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1.
[目的]探寻浚单29不同肥力水平地区的适宜种植密度。[方法]研究在高产田与一般田2种肥力水平下浚单29种植密度与产量及其相关产量性状的关系。[结果]2种肥力水平下通过种植密度变化影响穗部性状来影响产量,相同密度,一般田肥力水平下,密度对穗部性状影响大于高产田对穗部性状影响。[结论]在一般田肥力水平下,浚单29最适宜密度为6.75万株/hm2,高产田肥力水平下,浚单29最适宜密度为7.50万株/hm2。  相似文献   
2.
Th IPK2 is an inositol polyphosphate kinase gene cloned from Thellungiella halophila that participates in diverse cellular processes. Drought is a major limiting factor in wheat(Triticum aestivum L.) production. The present study investigated whether the application of the Th IPK2 gene could increase the drought resistance of transgenic wheat. The codon-optimized Th IPK2 gene was transferred into common wheat through Agrobacterium-mediated transformation driven by either a constitutive maize ubiquitin promoter or a stress-inducible rd29 A promoter from Arabidopsis. Molecular characterization confirmed the presence of the foreign gene in the transformed plants. The transgenic expression of Th IPK2 in wheat led to significantly improve drought tolerance compared to that observed in control plants. Compared to the wild type(WT) plants, the transgenic plants showed higher seed germination rates, better developed root systems, a higher relative water content(RWC) and total soluble sugar content, and less cell membrane damage under drought stress conditions. The expression profiles showed different expression patterns with the use of different promoters. The codon-optimized Th IPK2 gene is a candidate gene to enhance wheat drought stress tolerance by genetic engineering.  相似文献   
3.
小麦抗叶锈病Lr35基因同源序列RGA1侧翼序列的扩增与分析   总被引:1,自引:0,他引:1  
利用小麦抗叶锈病近等基因系材料TcLr35,根据已扩增出的Lr35相关基因组DNA片段RGA1设计3对特异性引物,通过热不对称交错PCR技术获得2个有效扩增片段,将目的片段回收纯化,连接到pGEM-TEasy载体,转化EcoliDH5α感受态细胞中,经EcoRⅠ酶切,验证插入片段,选择合适菌液测序。获得了2条侧翼序列,长度分别为511bp和614bp,与RGA1重叠区分别为293bp和509bp,分别向3'端和5'端延长了208bp和100bp,拼接后序列为915bp。经BLASTn同源性比较与小麦抗叶锈病基因Lr21同源性为93%(score值为674,E值为0.0),与含有Lr10基因的450Kb大片段重叠群同源性为90%(score值为260,E值为7e-66),该研究为克隆Lr35目的基因奠定了基础。  相似文献   
4.
AIM: To investigate the role of microRNA-29b (miR-29b)-mediated TGF-β/Smad signaling pathway in the activation of hepatic stellate cells (HSC) and its effect on the progression of hepatic fibrosis in rats.METHODS: Hepatic liver fibrosis rat model was established, and its HSC were isolated. Normal rat HSC were also obtained and identified in vitro. RT-qPCR and Western blot were used to detect the alterations of miR-29b, TGF-β/Smad signaling pathway-related proteins and liver fibrosis marker proteins in the acquired cells. Finally, the direct targeting binding of miR-29b to TGF-β1 was identified by dual-luciferase reporter assay system.RESULTS: With the activation of HSC, the expression of miR-29b gradually decreased (P<0.01), while the expression of collagen type I and α-smooth muscle actin gradually increased (P<0.01). At the same time, the expression of Smad2/3/4 was significantly increased, and the expression of Smad7 was significantly decreased (P<0.01). Dual-luciferase reporter assay showed that miR-29b bound directly to "UCUCUCCGU" in the 3'UTR of TGF-β1, indicating that TGF-β1 was a downstream target gene of miR-29b.CONCLUSION: miR-29b may be involved in the inhibition of HSC activation and migration, thereby inhibiting the process of liver fibrosis. The biological function of miR-29b may be through the direct targeting of TGF-β1, thus regulating and inhibiting the TGF-β/Smad signaling pathway.  相似文献   
5.
