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1.
Sweet chestnut (Castanea sativa Miller) is the only native species of the genus Castanea in Europe. A collecting mission has been carried out in Andalusia (South of Spain) with the purpose to evaluate of the genetic
variability of this species in this region. During the field trips, two different types of chestnut trees have been detected:
one of clonal nature (varieties obtained by graft) and other of sexual nature (trees derived from nut). For the former, 156
trees were located in plantations in the Genal river Valley (Malaga) and the Natural Park of `Sierra de Aracena y Picos de
Aroche' (Huelva), where 43 varietal denominations were recorded. Thirty out of them had never been mentioned. For the latter,
29 stands were located in Almería, Córdoba, Granada, Jaén, and Málaga. This work reveal that this species present a high degree
of genetic variability. Nevertheless, their preservation is seriously threatened in the most zones due to the varietal substitution,
the low profit or the abandonment, which determinate the urgent necessity to safeguard these genetic resources. 相似文献
2.
Victor Hugo Franco Mora Omar Franco-Mora José Antonio López-Sandoval Delfina de Jesús Pérez-López Artemio Balbuena-Melgarejo 《Genetic Resources and Crop Evolution》2009,56(5):719-727
As a country, Mexico presents an especially wide range of fruit germplasm diversity. Tepexi de Rodríguez, Puebla, Mexico,
belongs to The Tehuacán-Cuicatlán Valley, which is an arid zone recognized to have a flora diversity. In that place, wild
plum (Ximenia americana L. var. americana; Olacaceae), locally named “tihuixocote” grows mainly in backyards, the fruit of this species is appreciated by native people
due to its taste, which is reported to be a mixture between sweet and sour. Fruit from 15 trees were characterized by measuring
bio-physical and bio-chemical parameters, including weight, diameter (equatorial and polar), relationship equatorial/polar
diameters, total sugar, soluble solid content and phenolic compounds. The results of this study indicate variability for these
various wild plum fruit characteristics among trees growing in a reduced territorial space. 相似文献
3.
4.
La diversité des conditions d’environnement (roche-mère, climat, végétation) prévalant dans un massif de moyenne montagne (Vosges, France) nous a permis d’établir leur rôle dans la manifestation à des degrés divers des propriétés andiques dans le sol. Nous avons examiné un lot de 13 profils sélectionnés à partir de critères lithologiques, climatiques et morphologiques présumés favorables à l’expression de ces propriétés andiques: roches-mères basiques d’origine volcanique ou non, climat montagnard très humide, abondance de matière organique sur une grande profondeur. Ces profils se subdivisent en deux populations. Quatre d’entre eux peuvent être classés comme des Andisols (Alic Fulvudands) alors que les autres ont des propriétés andiques trop faiblement exprimées pour appartenir à cet ordre et doivent être classés comme des Andic Haplumbrepts. Tous ces sols sont dépourvus d’allophanes. Dans cet environnement de moyenne montagne, les facteurs favorables à la manifestation de propriétés andiques sont d’une part, les altitudes et les expositions qui induisent de faibles températures et de fortes précipitations et d’autre part, l’altérabilité des roches-mères déterminée par leur composition chimique et minéralogique. Comme les vieux matériaux volcaniques sur lesquels se développent la plupart des sols étudiés sont pauvres en verres, voire complètement dévitrifiés, les Andisols vosgiens présentent beaucoup d’analogies avec les Andisols non-allophaniques non-volcaniques identifiés dans d’autres environnements. Leurs propriétés andiques sont faiblement exprimées et elles sont dues à la présence de complexes organo-métalliques associée à des teneurs élevées en carbone organique. The diverse environmental conditions (parent material, climate, vegetation) in the Vosges Mountains (France) allow us to investigate their role in the development of soils with varying degrees of andic properties. We studied 13 profiles selected on the basis of lithological, ecological and morphological criteria assumed to favour the formation of andic properties, i.e. basic parent materials of volcanic and other origins, wet montane climates and accumulation of thick layers of organic matter. The profiles belong to two classes: four are Andisols, more precisely Alic Fulvudands, and the others are Andic Haplumbrepts with only weakly expressed andic properties. In this montane environment the factors favouring the andic properties seem to be on the one hand height and exposure inducing cold and humid microclimates, and on the other the chemical and mineralogical composition controlling the weatherability of the soil’s parent materials. For example, the old volcanic rocks on which most of the soils occur are poor in glassy material or are even completely devitrified. Accordingly, Andisols in the Vosges are like those of non-volcanic, non-allophanic Andisols elsewhere in the world: their andic properties are weakly expressed and are caused by organo-metallic complexes associated with their upper organic-rich horizons rather than by allophanes. 相似文献
5.
