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51.
The Fagopyrum cymosum complex is a group of wild perennial buckwheats which includes the diploid species F. megaspartanium Q. F. Chen and F. pilus Q. F. Chen as well as the allotetraploid species F. cymosum (Trev.) Meisn. The flavonoid content in leaves and inflorescences of the accessions of the F. cymosum complex native to Guizhou, Yunnan, Sichuan, Hunan, Hubei, and Tibet has been studied by means of the spectrophotometry and high-performance liquid chromatography. The results showed that there are significant differences of flavonoid content among different species, different accessions and different plants. The average flavonoid content of leaves of F. megaspartanium is higher than that of F. pilus and of F. cymosum. The average flavonoid content of inflorescences of F. megaspartanium is higher than that of F. pilus. The results also showed that the flavonoid content in inflorescences was significantly higher than that in leaves, and that they have positive relationships to each other. There is a significant difference of rutin content between leaves and inflorescences, but there is no significant relationship to each other. There is also no significant relationship between leaf rutin contents and leaf flavonoid contents, but significant positive relationship between inflorescence rutin contents and inflorescence flavonoid contents.  相似文献   
52.
X. L. An  X. H. Li  X. J. Xiong  Y. M. Yan    Y. Z. Zhang    L. Y. Gao    A. L.Wang    K. Wang    F. J. Zeller    S. L. K. Hsam 《Plant Breeding》2009,128(1):41-45
A new x-type HMW glutenin subunit, designated as 1Dx1.6t from Aegilops tauschii was identified and characterized by SDS-PAGE and MALDI-TOF-MS. This subunit is located between 1Dx2 and 1Dx1.5t and possesses a molecular mass ( M r) of 88565.8 Da. Its complete coding sequence was amplified via allele-specific PCR (AS-PCR), and the amplified product was cloned and sequenced. The authenticity of the cloned 1Dx1.6 t gene was confirmed by successful expression of its open reading frame in Escherichia coli. The molecular characterization of 1Dx1.6 t gene showed that its coding region consisted of 2541 bp encoding a polypeptide of 845 amino acid residues. Sequence comparison to previously characterized 1Dx1.5t subunit which is related to good dough quality of bread wheat indicated that the 1Dx1.6t subunit displayed high homology, but possesses 14 residue substitutions and a nonapeptide insertion. A total of 12 single-nucleotide polymorphisms (1 per 212 bp) was identified in the 1Dx1.6 t allele (11 in repetitive domain and 1 in the C-terminal domain), which could facilitate the design of AS-PCR markers.  相似文献   
53.
  • ? The development of truffles in the soil is not well understood. It is not known if a direct transfer of carbohydrates takes place between the host tree and the developing ascocarps through ectomycorrhizal structures or whether sporophores become independent from their hosts after several weeks or months and are able to use dead host tissues or soil organic matter as carbon (C) and nitrogen (N) sources.
  • ? To study saprophytic or symbiotic capacities of truffle ascocarps the natural abundance of 15N and 13C in foliage, wood, fine roots, mycorrhizae, fungal sporophores and soil were determined in a truffle orchard.
  • ? The processes of carbon and nitrogen allocation remained unchanged during the entire period of ascocarp development of Tuber melanosporum. From 13C and 15N natural abundance measurements, T. melanosporum, T. brumale and T. rufum did not exhibit saprotophic strategy during ascocarp development, which is contradictory to common statements found in handbooks regarding truffle cultivation.
  •   相似文献   
    54.
    Differentiation between resident mature lymphocyte populations and small cell lymphoma cannot be made by cytological review alone and remains challenging in histopathological review. These cases warrant application of complementary tools like PCR‐based immunoglobulin (IG) and T‐cell receptor (TCR) clonality testing for confirmation. In this prospective study, diagnostic sensitivity and specificity of different primer sets for routine diagnosis of feline TCR gamma (TCRG) and complete IG heavy chain (IGH) gene rearrangements were assessed. Fine needle aspirates from 20 feline lymphoma cases and lymph node material from 10 cats without hematopoietic neoplasia were subjected to clonality testing. Feline lymphoma cell lines and previously confirmed patient material served as positive control. Detection limits for clonal populations within a polyclonal background was 90% for B‐cells and 50% for T‐cells. Diagnostic sensitivity and specificity of the clonality assay were 70% and 90%. Overall diagnostic accuracy was 77%, positive predictive value 93% and negative predictive value 60%.  相似文献   
    55.
    A serological survey of Rift Valley fever was carried out in sheep in C?te-d'Ivoire. Thousand and fifty one seras collected between 1988 and 1990 in the South of the country were tested for IgG and IgM by ELISA with two objectives: determining the incidence of the Rift Valley fever and analysing the role of this virus in reproductive failure and abortion. The incidence rate was 6.85%. No difference was found between the three different geographic areas nor between the three years of the survey. Antibody prevalence increased significantly with age. The Rift Valley fever must be considered as enzootic in C?te-d'Ivoire. A significant relationship was found between positivity and abortion in ewes. Thus, the economic impact of Rift Valley fever has to be studied. The presence of antibodies in young animals aged from 6 months to 1 year, showed a recent activity of the virus; a permanent epidemio-surveillance of the Rift Valley fever in C?te-d'Ivoire is needed, because of the potential risk for human population in contact with the animals.  相似文献   
    56.
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    58.

