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1.
We studied some features of the development of self-fertile 42-chromosome lines on the base of self-pollination progeny of 46-chromosome plants obtained by backcrossing of barley-wheat hybrids Hordeum marinum subsp. gussoneanum Hudson (= H. geniculatum All.) (2n = 28) × Triticum aestivum L. (2n = 42). The stabilization of karyotypes, resulting in 42-chromosome plants of the wheat type was generally completed by generation BC1F10. The plants of all self-pollination progenies, including BC1F10, showed some phenotypic traits characteristic of wild barley. Plants of BC1F10 with the chromosome sets 2n = 42 and 2n = 42 + t were analyzed by RAPD with a set of 115 primers. Fragments of the wild barley genome were detected in RAPD patterns with 19 primers. Cross-hybridization confirmed that these fragments belonged to the wild barley genome. We raised four phenotypically different 42-chromosome lines from grains obtained from plants of generation BC1F10, and these lines proved to be cytogenetically stable and self-fertile when grown in the field.  相似文献   

2.
Genomic in situ hybridization (GISH) has been used to study characteristics of the formation of alloplasmic lines detected among self-pollinated backcrossed progeny (BC1F5–BC1F8) of barley–wheat amphiploids [Hordeum geniculatum All. (2n = 28) × Triticum aestivum L. (2n = 42)] (2n = 70). The chromosome material of the wild barley H. geniculatum has been shown to contribute to these lines. For example, fifth-generation plants (BC1F5) had genotypes (2n= 42w + 2g), (2n = 42w + 1g + 1tg), and (2n = 41w + 1g), where w is common wheat chromosomes, g is barley (H. geniculatum) chromosomes, and tg is the telocentric chromosome of wild barley. Beginning from theBC1F6 generation, alloplasmic telocentric addition lines (2n= 42 + 2tg) and (2n = 42 + 1tg) appear. This lines has been found cytogenetically unstable. The progeny of each of these cytological types include not only the (2n= 42 + 2tg) and (2n = 42 + 1tg) addition plants, but also plants with the monosomic (2n = 41 + 1tg) and the disomic (2n = 40 + 2tg) substitutions, as well as the (2n = 41 + 2tg) plants, which lack one wheat chromosome and have two telocentric barley chromosomes. It has been demonstrated that the selection for well-filled grains favors the segregation of telocentric addition lines (2n = 42 + 2tg) and (2n = 42 + 1tg).  相似文献   

3.
The backcross progenies of the barley–wheat hybrids Hordeum vulgare L. (2n = 14) × Triticum aestivum L. (2n= 42) and two alloplasmic lines derived from them were studied using microsatellite markers of barley and wheat. The F1 hybrids and first backcross plants BC1 contained the genetic material of both cultivated barley and the cultivars of common wheat involved in developing of these hybrid genotypes. The genomes of BC3, BC4, and alloplasmic lines contained no microsatellite markers of the cultivated barley, whereas chromosomes of each homeologous group of common wheat were identified. In chromosomes of backcross progenies BC3, BC4, and alloplasmic lines yielded by backcrosses of hybrids and various common wheat cultivars, microsatellite markers of the parental wheat cultivars were shown to undergo recombination.  相似文献   

4.
5.
《Inorganica chimica acta》2001,312(1-2):221-225
[(CN)5PtTl(CN)n]n (n=0–3, complexes IIV) have been studied computationally using quasi-relativistic gradient-corrected density functional theory. Good agreement is obtained with previous EXAFS and Raman data for complexes IIIV, but calculations significantly overestimate the PtTl bond length and underestimate ν(PtTl) for complex I. The addition of co-ordinating water molecules to the thallium atom in complexes IIII has little effect on complexes II and III, but significantly shortens the PtTl bond in complex I, bringing it into excellent agreement with experiment. The bond length shortening is traced to intramolecular hydrogen bonding. The total molecular bonding energies of hydrated I and I′ (in which the axial ligands on the thallium and platinum atoms are interchanged) are found to be very similar to one another, suggesting that complex I might exist as a mixture of isomers in solution.  相似文献   