B. Algayer B. Wang H. Bourennane F. Zheng O. Duval G. Li Y. Le Bissonnais F. Darboux 《European Journal of Soil Science》2014,65(3):325-335
Soil interrill erodibility is a key component of soil erosion models. However, when using aggregate stability to assess soil erodibility, samples are usually collected from the plough layer, while soil erosion occurs at the soil surface. Hence, the potential changes in erodibility caused by crusting are ignored. Moreover, soil interrill erodibility is difficult to predict accurately. This lack of predictability means that current erosion models use a constant erodibility value for a given soil, and thus do not consider potential heterogeneity of erodibility. This study was conducted to (i) assess the heterogeneity of aggregate stability for a crusted soil and (ii) relate this heterogeneity to the aggregate stability of the underlying material (sub‐crust) and to standard soil properties. A field study was conducted in a small area of the Loess Plateau in China in which the crust and the sub‐crust soils were sampled. Standard soil properties (organic matter content, sand content, silt content, clay content, cation exchange capacity (CEC), pH in water, and water content at the time of sampling) were measured as potential explanatory factors of aggregate stability. The results showed a large heterogeneity in aggregate stability among the sites, even though the sites had the same soil type. The mean weight diameter (MWD) of the crust varied between 0.33 and 2.04 mm while the MWD of the sub‐crust varied between 0.23 and 1.42 mm. Soil texture and pH were uniform among the sampling sites, whereas water content, organic matter content and CEC varied more. Even though some correlations existed (for example r = 0.57 between MWD for the slow wetting test and organic matter content), none of the standard soil properties was able to predict aggregate stability accurately. The aggregate stability of the crust was significantly greater than that of the sub‐crust. The large differences in aggregate stability imply large differences in soil interrill erodibility. Because a single soil type was investigated, this finding proves that erodibility can vary greatly in space even for a given soil type. Soil interrill erodibility should be estimated from the exact material exposed to erosive forces, the soil surface material. Using the sub‐crust would have led to greatly over‐estimated erodibility and thus to a marked bias in erosion model predictions. Résumé La stabilité structurale d'un sol encroûté : différences entre la croûte et le matériau sous‐jacent, et conséquences pour l'estimation de l'érodabilité inter‐rigole. Un exemple dans le Plateau de Loess (Chine) L'érodabilité inter‐rigole est un paramètre clef des modèles d'érosion du sol. Cependant, lorsque des tests de stabilité structurale sont utilisés pour évaluer l'érodabilité, les mesures sont habituellement réalisées sur des échantillons prélevés dans l'horizon labouré alors que l'érosion a lieu à la surface du sol. Ainsi, les changements potentiels d'érodabilité causés par la formation de croûte sont ignorés. De plus, l'érodabilité inter‐rigole reste encore difficile à prédire avec précision. Ces difficultés conduisent les modèles d'érosion à utiliser une érodabilité constante pour un type de sol donné, et donc à ne pas considérer l'hétérogénéité potentielle de l'érodabilité. Cette étude a été conduite pour (i) évaluer l'hétérogénéité de la stabilité structurale pour un sol encroûté et (ii) relier cette hétérogénéité à la stabilité structurale du matériau sous‐jacent (sous‐croûte) et aux propriétés standards du sol. Une étude de terrain a été réalisée sur un secteur de surface limitée du Plateau de L?ss (Chine). Des échantillons provenant de la croûte et de la sous‐croûte ont été collectés. Les propriétés standards (teneur en carbone organique, teneurs en sable, limon et argile, CEC, pH, et teneur en eau au prélèvement), ont été mesurées en tant que facteurs explicatifs potentiels de la stabilité structurale. Les résultats ont montré une grande hétérogénéité de la stabilité structurale entre les différents