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1.
The principal economic species of the genus Melilotus are white sweet-clover (Melilotus albus) and the extremely similar yellow sweet-clover (M. officinalis). Although they are widely recognized as distinct species, some influential references in North America reduce the former to a subspecific rank or even merely a conspecific synonym of the latter. Given their importance and the large numbers of germplasm collections, the doubt needs to be resolved. This review of relevant published evidence finds that in addition to the difference in floral colour, the traditional segregation of the two as distinct species is best supported by very strong reproductive barriers as well as divergent DNA sequences in three barcoding genes. Additional but weaker confirmation of separateness is provided by studies reporting differences in external morphology, biochemistry, seed protein profiles, karyotype and DNA microsatellites.  相似文献   

2.
In Arnica montana L. (Asteraceae) two subspecies are described, A. montana subsp. atlantica (AMA), present only on the Iberian Peninsula and A. montana subsp. montana (AMM) with a very wide distribution area. The morphological differences between the two subspecies are small and variable. Therefore, this concept is sometimes questioned. To establish the genetic background of the two subspecies, populations of AMA and AMM together with herbarium samples and DNA Bank material of AMM were tested with 12 microsatellite markers. A. montana propagates by seeds or by clonal propagation of its rhizome. In AMA, clonality was frequent while in AMM only one case of clonality could be identified. Therefore, further results were clone-corrected. Genetically, AMA separated very well from AMM with a GST between the subspecies of 0.81, genetically justifying the subspecies concept of A. montana. Genetic variability in AMA (Hexp?=?0.28) was lower than in the AMM populations (Hexp?=?0.70). A somewhat higher fixation index of AMA (FST?=?0.17, compared to an FST?=?0.08 for AMM) may indicate that geneflow in AMA is a bit more restricted than in alpine AMM. However, the fixation index of AMA is not deviating from Hardy–Weinberg equilibrium. No inbreeding was observed for AMA (FIS?=?0.10) and AMM (FIS?=?0.08).  相似文献   

3.
Allium siculum Ucria is a perennial bulbous plant that occurs in Bulgaria as A. siculum subsp. dioscoridis (Sm.) K. Richt. The plant is locally known as “samardala”. Its herbage is used traditionally by local communities in Bulgaria as edible green and for preparation of salty spice mixtures. The study was focused on the documentation of traditional knowledge about samardala, covering local collection and cultivation practices, processing methods and consumption preferences. The respondents (aged 30–86 years, 50% over 65) were local producers and small-scale salesmen of the herbage and samardala-containing spices. To assess the health features of samardala spices the total phenol and flavonoid content was measured in home-consumed or marketed flavoured salts. Overall appreciation of the plant and related food products was found to be very high; presenting a considerable engagement of the locals in plant cultivation and gathering, laborious processing and consumption. Traditional ecological knowledge about the biology, phenology and ecology of the samardala plant and methods for its processing is still preserved by elderly people who rely mostly on their own cultivated plants. Although the introduction of modern appliances has altered the method of production, its main stages and the recipes are preserved. Modernization of the processing method has not affected the quality of the products and faster processing could be a contributing factor for the higher content of biologically active substances. Phenolic content was about twice as low as the flavonoid content, following the same pattern for all tested flavoured salts. Measures for better management of natural populations and promotion of cultivation practices of A. siculum subsp. dioscoridis would ensure the sustainable quality of traditional products as well as conservation of the natural plant resources.  相似文献   

