滤纸对青蒿丛生芽诱导及遗传转化的影响

研究了滤纸对青蒿丛生芽诱导及遗传转化的影响.结果表明,培养基上加铺一层滤纸能够明显促进青蒿丛生芽的诱导,丛生芽诱导率可达到97%.在高效丛生芽诱导体系的基础上,探讨了滤纸在根癌农杆菌介导的青蒿遗传转化中的应用.优化后的青蒿转化体系,抗性丛生芽诱导率可达到59.7%,其中,12.5%的抗性丛生芽能发育成抗性生根植株,生根植株PCR检测均为阳性.在部分PCR检测阳性植株中检测到了GUS的稳定表达.该优化的转化体系对青蒿素生物合成分子调控的研究具有重要意义.图5表1参26     

Effects of traffic pollution on the genetic structure of Poa annua L. populations

The genetic composition of Poa annua L, populations with a series of traffic pollution was studied by starch electrophoresis. Five enzyme systems were stained. The results showed that: (1) Traffic pollution can dramatically change genotypic frequencies at some loci of P. annua populations. Significant deviations from HardyWeinberg equilibrium were observed on loci Fe - 1 and Me due to the excess of heterozygotes in some populations.(2) The effective number of alleles per locus and the observed and expected heterozygosity were higher in the pollution series than in the clear control site(Botanic Park population), but the increase was not related with the pollution extent. (3) Most genetic variation was found within populations, and only 6.21% was among populations of the polluted series. Slightly higher differentiation( FST = 7.98%) was observed when the control population was included. (4) The calculated gene flow(Nm) is 2.8841 per generation. The mean of genetic identity is 0.9864 and the genetic distance average to 0.0138.     

青蒿毛状根分支生长的动力学模型

近年来，用m质粒转化药用植物诱导毛状根生产有用代谢产物的研究日益增多，转化产生的毛状根不仅生长迅速，分支多，而且遗传性和生理、生化特性稳定，具有较强的次生代谢合成能力，因此可望应用于大规模生产有用的次级代谢产物［‘－’］．青蒿毛状根可产生大量的次生代谢产物     

青蒿试管苗开花及用花器官为外植体诱导丛生芽生产青蒿素

将培养于MS培养基上5wk的青蒿试管苗置于光周期13,光强6000lx,温度为26℃（昼）和22℃（夜）的条件下,成功地诱导其开花,利用不同发育阶段的花蕾和花器官为外植体诱导丛生芽,发现不同浓度（ρ）的6－BA对丛生芽的诱导率和青蒿素的生物合成有重要影响。结果表明：以花蕾为外植体诱导丛生芽的最佳培养基是：MS附加4.0mg L^-1的6－BA和0.05mg L^-1的NAA;但当ρ（6－BA）在0－0.5mg L^-1之间时,有利于青蒿素的合成ρ（6－BA）=0.5-4mg L^-1时抑制青蒿素的生命合成,丛生芽中促进青蒿素合成的最佳ρ（6－BA）为0.5mg L^-1,用HPLC法测定发现用此法得到的丛生芽青蒿素的含量比直接利用叶片诱导的丛生芽青蒿素含量高1倍。     

Occurrence of the non-native annual bluegrass on the Antarctic mainland and its negative effects on native plants

Few non-native species have colonized Antarctica, although increased human activity and accelerated climate change may increase their number, distributional range, and effects on native species on the continent. We searched 13 sites on the maritime Antarctic islands and 12 sites on the Antarctic Peninsula for annual bluegrass (Poa annua), a non-native flowering plant. We also evaluated the possible effects of competition between P. annua and 2 vascular plants native to Antarctica, Antarctic pearlwort (Colobanthus quitensis) and Antarctic hairgrass (Deschampsia antarctica). We grew the native species in experimental plots with and without annual bluegrass under conditions that mimicked the Antarctic environment. After 5 months, we measured photosynthetic performance on the basis of chlorophyll fluorescence and determined total biomass of both native species. We found individual specimens of annual bluegrass at 3 different sites on the Antarctic Peninsula during the 2007-2008 and 2009-2010 austral summers. The presence of bluegrass was associated with a statistically significant reduction in biomass of pearlwort and hairgrass, whereas the decrease in biomass of bluegrass was not statistically significant. Similarly, the presence of bluegrass significantly reduced the photosynthetic performance of the 2 native species. Sites where bluegrass occurred were close to major maritime routes of scientific expeditions and of tourist cruises to Antarctica. We believe that if current levels of human activity and regional warming persist, more non-native plant species are likely to colonize the Antarctic and may affect native species.     