sites alors que ces derniers présentaient le même type de sol. Le MWD de la croûte variait entre 0.33 et 2.04 mm tandis que le MWD de la sous‐croûte variait entre 0.23 et 1.42 mm. La texture du sol et le pH étaient très homogènes entre les sites étudiés, tandis que la teneur en eau, la teneur en matière organique et la CEC variaient plus fortement. Bien que certaines corrélations aient été identifiées (par exemple r = 0.57 entre le MWD du test à l'humectation lente et la teneur en carbone organique), aucune de ces propriétés n'a permis de prédire précisément la stabilité structurale. La stabilité structurale de la croûte était significativement supérieure à celle de la sous‐croûte. Les grandes différences de stabilité structurale mesurées impliquent des érodabilités très contrastées. Comme un seul type de sol a été étudié, ce résultat prouve que l'érodabilité peut être très variable spatialement pour un type de sol donné. L'érodabilité inter‐rigole du sol devrait être mesurée sur le matériau exact qui subit l'érosion, c'est‐à‐dire le matériau de surface. L'utilisation du matériau sous‐jacent aurait engendré une forte surestimation de l'érodabilité et donc un biais important dans les prédictions d'un modèle d'érosion. 相似文献
6.
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
7.
B. Leviel B. Gabrielle E. Justes B. Mary G. Gosse 《European Journal of Soil Science》1998,49(1):37-51
Pollution of the environment by nitrogen (N) has emerged as a serious concern in agriculture, especially in the case of crops such as oilseed rape. To assess the effect of N fertilization on N dynamics, the movements of water and nitrate were determined in a rendzina near Châlons-en-Champagne (eastern France) cropped with oilseed rape with three levels of fertilizer N and in a bare control. From in situ micrometeorological measurements, actual evapotranspiration rates were computed with an energy budget and used to calibrate an evapotranspiration model based on meteorological data and crop leaf area index. Water flow below 120 cm was then deduced from periodic measurements of soil moisture contents and precipitation, and the associated nitrate leaching fluxes were calculated from the NO3 concentration measured at the same depth. Denitrification rates and ammonia volatilization were monitored in the field after fertilizer applications, and crop assimilation of nitrogen was determined frequently during the growth cycle. A nitrate budget gave an approximation of the in situ net mineralization fluxes. The water balance was influenced by the crop and its fertilization: the crop's canopy and roots enhanced the water loss by evapotranspiration and contributed to diminish the soil water storage, whereas drainage volumes were about the same for all cropped treatments, and significantly greater in the bare soil. The rainy winter was particularly favourable to leaching, and losses were much greater (+ 41%) under the over-fertilized crop than under the non-fertilized one, but remained less (– 42%) than those under the bare control soil. Bilans hydriques et azotés d'une culture de colza sur rendzine avec différentes doses d'engrais Les pollutions de l'environnement par l'azote sont devenues une préoccupation majeure en agriculture, particulièrement dans le cas des cultures comme le colza. Pour évaluer les effets de la fertilisation azotée sur la dynamique de l'azote, les transferts d'eau et de nitrate d'une rendzine ont été mesurés près de Châlons-en-Champagne (Est de la France) sur des parcelles expérimentales de colza avec trois niveaux de fertilisation azotée et sur une parcelle témoin en sol nu. A partir de mesures micrométéorologiques in situ, l'évapotranspiration réelle a été calculée par bilan énergétique de la surface du sol, et un modèle d'évapotranspiration ayant pour entrées des données météorologiques classiques et l'indice foliaire de la culture a été calibré. Le flux net d'eau sous 120 cm a été alors déduit de mesures périodiques de teneur en eau du sol et de précipitations, et les flux de nitrate associés ont été calculés à partir des concentration mesurées à la même profondeur. Les flux de