4.
A set of experimental introgression lines of Triticum aestivum L. cv. Novosibirskaya 67 (N67)—Triticum polonicum L. line IC 12196 was developed using a small-scale bulk breeding method. The linkage map in chromosome 7A was constructed using F2 hybrids of N67/IC12196 and 34 microsatellite markers. The P gene was flanked by the centromeric markers, Xgwm890 (18.6 cM) and Xbarc108 (20.0 cM) on the long arm of chromosome 7A. Among 124 introgression lines, 118 lines were hexaploid (2n = 6x = 42), and 6 were tetraploid (2n = 4x = 28). Among hexaploid accessions, 68 were long-glumed, whereas 50 were normal-glumed. Thirty-four polymorphic microsatellite markers were scored for either the N67 alleles or IC 12196 alleles in 124 introgression lines derived from N67/IC 12196. The UPGMA dendrogram showed five clusters; Cluster 1 mainly contained hexaploid introgression lines with long glumes. Although the alleles around the P locus were recombined with IC1296 alleles, the distal end of the chromosome contained N67 alleles. Cluster 2 mainly contained normal glumed, hexaploid introgression lines. These predominantly had the N67 alleles on the long arm of chromosome 7A and the short arm proximal to the centromere. Cluster 3 contained long-glumed, hexaploid wheat lines with relatively high level of recombination. Cluster 4 contained non-parental alleles. Cluster 5 contained the group of tetraploid wheat lines. These tetraploid lines have IC12196 alleles on both arms of chromosome 7A. The frequency spectrum of parental alleles and chromosomal blocks among introgression lines suggested that T. aestivum – T. polonicum hybridization can rapidly give rise to a new landrace due to selective introgression of the P gene.  相似文献   

5.
The recent treatment of Triticum by Mac Key (2005) (broad species concept) is compared to the classical treatment by Dorofeev et al. (1979, English translation expected) (narrow species concept). A detailed infraspecific treatment was abandoned by Mac Key. Following his revision, names for many of the infraspecific taxa become obsolete. This is regarded to be a disadvantage for biodiversity and genetic resources studies. We propose maintaining ×Triticosecale Wittm. as a nothogenus, with ×T. rimpaui Wittm. for octoploid races, ×T. neoblaringhemii A. Camus for hexaploid races and ×T. semisecale (Mac Key) K. Hammer et A. Filat. (new combination) for tetraploid races.  相似文献   

6.
The wild grapevine [Vitis vinifera L. subsp. sylvestris (Gmelin) Hegi] is the Eurasian dioecious ancestral form of mostly monoecious domesticated cultivars (Vitis vinifera subsp. vinifera). There are different hypotheses about grapevine pollination, varying from insect to wind pollination to spontaneous self-pollination. The aim of this paper is to update our knowledge on the biology of the wild grapevine by studying the insects visiting their inflorescences. During the fieldworks, floral visitors were observed, captured and identified. The most frequent insects visiting both sexes of wild grapevine were beetles (55%) followed by bees (45%). The present study shows that although in vineyards the wind may play a role in the cross-pollination, insects can contribute to the reproductive success of the wild grapevine. The knowledge of inflorescence-visiting insects, which potentially can act as pollinators may represent an important contribution to the conservation perspective of wild grapevine.  相似文献   

7.
The paper reports on the study of DNA methylation patterns in chromosomes of an octoploid selection obtained from an amphiploid Avena barbata × Avena sativa ssp. nuda, their alteration and plant structural changes induced by 5-azacytidine (5-azaC) treatment. Subtelomere/telomere regions and some chromosomes remained heavily methylated after this practise. The increased concentration of 5-azaC strengthened the demethylation process. NOR rDNA loci on five and 5S rDNA doubled loci on three pairs of chromosomes were detected. Some 5S loci were colocalised with NORs. The number of active NORs was increased by one homologous pair after demethylation and this was related to minor loci. The NORs were mainly located on A/D genomes. Patterns of nucleoli fusion varied between main and lateral roots and demethylation increased the number of uninucleolar nuclei. Seed germination was inhibited and plant growth decreased under demethylation. 5-azaC also induced distinct anomalies in endosperm development. Extensive parts of the tissue were composed of defected cells or remained empty. Polyploidised clones of starchy or aleurone cells were observed, as were aleurone cells exhibiting new rare phenotypes.  相似文献   

8.
The purpose of this study was to characterize and identify potential new uses for perennial horsegram (Macrotyloma axillare) and horsegram (M. uniflorum) germplasm in the USDA, ARS collection. Seven morphological and yield parameters were studied in 11 M. axillare and 32 M. uniflorum accessions. A wide variation was found in stem branching, foliage, plant height, seed number, and seed weight. Leaf anthocyanin indexes were significantly higher than control flowers from PI 345729. Phytochemical traits exist in both species for potential use as nutraceuticals, forage, and food for humans.  相似文献   

