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21.
Homoeological relationships between the f chromosome of Brassica rapa and the e chromosome of Brassica oleracea 总被引:1,自引:0,他引:1
Eight plants of the putative double monosomic addition line (DMAL, 2n= 20) were developed by crossing a monosomic chromosome addition line of radish [f(A)‐type monosomic addition line (MAL) (2n= 19)] carrying the f chromosome of Brassica rapa (2n= 20, AA) with another [e(C)‐type MAL (2n= 19)] having the echromosome of Brassica oleracea (2n= 18, CC). The homoeological relationships between the two alien chromosomes were investigated by morphological, cytogenetic and random amplified polymorphic DNA (RAPD) analysis. Seventeen morphological traits that were not present in the radish cv. ‘Shogoin’ were observed in both MALs and these traits were substantially exhibited in DMAL plants. At the first metaphase of pollen mother cells (PMCs), the two parental MALs showed a chromosome configuration of 9II +1I, demonstrating impossibility of recombination between the R and the added chromosomes. The DMALs formed 10II in approximately 73% of PMCs, with one bivalent showing loose pairing between two chromosomes differing in size. In an attempt to identify the two MALs by RAPD‐specific markers using 26 selected random primers, 13 and 20 bands were specific for the f(A)‐type and the e(C)‐type MALs, respectively; 12 bands were common to both MALs (26.7%). In conclusion, the f chromosome of B. rapa is homoeologous to the e chromosome of B. oleracea. The genetic domain (genes) for 17 morphological traits are linked to each homoeologous chromosome bearing 27% of the corresponding RAPD markers. 相似文献
22.
不同地貌类型区1∶25万比例尺DEM的建立方法 总被引:4,自引:1,他引:4
以在 3个不同地貌类型区的试验为例证 ,研究探讨建立栅格化 DEM的技术要点和技术方法 ,并对所建立 DEM的精度进行评价。研究结果表明 ,在平原区可以直接利用 Terlk层及水系要素建立 DEM;在山区 ,则首先需要进行构造地形结构线的预处理 ,而在黄土丘陵沟壑区 ,不仅需要构造地形结构线 ,而且需借用大比例尺的高程数据进行高程加密处理 ,以最大限度地减少地貌特征信息的损失 ,为区域水土流失的动态监测基础地理数据库的建立提供重要的技术方法 相似文献
23.
Haejeen Bang Dong Youn Cho Kil-Sun Yoo Moo-Kyoung Yoon Bhimanagouda S. Patil Sunggil Kim 《Euphytica》2011,179(3):439-449
In order to implement reliable marker-assisted selection systems for the restorer-of-fertility locus (Ms) in onions (Allium cepa L.), simple PCR-based codominant markers linked to the Ms locus were developed. Based on the EST probe sequences of previously reported RFLP markers, full-length genomic sequences
of the gene encoding putative oligopeptide transporter (OPT) was obtained by RACE. The first intron contained two 108 and
439-bp indel polymorphisms between the two Ms allele-linked OPT alleles. A simple PCR marker for OPT was developed by designing a primer pair on the flanking regions of
the 108-bp indel which is created by two tandem repeats. The second simple PCR marker was developed from the EST probe encoding
photosystem I subunit O (PsaO). Two 14 and 39-bp tandem repeats were identified from the 5′ upstream sequences of the PsaO-coding
gene, which were isolated by genome walking. Three different compositions of these tandem repeats were identified from diverse
onion germplasm. A primer set binding to the flanking sequence of these polymorphic repeats was used to amplify three different
marker haplotypes. The OPT marker was tightly linked to the Ms locus at a distance of 1.5 cM, but the analysis of the linkage relationship showed little linkage disequilibrium between
the marker and the Ms locus. Even so, these simple PCR markers are valuable tools for the marker-assisted selection of segregating individuals
in onion F1 hybrid breeding programs. 相似文献
24.