dénitrification et la volatilisation d'ammoniac ont été mesurés au champ après les apports d'engrais; l'absorption d'azote par la culture a été déterminée fréquemment pendant le cycle de croissance. Enfin, un bilan azoté a donné l'ordre de grandeur de la minéralisation nette. Le bilan hydrique a été influencé par la culture et sa fertilisation: le couvert végétal et les racines ont accentué les pertes d'eau par évapotranspiration et par conséquent le stock d'eau, tandis que la lame d'eau drainée était à peu près la même pour tous les traitements cultivés, et significativement plus élevée pour le sol nu. L'hiver particulièrement pluvieux a été très favorable au lessivage, et les pertes ont été beaucoup plus fortes (+ 41%) sous la culture sur-fertilisée que sur la culture non-fertilisée, mais elles sont restées inférieures (– 42%) à celles sous sol nu. Nomenclature 相似文献
8.
L. P. Canellas J. G. Busato L. B. Dobbss M. A. Baldotto V. M. Rumjanek F. L. Olivares 《European Journal of Soil Science》2010,61(3):375-383
We employed CP/MAS 13C NMR spectroscopy and classical humus fractionation to evaluate the behaviour of soil organic matter (SOM) resulting from long‐term sugar cane production when harvested without burning. Soil samples were collected at two depths (0–0.2 and 0.2–0.4 m) from a tropical Entisol cropped with sugar cane for 55 years at Campos dos Goytacazes (Brazil), either with or without burning crop residues when harvesting. Continuous incorporation of sugar cane residues increased carbon (C) content and promoted changes in SOM, including increases in humins, humic acids and aromatic C moieties. Sequential extraction methods showed enhanced amounts of available forms of nitrogen (N), sulphur (S) and phosphorus (P). Moreover, 31P NMR analysis revealed an increase in organic P as diester phosphates of plant origin in the humic acids fraction. The increased macronutrient bioavailability of labile forms of N, P and S could be partially related to the more hydrophobic nature of SOM observed in soil samples collected from areas that were not burnt. These results show that the long‐term non‐burning management of sugar cane harvest promotes the hydrophobic character of SOM and a more conservative and sustainable management of soil fertility. Matière organique du so let stockage de nutriments en manègement de longue durée et pas brûlé de la cane au sucre Résumé Le comportement de la matière organique du sol (MOS) a étéévalué sur une plantation de canne à sucre de longue durée, sans brûlis, par spectroscopie CP/MAS 13C NMR et la méthode classique de fractionnement et caractérisation de l’humus. Des échantillons de sol ont été prélevés dans une plantation de canne à sucre en culture continue depuis 55 ans, installée à Campos dos Goytacazes (Brésil) sur un entisol tropical. L’échantillonnage a été réaliséà 0–0.2 m et 0.2–0.4 m de profondeur sur des parcelles sous différents modes de mise en culture: parcelles comportant des récoltes précédées de brûlis des résidus et d’autres sans brûlis. L’incorporation continue des résidus de canne à sucre a provoqué l’augmentation du carbone (C) et des variations de la matière organique du sol (MOS), avec notamment l’augmentation des teneurs en humines, acides humiques et carbone aromatique. Les méthodes d’extraction séquentielle ont permis de détecter l’augmentation des quantités d’azote (N), de soufre (S) et de phosphore (P) disponibles. En outre, l’analyse RMN 31P effectuée sur les fractions d’acides humiques a révélé une augmentation des quantités de phosphore organique sous forme de diester de phosphates d’origine végétale. L’augmentation de la biodisponibilité de macronutriments (formes labiles de N, P et S) pourrait partiellement être attribuée au caractère hydrophobe de la matière organique plus expressif sur les échantillons de sol prélevés dans les parcelles sans brûlis. Ces résultats montrent que la pratique de non‐brûlis des résidus, à long terme, dans les plantations de canne à sucre, favorise le caractère hydrophobe de la matière organique du sol provoquant une gestion plus conservatrice et durable de la fertilité des sols. 相似文献
9.
