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
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
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
[(CN)5PtTl(CN)n]n− (n=0–3, complexes I–IV) have been studied computationally using quasi-relativistic gradient-corrected density functional theory. Good agreement is obtained with previous EXAFS and Raman data for complexes II–IV, but calculations significantly overestimate the PtTl bond length and underestimate ν(PtTl) for complex I. The addition of co-ordinating water molecules to the thallium atom in complexes I–III has little effect on complexes II and III, but significantly shortens the PtTl 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
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, k′2 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: ΔH≠2 = 106.3 ± 0.4 kJ mol−1 and ΔS≠2 = 40.2 ± 1.7 J K−1 mol−, and for X = Br: ΔH≠2 = 91.6 ± 0.4 kJ mol−1 and ΔS≠2 = 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
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
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
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.
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
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
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
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
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 G2mn+ and G2mn–. 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 G2mn–, Met (ATG) in G2mn+. 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 G2mn+ and G2mn– 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
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