6.
《Inorganica chimica acta》1988,148(2):233-240
The complexes CodptX3 and [Codpt(H2O)X2]ClO4 (X = Cl, Br; dpt = dipropylenetriamine = NH(CH2CH2CH2NH2)2) have been prepared and characterized. Rate constants (s−1) for aqueous solution at 25 °C and μ = 0.5 M (NaClO4), for the acid-independent sequential ractions.
have been measured spectrophotometrically. For X = Cl: k1 ⋍ 2 × 10−2, k2 = 1.7 × 10−4 and k3 = 4.8 × 10−6, and for X = Br: k1 ⋍ 2 × 10−2, k2 = 5.25 × 10−4 and k3 = 2.5 × 10−5 The primary equation was found to be acid independent, while the secondary and tertiary aquations were acid-inhibited reactions. For the second step, the rate of the reaction was given by the rate equation
where Ct is the complex concentration in the aqua-and hydroxodihalo species, k2 is the rate constant for the acid-dependent pathway and Ka is the equilibrium constant between the hydroxo and aqua complex ions. The activation parameters were evaluated, for X = Cl: ΔH2 = 106.3 ± 0.4 kJ mol−1 and ΔS2 = 40.2 ± 1.7 J K−1 mol, and for X = Br: ΔH2 = 91.6 ± 0.4 kJ mol−1 and ΔS2 = 0.4 ± 1.7 J K−1 mol−1. The results are discussed and detailed comparisons of the reactivities of these complexes with other haloaminecobalt(III) species are presented.  相似文献   

7.
We studied common wheat alloplasmic lines differing in fertility traits, which had been obtained from the backcross progeny of barley—wheat hybrids Hordeum vulgare L. (2n = 14) × Triticum aestivum L. (2n = 42), using molecular analysis and chromosome C-banding. It was found that the nuclei of all alloplasmic lines studied, regardless of their fertility traits, contained only the common wheat chromosomes (2n = 42). The formation of line L-79(10)(3)F6, stable for self-fertility, from line L-79(10)F3 was accompanied by changes of the proportions of simple sequence repeats of the parental common wheat varieties in the nuclear genome. The presence of barley genome fragments in line accessions with incomplete self-fertility was shown by RAPD. Heteroplasmy for mitochondrial genome loci was detected in these lines with the use of primers specific to the tMet-18S-5S repeat of mitochondrial ribosomal genes.Translated from Genetika, Vol. 40, No. 12, 2004, pp. 1668–1677.Original Russian Text Copyright © 2004 by Bildanova, Badaeva, Pershina, Salina.  相似文献   

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10.
Tabanus pseudonebulosus, new species, is described based on 217 female specimens and 5 males collected in Venezuela (Guarico, Aguaio, Santa Elena, and Palmarito) and in Brazil (Parcí: Santana do Araguaia, Serra das Andorinhas in S?o Geraldo do Araguaia, Serra Norte Carajás and Gorotire; Amazonas: Canutama; Mato Grosso do Sul: Corumbá), mostly in open vegetation, scrub forest and in rocky environments. Observed intraspecific variation in the specimens is presented and related to collection localities, and morphological differences are diagnosed in relation to the similar species Tabanus nebulosus DeGeer 1776 and T. importunus Wiedemann 1828. Morphometrical data and indices for specimens in different localities are provided. Drawings and photo of the new species are presented.  相似文献   

11.
A new high yielding synthesis of the seven-coordinate complexes [MI2(CO)3{Ph2P(CH2)nPPh2}] (M = Mo and W; n = 1–6) is described. The procedure involves reacting the complexes [MI2(CO)3(NCMe)2] in CH2Cl2 with an equimolar amount of the bidentate phosphorus ligand. The low temperature (−70 °C) 13C NMR spectra of the complexes [Wl2(CO)3{Ph2P(CH2)nPPh2}] (n = 3 and 5) indicates that the geometry is capped octahedral with a carbonyl ligand in the unique capping position.  相似文献   

