水稻白叶枯病广谱抗性基因Xa21导入两用不育系培矮64S

以克隆的Xa21基因为外源基因,成熟胚愈伤组织为转化受体,应用农杆菌介导法对水稻两用型核不育系培矮64S进行转化,获46株转基因植株。PCR和Southern分析结果表明,Xa21已整合到受体基因组。用稻白叶枯病病原菌(Xanthomonasoryzaepv.oryzae)菲律宾小种6号接种鉴定,结果表明大多数转基因植株获得了抗病性。已整合的Xa21基因能够稳定地遗传,在所检测转基因株系的T1代中,Xa21基因显示3:1的分离。     

人骨保护素(OPG)重组腺病毒的制备及其生物活性研究

采用RT-PCR法得到人OPG的编码区cDNA,克隆至穿梭质粒pShuttle,构建重组有OPG编码区cDNA的腺病毒DNA,经Pac I 酶切线性化,在脂质体介导下转染HEK293细胞,制备重组腺病毒并测定病毒滴度约为5×10⁶～1.5×10⁷ pfu/mL。体外感染小鼠成肌细胞C2C12,Western blot及ELISA检测证实有OPG蛋白的表达,并可在细胞培养上清中持续表达6周。感染OPG重组腺病毒的C2C12细胞生长状态良好、细胞周期无明显变化。将重组腺病毒加入体外培养的小鼠骨髓细胞的培养基中,诱导形成的破骨细胞数量及在象牙片上形成的吸收陷窝的数量显著减少（P<0.01）。      

Allelopathic effects of Ulva lactuca on selected species of harmful bloom-forming microalgae in laboratory cultures

Allelopathic effects of the green macroalgae Ulva lactuca on the growth of three species of red tide microalgae, Heterosigma akashiwo, Alexandrium tamarense, and Skeletonema costatum were tested in laboratory co-cultures precluding the nutrient and light limitation and the effect of high pH. The growth of all three species of microalgae was significantly (p < 0.01) inhibited by fresh U. lactuca. In nutrient replete semicontinuous co-cultures with U. lactuca, H. akashiwo was completely dead in 12 days, and the growth of A. tamarense and S. costatum was reduced by 48 and 46%, respectively by U. lactuca within 12 days. The U. lactuca culture filtrate exhibited a significant (p < 0.05) inhibitory effect on the microalgae in the first 1 or 2 days, but growth resumed in the following days, and S. costatum growth was slightly (p > 0.05) promoted from day 3. The results suggested that the allelopathic compounds are quickly degradable and a long-term inhibition might need the continuous addition of compounds originated from macroalgae. Dried U. lactuca also exhibited inhibitory effects on the microalgae, and the normalized mean growth rates of microalgae decreased with the biomass of dried U. lactuca. The dependent relationships were y = −2.1208x² + 1.0159x + 0.9752 for H. akashiwo, y = 0.7133x² − 3.5813x + 1.1665 for A. tamarense, and y = −0.2114x² − 1.063x + 1.0873 for S. costatum, respectively. The potential feasibility of utilization of dried U. lactuca against red tide microalgae was 2.0 g dry wt L⁻¹. The present study shows that U. lactuca exhibits negative allelopathic effects on harmful bloom-forming microalgae.     

Secretion, purification, and characterization of a recombinant Aspergillus oryzae tannase in Pichia pastoris

Tannase (tannin acyl hydrolase) is an industrially important enzyme produced by a large number of fungi, which hydrolyzes the ester and depside bonds of gallotannins and gallic acid esters. In the present work, a tannase from Aspergillus oryzae has been cloned and expressed in Pichia pastoris. The catalytic activity of the recombinant enzyme was assayed. A secretory form of enzyme was made with the aid of Saccharomyces cerevisiae alpha-factor, and a simple procedure purification protocol yielded tannase in pure form. The productivity of secreted tannase achieved 7000 IU/L by fed-batch culture. Recombinant tannase had a molecular mass of 90 kDa, which consisted of two kinds of subunits linked by a disulfide bond(s). Our study is the first report on the heterologous expression of tannase suggesting that the P. pastoris system represents an attractive means of generating large quantities of tannase for both research and industrial purpose.     

江淮地区巨峰系葡萄经济性状的Fuzzy综合评判

本文根据Fuzzy集理论,运用多级模型综合评判法,对巨峰系13个品种在江淮地区的经济性状表现作了评价。结果表明,江淮地区发展巨峰系葡萄,应以红伊豆三泽系红伊豆、藤稔三个早熟品种为主,还步缩小巨峰等中晚熟品种的比例。     

侧柏毒蛾越冬虫态探讨

记述了侧柏毒蛾在湖南省衡阳地区的越冬虫态 ,并对该虫在我国其他地区的越冬虫态进行了探讨。通过对有关资料的分析 ,认为侧柏毒蛾在我国南北均以胚胎发育完全的幼虫在卵壳内越冬     

