矮大黄化学成分研究

目的 对矮大黄根及根茎的化学成分进行研究。方法 采用常压、减压硅胶柱层析、ODS反相硅胶柱层析、Sephadex L H- 2 0凝胶柱层析进行分离 ,通过理化和波谱分析方法鉴定化合物结构。结果 从其石油醚、氯仿部分及正丁醇部分分离得到 14个化合物 ,鉴定了其中 9个化合物 ,分别为 :大黄酚 (chrysophanol, )、大黄素甲醚(physcion, )、大黄素 (em odin, )、正二十六烷酸 (n- hexacosnic acid, )、谷甾醇 (sitosterol, )、谷甾醇葡萄糖苷 (sitosterol- 3- O- glucoside, )、葡萄糖 (glucose, )、大黄素 -龙胆二糖苷 (em odin- gentiobioside, )和大黄酚 - 8O- β- D-吡喃葡萄糖苷 (chrysophanol- 8- O- β- D- glucopyranoside, )。结论 以上化合物均为首次从矮大黄中分离得到 ,其中大黄素 -龙胆二糖苷为首次从大黄属植物中分离得到。

不同浸种方式对矮大黄容器育苗出苗率的影响

宁夏灵武白芨滩国家级自然保护区内生长的矮大黄是一种中药材,具有泻热通肠、凉血解毒、逐瘀通经等药用价值。本文通过设置不同的种子处理方式,比较矮大黄容器育苗种子出苗率。结果表明:当年采收、种粒饱满且无病虫害的矮大黄种子可以不经浸泡直接用于播种,出苗率可达到91.65%,但出苗较慢(7 d开始出苗,15 d出齐苗);18~20℃冷水浸种24 h后用0.3%高锰酸钾溶液浸泡2 h,再用清水淘洗干净阴干后点播,出苗率可达到92.80%,且出苗较快(3 d开始出苗,10 d出齐苗)。在种子处理方式相同的条件下,采收的种子第2年播种出苗率较采收当年播种出苗率低。

Identification of Molecular Markers for the Thinopyrum intermedium Chromosome 2Ai-2 with Resistance to Barley Yellow Dwarf Virus

The wheat_ Thinopyrum intermedium addition lines Z1,Z2 contain a pair of Th. intermedium chromosomes 2Ai_2 carrying the gene with resistance to barley yellow dwarf virus (BYDV). Genomic in situ hybridization (GISH) was used to analyze the chromosome constitution of Z1,Z2 by using genomic DNA probes from Th. intermedium and Pseudoroegneria strigosa . The results showed that the chromosome constitution of either Z1 or Z2 composes of 42 wheat chromosomes and two Th. intermedium chromosomes (2Ai_2). The 2Ai_2 chromosome is St_E intercalary translocation, in which the E genomic chromosome segment translocated into the middle region of the long arm of chromosome belonging to St genome. With the genomic DNA probe of Ps. strigosa , the GISH pattern specific to the 2Ai_2 chromosome may be used as a molecular cytogenetic marker. A detailed RFLP analysis on Z1, Z2 and their parents was carried out by using 12 probes on the wheat group 2 chromosomes. Twenty RFLP markers specific to the 2Ai_2 chromosome were identified. Two RAPD markers of OPR16 -350 and OPH09 -1580 , specific to the 2Ai_2 chromosome, were identified from 280 RAPD primers. These molecular markers could be used to assisted_select translocation lines with small segment of the 2Ai_2 chromosome and provide tools to localize the BYDV resistance.

