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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.
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   

3.
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   

4.
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   

5.
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   

6.
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   

7.
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   

8.
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   

9.
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   

10.
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   

11.
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   

12.
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   

13.
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   

14.

Purpose

Willow cultivation in soils heavily contaminated by risk elements is a challenging issue due to phytotoxic effects that restrict plant growth. Liming reduces the mobility of some risk elements in contaminated soils and therefore can be a suitable measure for contaminated soils but can also affect availability of nutrients for planted willows. We investigate how liming affects concentrations of macro, micro, and toxic elements in the organs of willows planted in contaminated soils.

Materials and methods

We established a 3-year pot experiment with Salix × smithiana planted in weakly acid and alkaline soils anthropogenically seriously contaminated by As, Cd, Pb, and Zn. Soils were both untreated and treated with two doses of lime and dolomite in the first year before planting. We determined biomass production, mortality, and the concentration of macro- and micronutrients and toxic elements in the willows’ aboveground organs.

Results and discussion

Lime application increased biomass production in both soils; dose of lime played an important role for its increase only in alkaline soil. Lime in a higher dose was incompatible with the vitality of just-planted willows in both soils. Doses of dolomite significantly affected the biomass production and mortality of willows, where lower doses caused a permanent decrease of biomass production and mortality in weakly acid soil. The toxicity of Cd and Zn in leaves was recorded in both untreated soils; the latent deficiency of P and deficiency of Fe in leaves was only recorded in weakly acid untreated soil.

Conclusions

Lime application irrespective of dose with foliar Fe application seemed to be the most suitable measure for increasing biomass production and decreasing toxic elements, especially Cd and Zn, without decreasing the macro- and micronutrients in the aboveground organs of willows in weakly acid soil. In alkaline soil, only higher doses of lime had a positive effect on the studied parameters. Dolomite application is not a suitable measure for planting willows in both contaminated soils. Dolomite in a lower dose impairs the growth of willows in weakly acid soil.
  相似文献   

15.
Genetic diversity of a set of introgression lines of Triticum aestivum L./T. polonicum L. with long glume and T. petropavlovskyi Udacz. et Migusch. were analyzed by Amplified Fragments Length Polymorphism (AFLP). Small-scale bulk breeding method was applied throughout until F6 generation to develop the introgression lines. Thirty-eight hexapolid F7 plants with long glume phenotype and their parents were subjected to AFLP analysis by four primer combinations. A total of 47 polymorphic loci were detected between the parents, 15 of them were introgressed across the 38 lines. It was hypothesized that approximately 50% of A or B genomes associated polymorphic loci were introgressed. The variation of introgression lines was limited within the diversity between their parents, T. aestivum L. cv. Novosibirskaya 67 (N67) and T. polonicum L. cv. IC12196. N67 was closer to 38 introgression lines than that of IC12196. The UPGMA cluster and principal coordinate analysis (PCO) grouping showed 0.84 to 0.98 similarity values between N67 and the introgression lines. Eleven T. petropavlovskyi accessions were distinguished from introgression lines with UPGMA clusters and PCO groupings, and T. petropavlovskyi was located between the introgressions lines and IC12196. Several introgression lines resembled with T. petropavlovskyi for awning and glume length. The genetic variation among 38 introgression lines was much wider than that of T. petropavlovskyi. We concluded that T. petropavlovskyi was established by intensive selection of hybrid between T. aestivum/T. polonicum.  相似文献   

16.
The internal transcribed spacer (ITS) region was employed to analyze phylogeny of 20 populations, including the local cultivar “Nanjiang”, belonging to 7 species of Lonicera L. 20 ITS sequences that we obtained range from 614 to 618 bp, and the G+C content was higher than 60% with the average value 63.5%. The sequences of 5.8S nrDNA was highly conservative in both length and component, while ITS2 had more variation than ITS1 in sequence component and length. For the ITS complete sequence, the mutation and information sites were 139 and 117 with the content of 22.38 and 18.84%, respectively. The dendrogram analysed by neighbor-joining method showed that “Nanjiang” and Lonicera similis Hemsl. comprised a same cluster with a higher bootstrap support, indicating “Nanjiang” would be a variation or subspecies of L. similis Hemsl. The results of antibacterial activity test and active compounds identification showed that “Nanjiang” had the best antibacterial activity and the highest yield of chlorogenic acid, the active component of Flos Lonicerae, in the six species of Lonicera L.  相似文献   