滇金丝猴（Rhinopithecusbieti）现状及其保护对策研究

滇金丝猴（Ｒｈｉｎｏｐｉｔｈｅｃｕｓｂｉｅｔｉ）是我国特有的珍稀濒危动物,生活在海拔３８００～４３００ｍ的原始冷杉林中,但有时也会在４３００～４７００ｍ的低矮灌丛、草甸和流石滩上活动达数小时之久,甚至能跨越近千米的无林高海拔地带,因而它们是海拔分布最高的非人灵长类。松萝是它们的主要食物,取食松萝的时间占总取食时间的９１％。猴群活动范围可达近百平方公里。笔者在历时８年的野外考察中,已查明这一物种的全部现存自然种群只有１３个,分布在云南的德钦、兰坪、潍西、丽江和西藏的芒康这五县境内,其现存种群数量为１０００～１５００只;所有现存自然种群几乎均处在相互隔离的状态,群间已不可能进行基因交流,充分表明它们已到达灭绝边缘。然而其栖息地内的商业伐木规模仍在继续扩大,周围的人口压力正在不断增加,各猴群均面临不同程度的偷猎压力。这一现状委实令人担忧。如何拯救这一“国宝”应引起我国保护学家和各级政府有关职能部门的重视     

长白山北坡阔叶红松林和暗针叶林的土壤水分物理性质

对长白山北坡阔叶红松林和暗针叶林的土壤水分物理性质进行了观测和对比分析.结果表明:两种森林类型的土壤容重和各种孔隙度随土壤深度的变化趋势相同,即随着土壤深度的增加,容重和毛管孔隙度逐渐增加,总孔隙度和非毛管孔隙度逐渐降低;两种森林类型土壤物理性质的差异比较明显,阔叶红松林0～100 cm土层的平均土壤容重、总孔隙度、毛管孔隙度和非毛管孔隙度分别为1.41 g·cm^-3、52.31%、46.11%和6.20%,暗针叶林地土壤分别为0.98 g·cm^-3、50.65%、40.32%和10.33%;阔叶红松林和暗针叶林地土壤100 cm土层贮水能力相差较大,分别为619.89和1 033.05 t·hm^-2.两种森林类型的土壤水分特征曲线与一般土壤水分特征曲线相一致.     

艾比湖湿地芦苇根际土壤氨氧化古菌的多样性和群落结构

【目的】旨在揭示耐盐植物芦苇根际与非根际土壤AOA群落结构间的差异,为深入研究盐生植物根际土壤微生物与耐盐性之间的关系提供理论基础。【方法】应用高通量测序技术以氨单加氧酶基因(amoA)为分子标记,对新疆艾比湖湿地荒漠生态系统不同季节(春、夏、秋)芦苇根际与非根际土壤氨氧化古菌(AOA)的多样性和群落结构进行研究。【结果】结果表明,不同季节芦苇根际土壤AOA多样性和丰富度存在差异,相比非根际土壤,夏季和秋季芦苇根际土壤AOA多样性较低丰富度较高,春季多样性较高丰富度较低。芦苇根际土壤中AOA的多样性为春季夏季秋季。AOA群落组成分析表明,土壤样品中AOA群落主要集中在泉古菌门(Crenarchaeota)和奇古菌门(Thaumarchaeota),其中泉古菌门为主要优势菌门。RDA分析表明,含水量(SM)、有机质(SOM)、总氮(TN)和pH是影响芦苇根际土壤AOA群落多样性和丰富度的主要环境因子。【结论】不同季节芦苇根际土壤AOA多样性及丰富度存在差异,相比非根际土壤,芦苇根际土壤AOA更丰富。     

黄萎病菌胁迫下野生茄子托鲁巴姆防卫反应的生理生化分析

以野生茄子托鲁巴姆(Solanum torvum Swartz)和苏崎茄(Solanum melongena L.)为主要材料,通过比较两种茄子在大丽轮枝菌(Verticillium dahliae Kleb)侵染过程中体内的生理生化指标变化,分析托鲁巴姆对黄萎病的抗性响应机制。结果表明:(1)与苏崎茄植株相比,托鲁巴姆植株表现出很强的自我防御和自我修复能力。(2)托鲁巴姆体内存在的活性氧清除系统(如SOD、POD、CAT等酶的活性)高于苏崎茄;在侵染后,托鲁巴姆体内各种酶的活性快速增加,其幅度高于苏崎茄;MDA的变化则恰恰相反。这个结果提示,黄萎病菌胁迫可能激活了托鲁巴姆体内活性氧清除系统,从而加快了某些防御物质(如木质素和抗菌物质绿原酸等)的形成,同时减缓或降低MDA等有害物质在植株体内的积累。(3)黄萎病菌侵染后各生理指标的响应时间表现出差异。托鲁巴姆中POD、PAL的活性和可溶性蛋白含量在侵染后的12h内就迅速作出响应(POD增加、PAL和可溶性蛋白减少);而SOD、PPO、CAT的活性和MDA的含量则在处理后初始阶段(至少12h)进行了一些调整,随后才进入持续性的增加或减少阶段。由此可见,托鲁巴姆对黄萎病病菌侵染的响应具有时序性,其体内POD酶、PAL酶和可溶性蛋白首先参与植物的防卫反应以应对黄萎病的胁迫,其它酶随后参与响应,它们的共同作用形成对黄萎病菌的有效防卫。