The pink stem borer (Sesamia nonagrioides Lef.) is the main corn (Zea mays L.) pest in the Mediterranean area. Although, screening for resistance to this pest has been successful, the level of resistance
shown by the most resistant varieties is not high. The objectives of the present work were: (i) the evaluation for pink stem
borer resistance of the nontested inbred lines, field and popcorn materials, from the collection maintained at the Misión
Biológica de Galicia and (ii) the study of the performance, under pink stem borer infestation, of inbreds selected for resistance
to pink stem borer in hybrid combination. Forty four inbred lines nontested yet for resistant to pink stem borer along with
five inbred lines previously reported as resistant to stem and ear attack, were evaluated in 2002 and 2003. In adjacent experiments,
hybrids EP79× W552, EP77× B93, and A661× EP42 were tested along with a resistant hybrid, MEB531-Bt, and a susceptible hybrid, INRA 260. New sources of resistance to pink stem borer have been detected among inbred lines improving
the level of resistance presented by previously tested inbreds. Some of these lines were successfully developed by pedigree
selection for resistance to pink stem borer. 相似文献
10.
J. Francisco-Ortega A. Santos-Guerra R. Mosa-Coello E. González-Feria D. J. Crawford 《Genetic Resources and Crop Evolution》1996,43(1):33-39
Germplasm from one or more populations of each taxon of the Macaronesian endemic genus Argyranthemum Sch. Bip. (Asteraceae: Anthemideae) was collected in the Canary Islands, Madeira, the Selvagens Islands and the Desertas Islands. A total of 253 germplasm samples was collected and they are conserved ex situ at the seed bank of Centro de Investigación y Tecnología Agraria de Canarias (Tenerife, Canary Islands, Spain). Duplicates are held at the germplasm bank of Escuela Técnica Superior de Ingenieros Agrónomos (Madrid, Spain). A preliminary account of the ecogeography of the genus based on field observation is provided. In situ conservation strategies are discussed, particularly with regard to the occurrence of hybridization within Argyranthemum.Abbreviations IUCN
international Union for Conservation of Nature
- CITA
Centro de Investigación y Tecnología Agraria de Canarias
- ETSIA
Escuela Técnica Superior de Ingenieros Agrónomos, Madrid 相似文献
11.
Isabelle Blanckaert Martín Paredes-Flores Francisco J. Espinosa-García Daniel Piñero Rafael Lira 《Genetic Resources and Crop Evolution》2012,59(4):557-573
Use and management of wild and weedy species may involve artificial selection, which can determine morphological, physiological,
reproductive, and genetic divergences between wild and managed populations, resulting in the initial or incipient phases of
plant domestication. In this study we combined ethnobotanical, morphological, phytochemical and genetic information for analyzing
differences between managed and unmanaged populations of the Mexican edible weed, Epazote (Chenopodium ambrosioides L.), in Santa María Tecomavaca, Oaxaca, a rural community within the Tehuacán-Cuicatlán Biosphere Reserve, Mexico. Our hypothesis
was that differences in morphology (e.g. leave dimensions and density of pubescence), phytochemistry (e.g. flavor, odor, and
amount of strong scented and toxic compounds) and/or molecular genetic markers, between managed and wild populations of Epazote
in Santa María Tecomavaca, would indicate that managed populations have been and/or are under a process of incipient domestication.
