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971.
[Objective] The aim of experiment was to provide a new germplasm for wheat breeding by further using desirable genes in 2V chromosome of Haynaldia villosa.[Method] Through hybridization between common wheat(Triticum aestivum)-Haynaldia villosa disomic substitution line and common wheat Nonglin26-3C chromosome of Aegilops triuncialis disomic addition line,the analysis methods such as chromosome C-banding,genomic in situ hybridization and molecular marker technique were comprehensively applied and combined characters investigation.[Result] The wheat-Haynaldia villosa translocation line(T6BS·6BL-2VS)was selected from hybrid progenies to conduct characters investigation,which found some bristles on glume ridge of T6BS·6BL-2VS.[Conclusion] The translocation line induced by gametocidal chromosome was a small segment translocation line and the gene of bristle on glume ridge of Haynaldia villosa was located between the middle and the terminal of 2VS.  相似文献   
972.
刘金山  王有武  高山  江卫 《种子》2012,31(6):4-9
目的:研究陆海杂交棉新陆中31号叶绿素荧光参数及生理动态变化规律,为陆海杂交棉栽培管理、高产机理研究提供参考。方法:以新陆中31号、新海21号、中棉49号为试验材料,在棉花整个生育期,研究叶绿素荧光参数、可溶性糖、可溶性蛋白以及POD活性和CAT活性的变化。结果:在整个生育期,参试材料的Fv/Fm、Fv/Fo、qP、Yield和ETR、可溶性糖含量、可溶性蛋白含量和POD酶和CAT酶活性基本上呈现出相同的变化趋势,即随着生育期变化呈现出先增高后降低的趋势,总体上表现为盛花期最高,之后逐渐开始降低,而qN值的变化则不同。另外,在相同条件下,新陆中31号的Fv/Fm,Fv/Fo、qP、可溶性糖含量、可溶性蛋白含量、POD酶和CAT活性总是高于两个常规棉对照品种,说明在同等栽培管理条件下,该品种清除活性氧的能力较高,属于典型的高光效品种。结论:在相同栽培条件下,叶绿素荧光参数、可溶性糖含量、可溶性蛋白含量、POD酶和CAT酶活性的变化与基因型之间存在着密切相关,其中陆海杂交棉新陆中31号清除活性氧的能力较高。  相似文献   
973.
974.
To study the influence of genes from Thinopyrum intermedium on traits affecting the bread‐making quality of wheat, two derivatives from a putative disomic addition line in cultivar ‘Vilmorin 27’ were used in cytological, biochemical and molecular characterization. Cytological analysis suggested that one of the derivatives (Line‐1) had a terminal deletion involving the long arm of chromosome 1D (2n = 42, Del‐1DL”), and the other (Line‐2) was a conventional addition line, but also carried the same deletion on chromosome 1D (2n = 44, Thi”+Del‐1DL”). Amplification and sequencing of high‐molecular‐weight glutenin subunit (HMW‐GS) genes coded by the Th. intermedium chromosome in Line‐2 indicated the presence of one x‐type with an extra cysteine and four (rather than one) unique y‐type genes. Rheological studies of Line‐1 showed significantly lower dough strength compared to ‘Vilmorin 27’, confirming the recognized role of Glu‐1D coded HMW‐GSs. Line‐2 showed significantly higher dough strength compared to the background cultivar, indicating a significant potential of Th. intermedium for improvement of bread‐making quality in wheat.  相似文献   
975.
Distinct expression of GnRH genes in the red seabream brain   总被引:1,自引:0,他引:1  
This paper reports the molecular cloning of a cDNA encoding the precursor of seabream gonadotropin-releasing hormone (prepro-sbGnRH) and the localization of salmon GnRH (sGnRH) and seabream GnRH (sbGnRH) expressing neurons in the brain of the red seabream (Pagrus major). The cloned prepro-sbGnRH cDNA has a 285 bps open reading frame encoding a 23 amino acid signal peptide, a 10 amino acid sbGnRH, the cleavage site (Gly-Lys-Arg), and a 59 amino acid GnRH-associated peptide. The expression of sGnRH and sbGnRH peptides, and prepro-sGnRH and prepro-sbGnRH mRNA were studied using immunocytochemistry and non-radioactive in situ hybridization, respectively. We found cell bodies that reacted positively with both the sGnRH cRNA probe and anti-sGnRH serum, but not with the sbGnRH cRNA probe or anti-sbGnRH serum in the ganglion of the terminal nerve. Cell bodies that reacted positively with the sbGnRH cRNA probe, anti-sbGnRH serum, and anti-sGnRH serum, but negatively with the sGnRH cRNA probe were found in the preoptic area (POA). Immunocytochemistry showed that a distinct bundle of axons arises in the POA which projected to the pituitary gland. These results suggest that sbGnRH is the most relevant hypophysiotropic form of GnRH.  相似文献   
976.