9.
Aegilops triuncialis L. (2n = 4x = 28, genome formula UUCC) has been used to obtain one of the “Arsenal collection”, the distant hybridization of Triticum aestivum L. The introgression line 124/00i, which was derived from the cross of T. aestivum ‘Rodina' with γ-irradiated pollen of an accession of Ae. triuncialis. However, undesirable genes can be incorporated into the cultivated varieties from Ae. triuncialis. The spikes of Ae. triuncialis disarticulate from stems at a single node at the bottom of the spikes. It was defined as a synaptospermic diaspore. However, the spike of 124/00i unexpectedly disarticulate below each spikelet showing wedge type of disarticulation. The brittle rachis gene Br 124 (B rittle r achis of 124 /00 i ) of 124/00i was allelic to Br2 located on the short arm of chromosome 3A. From the microsatellite mapping, the Br 124 gene was bracketed by Xbarc19 (20.3 cM) and Xgwm779.1(14.3 cM) on the short arm of chromosome 3A. The present study suggested that the dominant mutation from synaptospermic diaspore to wedge type disarticulation occurred in the gamete of Ae. triuncialis when Ae. triuncialis pollen was treated with γ-irradiation.  相似文献   

10.
A simulation model of the 90Sr dynamics in the soil and stand components of deciduous forest ecosystems with a 1-day step was developed; this model was used to conduct numerical experiments to clarify the mechanisms of the 90Sr behavior. The algorithm allows one to take into account the effect of meteorological, phenological, and physiological factors on the behavior of the radionuclide and simulate different fallout conditions. The results of simulation can be used in the valuation of deciduous forest products. The model is applicable for studying the redistribution of calcium in the stand of deciduous forest ecosystems.  相似文献   

11.
TriticumThinopyrum amphiploids arose from the need to obtain forage grasses highly resistant to pest, drought, soil salinity and frost and they can be used as efficient bridges to transfer desired genes from wheatgrass species to wheat. One of them is trigopiro SH16 INTA, it was introduced in Argentina in 1947 but its genomic composition was unknown. The aim of this work was to determine the chromosome number and genomic and chromosome composition of trigopiro SH16 INTA in order to use it in breeding programs. The simultaneous use of the in situ hybridization technique with different probes (genomic DNA of Th. ponticum (Podp.) Barkworth et D.R. Dewey, pSc119.2 and pAs1) allowed us to conclude that the chromosome number of trigopiro SH16 is 2n = 42 and the genome composition would be: 14 chromosomes of the B genome, the 2D and 4D chromosome pairs of wheat, 14 chromosomes of the J genome of Thinopyrum and the remaining chromosomes probably belong to the A genome of wheat.  相似文献   

12.
According to Pliny the Elder and other Greco-Roman geoponics, Raetica was a famous white grape as well as a white wine produced in Raetia, a Province of the Roman Empire. Does Raetica grape have modern descendants? Etymologically and geographically, the white ‘Rèze’ from Valais (Switzerland) would be the best candidate. Using available microsatellite data, we searched for relatives of ‘Rèze’ in our database containing over 1,700 genotypes of grape cultivars from all over the world. Twelve cultivars showing putative first-degree (parent–offspring or full-siblings) or second-degree (grandparent–grandoffspring, uncle–nephew or half-siblings) relationships with ‘Rèze’ were then analysed at 60 microsatellite markers. Calculation of allele sharing and likelihood ratios between competing relationship categories revealed that four cultivars had parent–offspring relationship with ‘Rèze’: ‘Cascarolo Bianco’ (Piedmont, Italy), ‘Arvine Grande’ (Valais, Switzerland), ‘Groppello di Revò’ and ‘Nosiola’ (Trentino, Italy). Given that some of these are also said to be Raetica descendants, we may well be on the tracks of Pliny the Elder’s Raetica grape. However, there is no evidence about the identity of Raetica. Analysis of ancient DNA of grape pips excavated from archaeological sites of the Roman times might provide key information. Our first attempts were unsuccessful, but analysis of additional samples and optimisation of the method could provide groundbreaking results about the identity of the grapes cultivated in classical antiquity.  相似文献   