Our results revealed the existence in the study area of morphological variants associated with a gradient of management intensity,
which involved apparent improved palatability correlated with a lowering of chemical defense. Most remarkably, we found agreement
in the groupings defined by the cluster analyses of morphological and genetic data. Although Epazote is considered a weed
or, at best, a minor crop, the results from four lines of evidence (cultural differentiation patterns, gigantism, reduction
in chemical defenses, toxic compounds and inheritance of adaptive traits) suggest the existence of an incipient domestication
process in the study zone. 相似文献
12.
Jaroslava Cieslarová Petr Smýkal Zuzana Dočkalová Pavel Hanáček Stanislav Procházka Miroslav Hýbl Miroslav Griga 《Genetic Resources and Crop Evolution》2011,58(3):439-451
Maintaining germplasm genetic integrity is a key objective of long-term ex situ conservation. Periodic regeneration, performed on limited plots with small number of individuals, increases the risk of genetic
drift and genetic diversity changes. In this study, six accessions of white flowered, dry seed pea varieties (Pisum sativum L. subsp. sativum var. sativum): Bohatyr, Klatovsky zeleny, Hanák, Moravsky hrotovicky krajovy, Raman and Viktoria-75 and four accessions of colour flowered,
fodder pea (P. sativum subsp. sativum var. arvense (L.) Poiret: Arvika, Česky banán, Moravská krajová and Niké, representing Czechoslovak varieties and landraces, bred over
the last 40–80 years, were analyzed using ten microsatellite locus specific markers. Each accession was represented by 20
individual seeds of two temporally different samples, spanning the period of 20 or 40 years. Together with intra-accession
variation (except of cv. Hanák), evidence of genetic changes, e.g. differences in allele frequencies as well as genetic composition
of sample, was detected in six out of ten accessions (Arvika, Bohatyr, Česky banán, Moravsky hrotovicky krajovy, Moravská
krajová and Raman). Evidence of genetic erosion was found in three accessions (Česky banán, Moravsky hrotovicky krajovy and
Raman), while in another three (Arvika, Bohatyr and Moravská krajová) the level of diversity was found to have increased.
Moreover in three samples of Bohatyr (2004) and Klatovsky zeleny (1963 and 2004), low levels of heterozygosity was detected.
These results demonstrate that in pea, a self-pollinating and highly homozygous plant, the danger of the loss of genetic integrity
exists. These findings are significant for long-term ex situ germplasm management. 相似文献
13.
Gabriella Sonnante Anna Vittoria Carluccio Roser Vilatersana Domenico Pignone 《Genetic Resources and Crop Evolution》2007,54(3):483-495
The evolutionary history of artichoke and cultivated cardoon and their relationships to wild allies of the genus Cynara are not fully understood yet. To try resolve the evolutionary patterns leading to the domestication of these two crops, a
study of molecular evolution was undertaken. The species C. cardunculus, including artichoke, cultivated and wild cardoon, together with four wild Cynara species were taken into consideration. Internal (ITS) and external (ETS) rDNA transcribed spacers were used as markers of
nuclear genome, the psbA-trnH spacer as a marker of chloroplast genome. Sequences were analysed using phylogenetic analysis packages. Molecular data indicate
that the whole genus is quite recent and that the domestication of artichoke and cultivated cardoon, crops diverging for reproduction
system and use, are independent events which diverge in time and space. As for wild Cynara species, an evolutionary pattern consistent with their present geographical distribution was hypothesized in relation to
the climatic changes occurring in the Mediterranean during the last 20 millennia: C. humilis and C. cornigera appeared to have differentiated first, C. syriaca and C. baetica were differentiated in a second period, while C. cardunculus showed to be the most recent and plastic species. The high plasticity of C. cardunculus has not only allowed its nowadays wide distribution, but has also given the potential for domestication.
Dedicated to the memory of Richard Neville Lester (1937–2006) who greatly contributed to the understanding of the evolution,
domestication, and genetic resources of eggplants as well as to the biosystematics and taxonomy of allied species.
