style length, plus fruit and berry set) showed distinct H according to the year of assessment. Some of the cultivars with promising TPS traits, as determined by their reproductive characteristics, also had outstanding tuber set, weight and yield. Furthermore, hybrid offspring from the selected clones from the pathogen-tested elite sample, did show high tuber yield with appropriate tuber set and reproductive traits as shown by progeny testing. Hence, the approach followed for identifying parental sources as discussed in this article appears to be appropriate. 相似文献
10.
For the selection of donors with valuable characteristics for breeding, 39 thyme accessions were evaluated in three years
according to a staggered schedule. The criteria investigated were: winter hardiness, beginning of flowering, growth height,
yield of the dry herb, content of essential oil, composition of the essential oil, DNA content of cell nuclei and number of
chromosomes. The most strongly varying traits between the populations were the yield of dry herb, the content of essential
oil and the content of volatile phenols with coefficients of variation (CV) between CV 40% and 50%. The largest variation
within a population was detected for the yield of dry herb (CV 25–46%) and the content of essential oil (CV 17–48%). The homogeneity
of the populations was different. The minimal average coefficient of variation of all traits (CV 19%) was determined in the
population of the cultivar ‘Varico II’ and in a population from Lithuania. The ploidy level of T. vulgaris was diploid (2n = 30). 相似文献
11.
Elizabeth Rice 《Genetic Resources and Crop Evolution》2007,54(4):701-713
Using survey data from Jala, Mexico, this case-study evaluates in situ maize conservation of the variety ‘Jala’ (Zea mays L.). Though historically ‘Jala’ was the dominant variety grown in the valley of Jala, today less than 20% of farmers grow
it on only 5% of the maize area. Younger growers of the ‘Jala’ variety specialize in it, growing relatively large amounts
for niche markets. Older, diversified farmers grow small areas for household use and to compete in a local contest. Conservation
of the ‘Jala’ variety has been heavily influenced by shifting ideal concepts of maize, as determined by market and consumption
demands and by a contest designed to promote in situ conservation. The current move away from nationalized purchasing may
favor ‘Jala’s’ continued conservation. 相似文献
12.
A cultivated tetraploid asparagus landrace ‘Morado de Huetor’ growing in the South of Spain has been collected and conserved
ex situ in two experimental plots. This landrace has been reported to have an interspecific hybrid origin (A. officinalis × A. maritimus). A 59% of the total farmer plots cultivated in the region were visited and ripe fruits collected from 10 female plants per
plot. Fruits from a total of 300 plants were collected and two half sibs descendents from each one were sown separate in two
plots. Of the 88 farmer plots visited, the landrace was growing only in 34, in the rest the crop had been removed. Hence,
‘Morado de Huetor’ is in a very high risk of disappearing. Now this landrace is conserved ex situ in two experimental plots with sufficient number of plants to represent their maximum variability in order to be used in
plant breeding. 相似文献
13.
14.
Pigeonpea is an important pulse crop grown by smallholder farmers in the semi-arid tropics. Most of the pigeonpea cultivars
grown to date are selections from the landraces, with a narrow genetic base. With the expansion of the crop to newer areas,
problems of local importance are to be addressed. Hence, an economically feasible and faster germplasm evaluation mechanism,
such as a core collection, is required. This article describes the development of core collection from 12,153 pigeonpea accessions
collected from 56 countries and maintained at ICRISAT, Patancheru, India. The germplasm accessions from 56 countries were
placed under 14 clusters based primarily on geographic origin. Data on 14 qualitative morphological traits were used for cluster
formation by Ward’s method. From each cluster ≈10% accessions were randomly selected to constitute a core collection comprising
1290 accessions. Mean comparisons using Newman–Keuls test, variances’ comparisons by Levene’s test, and comparison of frequency
distribution by χ2-test indicated that the core collection was similar to that of the entire collection for various traits and the genetic variability
available in the entire collection is preserved in the core collection. The Shannon–Weaver diversity index for different traits
was also similar for both entire and core collection. All the important phenotypic associations between different traits available
in the entire collection were preserved in the core collection. The core collection constituted in the present study facilitates
identification of useful traits economically and expeditiously for use in pigeonpea improvement. 相似文献
15.