12.
We studied hydrated calcium oxalate and its ions at the restricted Hartree–Fock RHF/6-31G* level of theory. Performing a configurational search seems to improve the fit of the HF/6-31G* level to experimental data. The first solvation shell of calcium oxalate contains 13 water molecules, while the first solvation shell of oxalate ion is formed by 14 water molecules. The first solvation shell of Ca(II) is formed by six water molecules, while the second shell contains five. At 298.15 K, we estimate the asymptotic limits (infinite dilution) of the total standard enthalpies of hydration for Ca(II), oxalate ion and calcium oxalate as ?480.78, –302.78 and –312.73 kcal mol?1, resp. The dissociation of hydrated calcium oxalate is an endothermic process with an asymptotic limit of +470.84 kcal mol?1.
Figure
CaC2O4(H2O)16 and C2O4 2-(H2O)14  相似文献   

13.
Systematic Parasitology - Previous phylogenetic analyses of the Acanthocephala have demonstrated that the families Rhadinorhynchidae Lühe, 1912 and Transvenidae Pichelin & Cribb, 2001...  相似文献   

14.
Cacatuocotyle paranaensis n. sp. (Dactylogyridae, Ancyrocephalinae) is described from the gills of the characid fishes Characidium lanei Travassos and C. pterostictum Gomes collected from two streams on the coast of the State of Paraná, Brazil. Cacatuocotyle n. g. is proposed for species possessing a single cephalic lobe (terminal), one pair of head organs, a convex haptor with thickened muscular anterior margins, one anchor-bar complex (ventral), seven pairs of ventral hooks (one pair associated with the anchor shafts; one central pair anterior to the bar; five submarginal bilateral pairs) and a sinistral vaginal aperture.  相似文献   

15.
Abundance and degree of dispersion of genomic d(GA) n ·d(TC) n sequences   总被引:5,自引:0,他引:5  
Summary The abundance of d(GA) n ·d(TC) n tracts was determined in genomes of rodents and primates. Dot blot hybridization assays revealed that such tracts constitute 0.40%, 0.30%, and 0.40%, respectively, of the rat, hamster, and mouse genomes, but only 0.07% and 0.05% of the human and monkey genomes. A plaque hybridization assay of rat and human genomic libraries showed that 37% and 16%, respectively, of the recombinant phages in these libraries contain d(GA) n ·d(TC) n tracts. A survey of sequences stored in the GenBank data bank showed that a significant fraction of the stored rodent genes (about 2.0%) contain long d(GA) n ·d(TC) n tracts (n> 30) with <10% mismatching. The primate genes contain only shorter tracts (n<15) with <10% mismatching. In addition, the rodent and the primate genes contain tracts with larger degrees of mismatching. The chicken, which represents an entirely different branch of the evolutionary tree, was found to be as low in d(GA) n ·d(TC) n tracts as the primates. It is suggested that a common ancestor of the rodents has acquired the ability to amplify d(GA) n ·d(TC) n tracts.  相似文献   

16.
From the Buschmann-Klippe-Formation, mainly considered as Late Precambrian in age until now, the ArchaeocyathaBuschmannia roeringi, n. gen., n. sp. is described. Based on this discovery, an Early Cambrian age for the Nama-group is assumed.  相似文献   

17.
Immunoglobulin (Ig) allotype typing is usually performed with serological methods based on hemagglutination inhibition. The recent development of molecular techniques has allowed the molecular typing of several Ig markers. The hinge, CH2, and CH3 domains of the G2 gene from six unrelated individuals (three G2m(n+) and three G2m(n–)) were amplified and cloned to establish the molecular basis of the G2m n+ and G2m n–. Comparison of the allele sequences revealed three changes: two (codons 308 and 437) are silent exonic substitutions, one is a G to A transition corresponding to an amino acid difference in position 282: Val (GTG) in G2m n–, Met (ATG) in G2m n+. These substitutions were identified via two approaches: 282 polymorphism, after digestion of a specific polymerase chain reaction product with Nla III followed by acrylamide electrophoresis; 308 and 437, by a dot-blot technique using allele-specific oligonucleotides. These molecular typing results correspond exactly to those obtained serologically; moreover, the three substitutions defining the G2m n+ and G2m n– alleles are always associated in a strict linkage disequilibrium.The nucleotide sequence data reported in this paper have been submitted to the EMBL nucleotide sequence database and have been assigned the accession numbers Z49801 and Z49802  相似文献   