Transient Expression of BYDV-MP in Nicotiana benthamiana

[Objective]The aim of this study was to identify transient expression of movement protein （MP） gene in Nicotinana benthaminana rapidly and further investigate the function of this exogenous gene. [Method]The movement protein gene of barley yellow dwarf virus （BYDV） was cloned into potato virus X （PVX） viral vector of pGR107,and PVX-recombinant vector was obtained. After electroporation of Agrobacterium tumefaciens,PVX was inoculated into the lower leaves of tobacco by Agrobacterium infiltration assay to observe the infection of virus on tobacco. [Result]After infection for 7 days,upper non-inoculated leaves of tobacco infected by the PVX-recombinant vector showed the virus infection symptoms,while the control group had no viral infection phenomenon. Daily follow-up observations for two groups revealed that tobacco infected by PVX-recombinant vector had severe symptoms of virus infection and curling leaves,or even led to necrosis both in infiltrated and systemic leaves in late period. However,tobacco infected by PVX vector had only slight symptoms of virus infection and could recover from infection. RT-PCR of the infected tobacco indicated that exogenous gene BYDV-MP had a normal transcription and expression in tobacco. [Conclusion]As a determinant factor for viral disease,BYDV-MP promotes the systemic infection rate of PVX and its symptom. In addition,it is feasible to express exogenous MP gene in Nicotiana benthaminan via PVX expression vector.

Investigation of the mechanism of adult-stage resistance to barley yellow dwarf virus associated with awheat-Thinopyrum intermedium translocation

Barley yellow dwarf virus(BYDV)can infect wheat(Triticum aestivum L.),leading to yield loss.Among four BYDV strains(GAV,GPV,PAV,and RMV)identified in China,BYDV-GAV is the prevailing isolate.YW642,a wheat–Thinopyrum intermedium translocation line,is resistant to BYDV isolates at both seedling and adult stages.Zhong 8601 is the wheat recurrent parent of YW642 and is susceptible to BYDV.In this study,we investigated the adult-stage resistance mechanism of YW642,measured BYDV titer and hydrogen peroxide(H_2O_2) in adult-stage leaves of YW642 and Zhong 8601 inoculated with BYDV-GAV,and identified transcriptional differences between YW642 and Zhong 8601 using microarray-based comparative transcriptomics.Enzyme-linked immunosorbent assay and H_2O_2assay showed that both BYDV titer and H_2O_2 content were markedly lower in YW642 than in Zhong 8601 at 21,28,35,and 40 days post-inoculation(dpi).The transcriptomic comparison revealed that many types of genes were significantly up-regulated at 35 dpi in adult-stage leaves of YW642 compared to Zhong 8601.The important up-regulated genes associated with the adult-stage resistance encoded 15 resistance-like proteins,pathogenesis-related proteins(such as defensin and lipid transfer proteins),protein kinase homologs,transcription factors,reactive oxygen species scavenging-related proteins,and jasmonic acid and gibberellic acid biosynthesis enzymes.These results suggest that precise expression regulation of these proteins plays a crucial role in adult-stage resistance of YW642 against BYDV infection.

Effect of Natural Infection with Onion Yellow Dwarf Virus （OYDV） on Yield of Onion and Garlic Crops in Egypt

Present work highlights, first time in Egypt, the impact of OYDV infection on crops production. Plants grown in the field were individually labelled as either apparently healthy or diseased and were marked for harvesting. The percentage of yield loss due to viral infection was determined, on the basis of the average yield parameters of the healthy plant. The natural infection with OYDV in onion and garlic fields resulted in a substantial reduction in pseudo-stem length, number of leaves, plant weight and weight of bulb as well as number and weight of cloves. Results clearly indicate the impact of natural infection with OYDV on the crop yield of infected onion and garlic plants in comparison with the virus-free （uninfected） ones. The largest reduction in the yield of infected plants occurred in Chinese garlic （Seds40） followed by （Baladi） garlic and onion Giza 20. This information suggests that measures have to be taken to prevent natural infection with OYDV into and within onion and garlic fields in order to avoid yield loss.

可克达拉简史

在喝着湘江岷江浦江滦河海河之水 长大的汉子们 抵达这里之前 只有涩嘴的风嚼着黄羊尾巴 在戈壁滩上游荡