13.
Wild diploid Solanum species with an endosperm balance number (EBN) of one are a rich source of disease resistance, pest resistance, and tuber quality traits. They are not sexually compatible with 4× 4EBN or 2× 2EBN forms of the cultivated potato. In this study, the wild 2× 2EBN Mexican species S. verrucosum (ver) was used as a bridge species to access 2× 1EBN germplasm. Hybrids (V1) were created between ver as a female parent and the 1EBN species S. cardiophyllum, S. chancayense, S. commersonii, and S. trifidum. Most of the V1 hybrids were successfully crossed as females to cultivated 2× 2EBN clones. However, due to stylar barriers, reciprocal crosses were unsuccessful. Additional studies are underway to determine the effectiveness of ver as a bridge to introgress specific traits from 2× 1EBN germplasm into the cultivated potato.  相似文献   

14.
The classification of Mexican maize (Zea mays L.) begun since the early 20th century, it was consolidated during the middle of this century, but recent additions and rearrangements have been performed by several authors employing new methods of analysis and collections from diverse origin; nevertheless, maize from the State of Michoacan, Mexico has received little attention in regard to its systematic classification. Maize populations from the Tarasca Mountain Chain in Michoacan are commonly considered in literature, as belonging to the Chalqueño race; however, closer observations indicate that significant differences do exist, suggesting the necessity of performing an in-depth study on this respect. Thirty nine native maize populations from the Tarasca Mountain Chain region were evaluated along with 19 typical populations of the Chalqueño, Celaya and Conico races coming from the States of Mexico, Puebla, Hidalgo, Querétaro and Oaxaca. Populations were evaluated in Aranza, Michoacan and Montecillo, Mexico State. Seventeen morphological characters were scored and analyzed by one-way analyses of variance and multivariate techniques. Populations were also genetically analyzed through 17 isozyme loci. Native populations had some alleles not found either in the Chalqueño, Celaya or Conico races, and possess larger genetic diversity. Local populations were congregated into a discrete group apart from the typical Chalqueño populations, suggesting that landraces from the Tarasca Mountain Chain region might not be considered as belonging to the Chalqueño race, but they integrate by themselves a different race.  相似文献   

15.
A new species of Manihot has been collected from Fortaleza, Ceará state, Brazil. It was grown at the living collection in the experimental station, University of Brasilia since 1980 and left for natural reproduction. It bred true during all these years giving rise to identical typical plants of the ancestor one. The closest species to it is M. glaziovii. Apparently this new species was formed by sporadic hybridization between M. glaziovii and cassava itself in its natural habitat, Ceará. It possesses morphological marker gene of the latter one which is ribbed fruit that is found only in cassava. Interspecific hybrids produced experimentally between M. glaziovii and cassava showed similar morphological markers. Exam of its ovules revealed formation of multiple embryos, an indicator of apomixis. Grafting it with common cassava was compatible, giving increased root size up to seven times.  相似文献   

16.
Apple (Malus?×?domestica Borkh.) trees, either abandoned or cared for, are common on the North American landscape. These trees can live for decades, and therefore represent a record of large- and small-scale agricultural practices through time. Here, we assessed the genetic diversity and identity of 330 unknown apple trees in northern Minnesota with 9 simple sequence repeat (SSR) markers. The unknown (not identified by cultivar name) trees were compared to >?1000 named cultivars in the U.S. Department of Agriculture Plant Genetic Resources Unit Malus collection and also to each other to identify repeated genotypes. Overall, the 330 unknown trees had high diversity (average He?=?0.75), and consisted of 264 unique genotypes. A total of 76 of the unknown trees were matched to 20 different named cultivars, and these cultivars were mainly derived from either the local breeding program at the University of Minnesota, or were Russian cultivars imported for horticulture in the northern US. This study demonstrates the importance of local breeding programs, and also the challenges associated with identifying clones in a genetically diverse crop like apple.  相似文献   