18.
《Carbohydrate research》1998,310(4):229-238
Eight positional isomers of 61,6m-di-O-α-d-mannopyranosyl-cyclomaltooctaose (γCD) (m=2–5) and 6-O-α-(n-O-α-d-mannopyranosyl)-d-mannopyranosyl-γCD (n=2, 3, 4, and 6) in a mixture of products from γCD and d-mannose by condensation reaction of α-mannosidase from jack bean were isolated by HPLC. The structures of four isomers of 6-O-α-(n-O-α-d-mannopyranosyl)-d-mannopyranosyl-γCD were elucidated by NMR spectroscopy. On the other hand, four positional isomers of 61,6m-di-O-α-d-mannopyranosyl-γCD were determined by LC–MS analysis of degree of polymerization of the branched oligosaccharides produced by enzymatic degradation with bacterial saccharifying α-amylase (BSA), and combination of BSA and glucoamylase. Similarly cyclomaltodextrin glucanotransferase also digested these isomers.  相似文献   

19.
卢宝荣  杨俊良   《广西植物》1991,11(3):231-239
本文对缘毛鹅观草(Roegneria pendulina)、鹅观草(R.tsukushiensis var.transiens)及其人工合成杂种F1、双二倍体进行了细胞学,育性等的分析和研究。结果表明双亲的减数分裂,花粉育性和结实性均正常,杂种F1的减数分裂不规则且完全不育;当代双二倍体的染色体数目为70,其减数分裂构型为:6.04 Ⅰ+26.21 Ⅱ+1.52 Ⅲ+1.59 Ⅳ+0.02 Ⅴ:第二代双二倍体的染色体数目为70,个别植株为69,减数分裂构型分别为:4.16 Ⅰ+27.33 Ⅱ+0.50 Ⅲ+2.16 Ⅳ和4.79 Ⅰ26.26 Ⅱ+1.13 Ⅲ+2.13 Ⅳ。与期望染色体配对模式相比,双二倍体中二价体出现的频率有明显增大的趋势。在减数分裂AⅠ和AⅡ分别观察到数目不定的落后单价体,大部份的四分体中出现了微核。双二倍体的育性得到了很大程度的恢复,其花粉可染色性及结实率分别为54.4%和64.0%。  相似文献   

20.
卢宝荣  杨俊良   《广西植物》1991,(3):231-239
本文对缘毛鹅观草(Roegneria pendulina)、鹅观草(R.tsukushiensis var.transiens)及其人工合成杂种F_1、双二倍体进行了细胞学,育性等的分析和研究。结果表明双亲的减数分裂,花粉育性和结实性均正常,杂种F_1的减数分裂不规则且完全不育;当代双二倍体的染色体数目为70,其减数分裂构型为:6.04 Ⅰ+26.21 Ⅱ+1.52 Ⅲ+1.59 Ⅳ+0.02 Ⅴ:第二代双二倍体的染色体数目为70,个别植株为69,减数分裂构型分别为:4.16 Ⅰ+27.33 Ⅱ+0.50 Ⅲ+2.16 Ⅳ和4.79 Ⅰ26.26 Ⅱ+1.13 Ⅲ+2.13 Ⅳ。与期望染色体配对模式相比,双二倍体中二价体出现的频率有明显增大的趋势。在减数分裂AⅠ和AⅡ分别观察到数目不定的落后单价体,大部份的四分体中出现了微核。双二倍体的育性得到了很大程度的恢复,其花粉可染色性及结实率分别为54.4%和64.0%。  相似文献   

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