17.
Triploid onion, Allium × cornutum Clementi ex Visiani, 1842 (2n = 3x = 24), a vegetatively reproduced garden crop, possess a complex triparental genome organization with three putative parental species, A. cepa L., A. pskemense B. Fedtsch., and A. roylei Stearn. Two of its most studied clones are the Croatian ‘Ljutika’ and the Indian ‘Pran’, which are genetically highly similar. Earlier studies have shown that ‘Pran’ possesses some molecular markers in the chloroplast DNA (cpDNA) identical to those of the unique male-sterile (S) cytoplasm, used for onion breeding. To find out whether ‘Ljutika’ also possesses a S-type of cytoplasm, we analyzed several cpDNA and mitochondrial (mtDNA) molecular markers. The PCR amplification and RFLP analysis of the chloroplast genes accD, atpF, petB and the mitochondrial gene cob, as well as the sequence analysis of the chloroplast matK and atpB-rbcL regions showed that ‘Ljutika’ possesses the male-sterile S-type of cytoplasm. The phylogenetic analysis of the matK and atpB-rbcL sequences of A. × cornutum, its parental species and other Allium species of the section Cepa showed that none of the analyzed species had the identical type of cpDNA as A. × cornutum. Results also suggested that A. pskemense can be excluded as a donor of the S-cytoplasm and a female parent, whereas cpDNA of A. roylei, although not identical to S-cytoplasm, possessed many polymorphisms of S-type. Fluorescent in situ hybridization, using fluorescently labelled parental genomic DNAs as probes in combination with fluorescently labelled 5S and 35S rDNAs enabled simultaneous visualization of the three genomes during meiosis and confirmed their homeologus intergenomic pairing.  相似文献   

18.
The Bavarian Turnip (Bayerische Rübe, Brassica rapa L. em. Metzg. var. rapa) is a nearly lost crop today. Until 1900, this local variety was commonly grown in Bavaria for human consumption. The special and very distinct characters of this variety in comparison with recent breeds are preferred by the farmers families and assured the persistence and survival of this turnip in situ (on farm). In the region of Dachau and Freising, located north of Munich, only four farms are known, where this old crop is still grown and maintained. Urgent measures have to be taken to safe this cultural relict for future generations.  相似文献   

19.
Genetic consequences of silvicultural management of Leucaena esculenta subsp. esculenta were analyzed from eight allozyme loci in half-sib families of one wild and one managed in situ (selectively cleared) population from La Montaña de Guerrero region, Central Mexico. A reference sample (including wild, feral and cultivated individual plants) from the states of Morelos, Puebla and Guerrero, Mexico was also analyzed. Genetic variation, population structure and mating system were analyzed. All loci showed high variation (75–87.5% polymorphic loci at 95% level; 2.4–2.8 mean number of alleles per locus). All progenies showed heterozygous deficiency, but both wild and managed parental inbreeding coefficients were negative, suggesting heterosis. Progenies of managed populations differed from those of the wild and reference samples (Nei’s unbiased identities 0.874–0.934). Biparental inbreeding is suggested by Wright’s-statistics ( f = 0.313), and by outcrossing rate estimates: tm = 0.644 (SE 0.094), and 0.645 (SE 0.193); ts = 0.576 (SE 0.189), and 0.523 (SE 0.182), for managed and wild samples respectively. Population differentiation is significant (Θ = 0.210). The species is self-incompatible and deviations from the mixed mating model were found. Indirect estimates of products of effective population size (Ne) by the proportion of migrants (Nm) were moderate, as were the N evalues. Variation due to ecotypic differentiation (related to altitude), prolonged artificial selection, and introduction from other areas is supported. A model of domestication of seed-propagated trees is suggested, based on extensive and in situ selection of locally adapted populations, and their diffusion to other areas.  相似文献   

20.
Species that belong to the genus Triticum L. and the genetically related Aegilops L. genus are important genetic and economic resources because they have an evolutionary relationship with the two main agricultural crops T. aestivum (bread wheat) and T. durum (durum wheat). Therefore, it is important to understand the genetic relationships among the cultivated wheat species and their wild relatives. The latter have a great role in the improvement of cultivated wheat. Molecular markers are the best choice and most reliable means to study these relationships accurately. In this study, we compared the efficiency of the biochemical methods A–PAGE and SDS–PAGE on seed storage proteins and the molecular methods RAPDs and ISSRs to explore the genetic relationships among seven species of Triticum and 20 Aegilops species. Three phylogenetic trees obtained in this study were compared with available classifications and phylogenetic trees constructed earlier for these species. It was noted that the tree based on ISSRs data was the most congruent with those classification and trees. This may be attributed to the fact that ISSRs is more specific, and therefore more reliable. This study is the first to study genetic relationships among all species studied here using biochemical and molecular techniques.  相似文献   

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