    Context

    Scale is the lens that focuses ecological relationships. Organisms select habitat at multiple hierarchical levels and at different spatial and/or temporal scales within each level. Failure to properly address scale dependence can result in incorrect inferences in multi-scale habitat selection modeling studies.

    Objectives

    Our goals in this review are to describe the conceptual origins of multi-scale habitat selection modeling, evaluate the current state-of-the-science, and suggest ways forward to improve analysis of scale-dependent habitat selection.

    Methods

    We reviewed more than 800 papers on habitat selection from 23 major ecological journals published between 2009 and 2014 and recorded a number of characteristics, such as whether they addressed habitat selection at multiple scales, what attributes of scale were evaluated, and what analytical methods were utilized.

    Results

    Our results show that despite widespread recognition of the importance of multi-scale analyses of habitat relationships, a large majority of published habitat ecology papers do not address multiple spatial or temporal scales. We also found that scale optimization, which is critical to assess scale dependence, is done in less than 5 % of all habitat selection modeling papers and less than 25 % of papers that address “multi-scale” habitat analysis broadly defined.

    Conclusions

    Our review confirms the existence of a powerful conceptual foundation for multi-scale habitat selection modeling, but that the majority of studies on wildlife habitat are still not adopting multi-scale frameworks. Most importantly, our review points to the need for wider adoption of a formal scale optimization of organism response to environmental variables.
      相似文献   
    59.
    S. L. K. Hsam    V. Mohler    L. Hartl    G. Wenzel  F. J. Zeller 《Plant Breeding》2000,119(1):87-89
    Powdery mildew and leaf rust resistance genes on the 1RS arm of the T1BL·1RS translocated chromosome were mapped in relation to the Sec‐1 locus and AFLP and restriction fragment length polymorphism markers, respectively, employing segregating F3 populations. Integration of molecular markers indicated that Pm17 lies between the Lr26 and Sec‐1 loci, with both resistance genes allocated distally to the Sec‐1 locus in the satellite of the 1RS arm.  相似文献   
    60.
    一些小麦1B/1R易位系品质基因多样性分析   总被引:1,自引:0,他引:1  
    利用SDS-PAGE和A-A-PAGE分析了38份小麦1B/1R易位系Glu-1、Glu-3、Gli-1位点基因组成。结果表明,小麦1B/1R易位系中品质基因多样性降低,Glu-1、Glu-3编码的高、低分子量谷蛋白亚基种类减少,Glu-B1位点含有的优质亚基比例明显下降,Gli-1位点编码的醇溶蛋白比例增加,导致劣质。因此对于抗病品种品质改良要着重于改变其遗传组成尤其是Glu-1、Glu-3、Gli-1位点基因组成,尽可能打破Glu-3、Gli-1位点基因连锁关系,淘汰Glu-3位点基因的j,导入一些优良的品质基因。  相似文献   
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