IGV Publication N. 78 of the Institute of Plant Genetics, CNR 相似文献
14.
Brenda Oaxaca-Villa Alejandro Casas Alfonso Valiente-Banuet 《Genetic Resources and Crop Evolution》2006,53(2):277-287
Reproductive biology of the columnar cactus Escontria chiotilla was analysed in wild and silvicultural managed populations in the Tehuacán Valley, Central Mexico, where this cactus is under
domestication because of its edible fruits. Anthesis is diurnal, flowers opening between 8:00 and 17:00 h, the period between
12:00 and 13:00 appearing to be crucial in pollination success since at this time the maximum opening of flowers, turgidity
of stigma, and activity of flower visitors, as well as the highest nectar production and pollen release occur. The bees Apis mellifera, Bombus pensylvanicus and Xylocopa mexicanorum, and the hummingbirds Amazilia violiceps, Cynanthus sordidus and Cynanthus latirostris were the most frequent flower visitors during the crucial period, and were observed contacting both stamens and stigma of
E. chiotilla. No differences were found in anthesis nor in flower visitors among both population types. Distances separating the populations
studied and bridges of individuals of E. chiotilla between them are within the radius that bees and hummingbirds may travel, indicating that spatial barrier to pollen flow
are unlikely. Breeding system is self-incompatible. Production of flowers occurs during the whole year in both population
types, allowing continual pollen flow among them. This observation confirms reports of high gene flow among the populations
studied in previous population genetics studies. The high pollen flow among wild and managed population explains that however
the occurrence of artificial selection, the process of domestication is in incipient stages presumably because gene flow counteracts
effects of artificial selection. 相似文献
15.
J. Gebauer K. El-Siddig B. A. El Tahir A. A. Salih G. Ebert K. Hammer 《Genetic Resources and Crop Evolution》2007,54(8):1701-1708
The small leaved white cross berry (Grewia tenax [Forssk.] Fiori) is a fruit-producing deciduous shrub or small tree of widespread occurrence in semi-arid and sub-humid tropical
climates. Despite its well-recognized potential and high prices on local markets, there are no commercial plantations in Sudan.
Wild plants have continuously been used to meet the growing commercial demand for their fruits. Recently, there has been an
increased interest in finding alternative, potentially high-value cash crops to improve the income of small farmers who are
currently depending upon growing and selling millet (Pennisetum glaucum [L.] R. Br.), sorghum (Sorghum bicolor [L.] Moench), sesame (Sesamum indicum L.), and groundnut (Arachis hypogaea L.). G. tenax has often been cited as a prime candidate for domestication as a useful horticultural plant. One major factor hampering this
development is the limited and scattered knowledge available on this species. The purpose of this paper is to highlight the
importance of G. tenax by providing information on its botanical and horticultural characteristics in the effort to promote its domestication and
commercialization for regional and global markets. 相似文献
16.
Elena Zuriaga José M. Blanca Laura Cordero Alicia Sifres William G. Blas-Cerdán Rafael Morales Fernando Nuez 《Genetic Resources and Crop Evolution》2009,56(1):39-51
Solanum pimpinellifolium, due to its close relationship to S. lycopersicum, has been a genetic source for many commercially important tomato traits. It is a wild species found in the coastal areas
of Peru and Ecuador. In this study, the genetic variation of S. pimpinellifolium was studied using the diversity found in 10 microsatellites in 248 plants spread throughout its entire distribution area,
including Ecuador, which has been underrepresented in previous studies. Peruvian and Ecuadorian accessions are genetically
quite differentiated. A possible cause of these differences could be the non-uniform nature of the coastal Ecuadorian and
Peruvian climates, seeing as an important correlation between genetic differentiation and climate has been found. In addition,
Ecuadorian and south Peruvian accessions have a lower genetic diversity and a higher homozygosity due to their higher autogamy,
lower population size, and possible colonization bottlenecks. The Galápagos Islands population is an extreme case, with no
diversity, likely caused by a recent colonization from the northern continental Ecuadorian region where genetically identical
plants have been found.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Elena Zuriaga and José M. Blanca contributed equally to this work. 相似文献
17.