流化床生物反应器培养青蒿毛状根生产青蒿素

利用自制的流化床生物反应器进行青蒿毛状根多层培养生产青蒿素．对毛状根在生物反应器生长过程的形态特征进行观察,并在合适的工艺条件下,经２０ｄ分批培养获得生物量干重２１．３ｇ／Ｌ,青蒿素产量３４９．８ｍｇ／Ｌ,并对培养过程中底物消耗的动力学进行了研究．     

发根农杆菌转化青蒿影响因素的研究

对叶盘法转化过程中各种影响因素进行研究．结果表明：发根农杆菌种类、基本培养基和青蒿株系对转化率有明显影响,而培养基ｐＨ在５．２～５．８对转化率没有明显影响;发根农杆菌ＡＴＣＣ１５８３４的转化率最高;基本培养基中ＭＳ效果最好;青蒿株系０２５对发根农杆菌最敏感;处于对数生长期的发根农杆菌（Ｄ６６０ｎｍ＝０．７５）稀释５倍后用来转化效果最好;幼嫩的叶片的转化率比成熟叶片高;向共培养培养基中加入乙酰丁香酮等酚类物质对转化没有促进作用．在最适的转化条件下,发根农杆菌ＡＴＣＣ１５８３４对青蒿株系０２５的转化率可达到１００％．ＰＣＲ检测证明,青蒿发根基因组中含有发根农杆菌Ｒｉ质粒ＴＤＮＡ上的ｒｏｌＣ片段．     

No difference in activity of Sod-1 genotypes of Poa annua to short-term treatment of ambient gaseous organic pollution

Our previous studies indicated that genotypes at locus Sod-1 of Poa annua changed clinally along a gradient of gaseous organic pollution. In the present study, we aimed to know whether there were differential responses of activities of different superoxide dismutase （SOD） genotypes to short-term treatment of ambient gaseous organic pollution. Significant bias from Hardy-Weinberg equibrium was observed on locus Sod-1, and no genotype Sod- l-BB was found. Significantly increased activities were observed in most treatments for genotype Sod-1-AA and in one treatment for genotype Sod-1-AB. However, no significant difference in SOD activities was found between the two genotypes. It was interpreted that fitness difference between the two genotypes was small and treatment duration was too short or extent of ambient organic pollution was too low to lead to differential responses. Other environmental factor effects on activities of superoxide dismutases can also explain the results.     

大气硫氧化物污染对早熟禾种群遗传结构的影响

大气硫氧化物是我国影响最为严重的污染物之一,本文采用同工酶分析技术研究了大气硫氧化物污染对1年生植物早熟禾种群遗传结构的影响、结果表明,污染地点和清洁地点种群间等位基因频率存在较大差异,但污染种群之间和清洁种群之间等位基因频率比较一致．污染种群的遗传变异明显低于清洁种群,污染种群和清洁种群间的Nai’s遗传距离为0.135～0.150,G_ST为0.202,表明在污染种群和清洁种群之间存在较大的差别．计算的基因流强度较小,为0.988,这与污染地点选择压力较大有关,掩盖了实际种群间的扩散强度．     

雾化生物反应器培养青蒿毛状根生产青蒿素

利用超声雾化生物反应器进行青蒿毛状根多层培养生产青蒿素．对超声雾化生物反应器中营养雾流动状况及毛状根生长过程的形态特征进行观察,并在合适的工艺条件下,经20d分批培养获得生物量10．3g／L,青蒿素产量179．1mg／L．