In this study, we investigated the genetic variation of allelopathic potential, its grey correlation with important agronomic
characters, and rank analysis on allelopathic stability of fifteen wheat accessions commonly grown in arid regions of the
Loess Plateau in China. The genetic variation of allelopathic property in dryland winter wheat showed significant differences
between accessions. Allelopathic effects exhibited high heritability (55–95%) throughout the life cycle of wheat. Heritability
was highest in the tillering stage and weakest in the seed filling stage. Allelopathic potential varied and was discontinuous
throughout the wheat life cycle. Grey correlation analysis indicated a close relationship between allelopathic potential dependant
on growth phase and agronomic characters. Allelopathic expression during some growth periods induced a partial correlation
effect on some important agronomic characters that affected wheat yield. Allelopathic heritability and its degree of influence
on yield were more evident in the vegetative growth stage compared to the reproductive stage. A multiple linear regression
was built between allelopathic potential during different growth periods and agronomic characters pursued in wheat breeding.
Allelopathic potential had a linear effect on production traits cultivated in wheat breeding. When allelopathic intensity
varied from 0 to 1 in the reproductive stage, plant height ranged from 44 to 108 cm, spike length from 6.4 to 9.2 cm, number
of spikelets with seeds from 13.4 to 21.0, mean seed number per spike from 41.5 to 50.3 and thousand seed weight from 36.2
to 38.3 g. Based on rank analysis, we concluded that there was a synergistic relationship between allelopathic potential in
wheat and genetic, chemical and ecological factors. Triticum aestivum L. ‘No 6 Lankao’ and T. aestivum L. ‘No 22 Xiaoyan’ were identified as stable and relatively strong allelopathic accessions, whereas T. aestivum L. ‘Lankao 95–25’ was a stable but relatively weak allelopathic cultivar. Other varieties showed unstable allelopathic potential. 相似文献
16.
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
17.
The multispecies freshwater biomonitor a potential new tool for sediment biotests and biomonitoring 总被引：1，自引：0，他引：1
Behavioural changes are used as early warning systems for water quality monitoring or as rapid and sensitive endpoints in
toxicity bioassays. In this study, the automated measurement of behavioural patterns of the thrichopteranHydropsyche angustipennis (Curtis 1834) has been recorded for the first time in sediment with the Multispecies Freshwater Biomonitor, MFB. The MFB
recorded different types of behaviour in sediment with the same accuracy as in water. Behavioural differences of the larvae
exposed to ‘water only’ and ‘sediment only’ have been described. In ‘choice’ experiments, the larvae preferred the ‘water
only’ compartment. 相似文献
18.
Zizania latifolia, which belongs to the tribe Oryzeae, has been cultivated for more than 2000 years and has historically been used in China
mainly as an aquatic vegetable. In China, the largest area under cultivation of this plant is located in the regions surrounding
Tai Lake, in the provinces of Jiangsu and Zhejiang. Two main types of cultivars have been developed, in one the shoots can
be harvested only once, in the fall; in the other, the shoots may be harvested twice in the fall and once the following summer.
Z. latifolia can be bred and conserved through clonal propagation as a means of preventing infection of flowering stems by the epiphyte
Ustilago esculenta. At the end of the harvest period, healthy individuals and the plants with black spots in the shoots are removed, and those
with a healthy clone will be identified and selected as ‘seed’ for the next year. 相似文献
19.
Genetic diversity in 24 advanced breeding lines of cotton was studied by using six amplified fragment length polymorphism
(AFLP) primer-pairs and 14 morphological characters. The six selected AFLP primer-pairs generated a total of 535 amplification
products, of which 460 were found to be polymorphic resulting in 85.9% polymorphism. The observed genetic distances using
AFLP markers ranged from 30% to 87% with an average of 34%. A wide range of variability was observed for all the morphological
traits studied. The range in taxonomic distance was from 0.60 to 2.77. Most of the lines could be clustered in two major clusters
in both the analyses. But the correlation coefficient between the pair-wise distances estimated from AFLPs and the average
taxonomic distances estimated from morphological characters was found to be 0.04. UPGMA cluster analysis revealed inconsistencies
in the clustering patterns, as the co-phenetic correlation coefficient between the dendrograms for morphological and AFLP
data indicated a poor fit for the two data types. From combined information, genotypes ‘RST-12’, ‘H 1226’, ‘P 348’, ‘KDCAKD’,
‘CISV 24’ and ‘H1222’ were found to be distinct from rest of the material. 相似文献