将吸血诱导的亚洲璃眼蜱唾液腺差异表达基因GP29的开放性阅读框插入pGEX-4T-1,转化BL21,表达出一相对质量为53ku的蛋白,其大小与预计结果一致。蛋白质的肽质量图谱和“1381.7511”肽段序列两方面的结果证明,SDS-PAGE胶板上相对质量为53ku的蛋白就是由目的基因表达的GST融合蛋白。该蛋白与Swiss PROT库中的任何蛋白均有较大差别,可能是一个新功能分子。  相似文献   
6.
Amplified fragment length polymorphism (AFLP) analysis was carried out in Thatcher, near isogenic lines (NILs) carrying different genes conferring resistance against wheat leaf rust, and TcLr45 x Thatcher F2 progenies were used to develop markers for Lr45 gene. Sixty AFLP primer combinations were screened and most of them provided clear amplification products, 31 primer combinations displayed polymorphism of TcLr45 in 23 NILs. Two AFLP markers closely linked to the gene Lr45 were acquired: P-AGG/M-GAG261 bp, which was found closely linked to the Lr45 locus at a distance of 0.6 cM on one side, and P-ACA/M-GGT105 bp, which was found at a distance of 1.3 cM on the other side. The specific bands were cloned and subsequently sequenced. The 261-bp fragment produced by P-AGG/M-GAG showed 86% similarity with the sequence of Vulgare Hart I gene; the 105-bp fragment produced by P-ACA/M-GGT showed 96% similarity with the phosphatidylserine decarboxylase gene of the Triticum monococcum. Both included an open reading frame (ORF).  相似文献   
7.
将吸血诱导的亚洲璃眼蜱唾液腺差异表达基因GP29的开放性阅读框插入pGEX-4T-1,转化BL21,表达出一相对质量为53 ku的蛋白,其大小与预计结果一致。蛋白质的肽质量图谱和“1381.7511”肽段序列两方面的结果证明,SDS-PAGE胶板上相对质量为53 ku的蛋白就是由目的基因表达的GST融合蛋白。该蛋白与SwissPROT库中的任何蛋白均有较大差别,可能是一个新功能分子。  相似文献   
8.
高淀粉玉米杂交种巴单29的选育   总被引:1,自引:0,他引:1  
高产、专用玉米品种巴单29(巴玉06-173)组合为巴系0431×巴引03-11。经院内品比、内蒙古自治区区域试验、生产试验和品质分析结果,该品种的主要特点是高产、专用、抗病、适应性强、生育期适中、制种产量高。2011年5月通过内蒙古自治区农作物品种审定委员会审定,审定编号:蒙审玉2011004。  相似文献   
9.
Fire blight is the most devastating bacterial disease of rosaceous plants. Forecasting fire blight infections is important to allow for countermeasures that reduce economic damage in pome fruit production. Current computerized forecasting models are solely based on physical factors such as temperature and moisture, but not on the actual presence of the pathogen Erwinia amylovora. Although the inoculum concentration is considered to be crucial for infection and disease outbreak, most current approaches used for identification of fire blight inoculum including morphological, biochemical, serological, and DNA‐based methods are nonquantitative. Based on a real‐time PCR approach previously published, an improved protocol to be used directly on whole bacteria in the field is described. The method allows for early detection and quantification of the pathogen prior to the occurrence of first symptoms. There is a clear correlation between bacterial abundance and subsequent disease development. However, in some cases, no disease symptoms could be observed despite a pathogen load of up to 3·4 × 106 cells per blossom. Integration of the amount of pathogen detected into refined prediction algorithms may allow for the improvement of applied forecasting models, finally permitting a better abatement of fire blight.  相似文献   
10.
文章介绍了玉米新品种新单29的特征特性并分析了密度对其产量的影响。不同密度对新单29产量的影响较大,达极显著水平;新单29在3500株/667m2密度下,产量最高。密度对新单29的农艺性状影响较小。  相似文献   
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