Western Ghats, one of the megadiversity hotspots, hold a rich treasure of diversity in Momordica L. comprising M. charantia var. muricata, M. charantia var. charantia, M. dioica and M. sahyadrica. Vernacular names of these species vary from place to place. Traditional uses of these species comprising food, medicinal
and cosmetic, culinary preparations, vernacular names in local dialects and taboos and religious beliefs relating to their
domestication and folk taxonomy are dealt with in this paper. 相似文献
18.
To improve understanding of diversity of Lablab purpureus and establish relationships among 103 germplasm accessions collected from diverse geographic origins, amplified fragment
length polymorphism markers were used. Four primer sets selected out of 16 produced 289 clear, repeatable polymorphisms. UPGMA
analysis of similarity data clustered the accessions according to their subspecific taxonomic organization, i.e., subsp. purpureus and subsp. uncinatus, as well as to cultivated and wild forms. The well-represented landraces from Africa and Asia, belonging predominantly to
subsp. purpureus, displayed moderate genetic diversity. Wild forms from Africa showed far greater levels of diversity that would justify taxonomic
re-assessment of the wild subsp. uncinatus. The molecular analysis identified forms that were collected in the wild in India but were genetically placed intermediate
between wild and cultivated forms. As these plant types did not exist among the African accessions, it is suggested that they
might represent escapes from early attempts of domestication. These results support the suggested pathway of domestication
and distribution of L. purpureus from Africa to Asia. Additional members to a previously published core collection of the species are proposed. 相似文献
19.
Abdelfattah Badr Hanaa H. El-Shazly Linda E. Watson 《Genetic Resources and Crop Evolution》2008,55(1):21-31
The origin and ancestry for Egyptian clover, Trifolium alexandrinum, was examined using AFLP data. The data support a close relationship of T. alexandrinum accessions from Syria and Egypt to T. apertum, T. berytheum, and T. salmoneum. However, crossability and geographic distributions suggest that T. apertum is an unlikely progenitor. In contrast, T. salmoneum appears to be the most probable progenitor for Syrian material of Egyptian clover, although a close relationship to T. berytheum was also revealed. The ability of these species to cross freely indicates that T. salmoneum and T. berytheum may be regarded as the primary ancestors from, which man domesticated Egyptian clover through artificial selection in Syria.
Following domestication, the earlier forms of the crop species could have been taken into rain-fed cultivation in Palestine
and irrigated cultivation in Egypt. In this regard, the domestication of Egyptian clover may be analogous to other crops,
such as barley and wheat, which were also domesticated in the Fertile Crescent and taken into cultivation in the Nile Valley.
It appears that genetic improvement of the crop occurred in Egypt after cultivation, and that the varieties that were developed
in Egypt were later distributed worldwide. 相似文献
20.
Jorge Cunha Margarida Baleiras-Couto José P. Cunha Jorgete Banza Adelaide Soveral Luís C. Carneiro José E. Eiras-Dias 《Genetic Resources and Crop Evolution》2007,54(5):981-988
Wild populations of Vitis vinifera L.␣have been located in Portugal. Morphological characterization was carried out in three populations located in Alcácer
do Sal, Castelo Branco, and Montemor-o-Novo, and then compared using multivariate discriminant analysis. These populations
were from three different hydrological basins, therefore cross-pollination was not possible. It was verified that in each
population all plants were different. The data suggest that the frequency of female and male plants is rather variable in
wild populations. The morphology of the adult leaf, from the Alcácer do Sal population, had particular features when compared
with Castelo Branco and Montemor-o-Novo populations, which were more homogeneous. The length of teeth compared with width
at the end of the base, and the density of prostrate hairs between and on main veins (lower side) were the variables which
allowed the best discrimination among populations. 相似文献