用常规分析、钾的容量强度(Q/I)关系和电超滤(EUF)等法研究了安徽烟区黄红壤、黄棕壤和砂姜黑土的供钾特性。结果表明:粘粒矿物以高岭石、水云母为主的黄红壤有较高的供钾强度及速效钾数量,但土壤的供钾潜力及钾位缓冲容量PBC~k较低,固钾能力弱。粘粒矿物以水云母、蒙脱石为主的黄棕壤及以蒙脱石、水云母为主的砂姜黑土的供钾特性与黄红壤相反,其中砂姜黑土除固钾能力高于黄棕壤外,其他供钾指标略低于黄棕壤。土壤的供钾特性对烟草的吸钾量及钾肥肥效有直接影响。 相似文献
25.
江苏省蚕豆种质资源丰富。本所通过农艺性状、抗病性、抗逆性鉴定和营养成份测定 ,对其种质作出评价 ,并对其中 7个品种进行重点评述和推荐。 相似文献
26.
采用生长速率法测定了美洲商陆Phytolacca amercana Roxb、姜黄Curcuma longa 2种中药植物多种溶剂提取物对玉米小斑病菌Helminthosporium maydis、棉花枯萎病菌Fusarium oxysporium、柑橘绿霉病菌Penicilliam digitatum和小麦纹枯病菌Rhizotonia cerealis 4种植物病原真菌的生物活性.结果表明,姜黄提取物对玉米小斑和小麦纹枯2种病原菌有较好的抑制作用,其中乙醚提取物对玉米小斑病菌抑制效果最好,其EC50为0.4688 g/L,石油醚提取物对小麦纹枯病菌抑制效果最好,其EC50为0.034 g/L.美洲商陆甲醇提取物对柑橘绿霉和小麦纹枯2种病原菌有较强的抑制作用,尤其是根、叶、果3部分的提取物.从甲醇提取物中分离得到美洲商陆总皂甙,生测结果表明美洲商陆总皂甙对柑橘绿霉病菌有很强的抑制作用,其EC50为0.2032 g/L. 相似文献
27.
黄邦华 《安徽农业大学学报》2004,(5):114-116
高职院校学生思想政治工作必须考虑高职学生的特点。文中认为,实现高职院校思想政治工作专业化是解决高职院校思想政治工作的有效途径。 相似文献
28.
在新的贸易形势下研究我国农产品的竞争力是一个不可忽视的重要课题。文中从我国柑橘国际竞争力的现状入手,分析了制约我国柑橘国际竞争力提高的主要原因,提出了提高我国柑橘国际竞争力的对策。 相似文献
29.
HU Bang XIE Shang-kui HUANG Mei-jin JIANG Li PENG Hui WANG Jian-ping REN Dong-lin WANG Lei 《园艺学报》2012,28(7):1213-1218
AIM: To investigate the expression of extracellular signal-regulated kinase 5 (ERK5) in primary colorectal cancer (CRC) and adjacent normal mucosa, and to analyze the relationship between ERK5 expression and clinicopathological parameters for exploring the functions of ERK5 in the occurrence and development of CRC. METHODS: The expression of ERK5 in carcinoma tissues and normal mucosa was examined by a set of tissue microarrays and the method of immunohistochemistry. The potential relationship between ERK5 expression and clinicopathological features was also analyzed. RESULTS: ERK5 expression was significantly higher in CRC tissues (134/338, 39.6%) than that in normal tissues (21/80, 26.2%; P<0.05). Overexpression of ERK5 in CRC tissues was significantly correlated with distant metastasis (P<0.05). However, no correlation between ERK5 expression and age at surgery, sex, tumor location, the depth of invasion, lymph node metastasis, TNM staging or differentiation grade was found (P>0.05). According to the Kaplan-Meier analysis, there is no significant difference in 5-year overall survival between the patients with ERK5 expression at high level and at low level. CONCLUSION: ERK5 protein is highly expressed in CRC with distant metastasis. This may be a promotive factor in the process of distant metastasis. 相似文献
30.