甘蔗是非整倍性异源多倍体作物,遗传背景高度复杂,其细胞生物学研究难度大。近年分子标记技术以及原位杂交技术等快速发展使甘蔗细胞学研究也取得明显进展。本文主要围绕甘蔗核型、染色体行为、原位杂交技术在甘蔗上的应用展开综述,以期为高倍体植物细胞学研究提供参考。  相似文献   
977.
Nineteen cutaneous and mucocutaneous papillomas, as well as 29 oral and 25 non-oral squamous cell carcinomas of dogs were analyzed immunohistologically for the presence of papillomavirus (PV)-antigens. Canine oral papillomavirus (COPV)-DNA was detected in formalin-fixed, paraffin-embedded tissues by polymerase chain reaction (PCR) and non-radioactive in situ hybridization (ISH). Furthermore, the expression of the tumor suppressor protein p53 was investigated. PV-antigens were detectable in more than 50% of the oral and cutaneous papillomas, while no PV-antigens could be demonstrated in venereal papillomas. One squamous cell carcinoma was PV-antigen positive. Only two cutaneous papillomas of the head showed a strong p53-specific immunostaining, while overexpressed p53 was detectable in approximately 35% of all squamous cell carcinomas. It was possible to amplify fragments of the E6, E7 and L1 gene by polymerase chain reaction (PCR) from five of eight oral and from five of eight cutaneous papillomas as well as from three oral squamous cell carcinomas. Nine of 10 papillomas showed a strong nucleus-associated hybridization signal typical for COPV-DNA. In three squamous cell carcinomas COPV-DNA was located in nests of the epithelial tumor cells surrounding ‘horn pearls' or disseminated in the carcinoma tissue. These observations support the view that COPV may also induce non-oral papillomas in the dog and confirm the opinion that a progression of viral papillomas into carcinomas in dogs may occur.  相似文献   
978.
对落花生栽培种与野生种种间杂交之障碍加以剖析,并综述克服落花生种间杂交障碍方面的研究成果,提供落花生种间杂交时之参考。种间杂交子房柄培养的结果显示,利用MS+150mg/LCH+50mg/L抗坏血酸(ascorbicacid)培养基可促进五个杂交组合之子房膨大且发育成荚果;杂交种子经无菌播种均获得再生植株,经染色体鉴定结果为2n=3×=30的三倍体杂种,生长株型为类似野生种的分枝匍匐型。种间杂交未熟胚以添加TDZ之MS培养基可诱导多芽体。杂交F1之花药以MS+2,4-D培养基诱导愈合组织,再转移至添加NAA和BA之分化培养基中可形成芽体,在添加2,4-D和TDZ之分化培养基中则有胚状体产生。  相似文献   
979.
980.
In order to provide further evidence to prove that Ascaris suum Goeze,1782 and Ascaris lumbricoides Linnaeus,1758 are really different species in taxonomy,and to identity A.suum larval migrans-related genes for diagnosis and prevention use,A.suum genes that were differentialy expressed from the same gender of A.lumbricoides were enriched by subtracting the same expressed genes using suppression subtractive hybridization (SSH) assay.Specificity of the selectively enriched cDNA was verified by Southern blot analysis.The female A.suum specific cDNA library was then constructed and sequenced.Basic local alignment search tool (BLAST) analysis of female A.suum specific cDNA identified 6 specific ESTs with tentative functions related to larva migrans.This study provided further evidence for differentiating A.suum from A.lumbricoides.Mining for the detailed information and application of the 6 ESTs are worth being done in the future studies.  相似文献   
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