17.
Lotus creticus is a potentially important perennial legume for soil management in the Mediterranean climate. This plant is in focus of experimental research in different countries. The so-called Lotus creticus group is taxonomically problematic. Although some authors consider all members of the group as a single variable species, others segregate several species distinct from L. creticus, especially L. cytisoides. Recent morphological studies suggested that L. creticus and L. cytisoides are taxonomically distinct at specific level and not even closely related to each other. Two molecular phylogenetic studies published so far and based on one accession of L. creticus each gave conflicting results on relationships of this species. In this paper, sequences of nuclear ribosomal ITS (nrITS) are produced from multiple accessions of both L. creticus and L. cytisoides. Taxonomic identity of each accession has been tested using morphology. The new nrITS sequences are inserted in a data matrix containing a representative set of Lotus species covering all the geographical range and all major taxonomic groups of Lotus. Phylogenetic analysis of nrITS sequence data showed that L. creticus is related to L. assakensis and other species of the section Pedrosia while L. cytisoides is related to L. longisiliquosus and other species of the section Lotea. These results are important for establishing future germplasm collection, breeding and selection programs of perennial Lotus species.  相似文献   

18.
In 1970s it was thought that two species of ‘farro’, namely emmer (Triticum dicoccon Schrank) and einkorn (T. monococcum L.), were no longer present in Italy, but in 1981, some populations were discovered in a mountain area of the Appennino Sannita (central southern Italy). In 2006/2007 three monitoring missions were carried out to check the current situation of these ancient hulled wheats, specifically in the same areas where they were formerly collected. The same zones were also investigated by both paleo-ethnobotany and agrobiodiversity points of view. The results of this research have shown that nowadays einkorn is completely extinct while emmer is still cultivated in very few traditional farms, mainly as a fodder crop. A strong genetic erosion was detected also for emmer and several nowadays samples were contaminated by seeds of modern spelt (T. spelta L.) varieties. In the present study the causes of this genetic erosion and which safeguarding actions to be undertaken are discussed.  相似文献   

19.
A highly informative set of 16 microsatellite markers was used to fingerprint 695 apple accessions from eight Dutch collections. Among the total sample, 475 different genotypes were distinguished based on multi-locus microsatellite variation, revealing a potential redundancy within the total sample of 32%. The majority of redundancies were found between collections, rather than within collections. No single collection covered the total observed diversity well, as each collection consisted of about 50% of unique accessions. These findings reflected the fact that most collection holders focus on common Dutch varieties, as well as on region-specific diversity. Based on the diversity patterns observed, maintenance of genetic resources by a network of co-operating collection holders, rather than by collecting the total diversity in a single collection appears to be an efficient approach. Comparison of microsatellite and passport data showed that for many accessions the marker data did not provide support for the registered variety names. Verification of accessions showed that discrepancies between passport and molecular data were largely due to documentation and phenotypic determination errors. With the help of the marker data the varietal names of 45 accessions could be corrected. Microsatellite genotyping of apple appears to be an efficient tool in the management of collections and in variety identification. The development of a marker database was considered relevant as a reference instrument in variety identification and as a source of information about thus far unexplored diversity that could be of interest in the development of new apple varieties.  相似文献   

20.
Changes of gene expression played an important role in the evolution of plant allopolyploids. Frequency, time and type of the changes of gene expression between the first two self-pollinated generations (S1 and S2) of a synthesized allotetraploid Cucumis × hytivus Chen et Kirkbride and in its diploid parents was analyzed with cDNA-AFLP and reverse-Northern blot technique. Sequences similarity of genes involved in changed expression were also analyzed with BLAST package. The results from cDNA-AFLP analysis showed that 36 (3.37%) genes showed silencing (27) or activation (9) in allotetraploids. These changes initiated in S1 or S2 generation. The silenced/activated genes included rRNA and protein-coding genes. Further reverse-Northern blot analysis validated the results obtained. Thus four types of changes of gene expression were observed, including silencing of genes from both parents, maternal parent, paternal parent, and genes novel expression. The results indicate rapid changes in gene expression in early generations of C. × hytivus, which contributed to the evolution of this synthetic allotetraploid.  相似文献   

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