抗病毒剂VA诱导烟草对TMV的抗性与Ca2+的关系

以枯斑三生烟为材料,抗病毒剂VA为诱导剂,用细胞化学沉淀法测定了VA对烟草叶片细胞中Ca^2 分布的影响,并探讨了Ca^2 在植物诱导抗病性中的作用。结果发现,枯斑三生烟健叶中的Ca^2 主要分布于细胞间隙和液泡,喷施VA可以增加健叶细胞间隙中的Ca^2 。接种TMV后,细胞间隙中的Ca^2 逐渐向细胞内转移,在接种后48h,Ca^2 主要分布于过敏性坏死细胞和近坏死区细胞,远坏死区细胞间隙缺Ca^2 ;以后由于枯斑停止发展,远坏死区细胞逐渐恢复钙稳态,VA TMV处理比水 TMV处理恢复钙稳态快,在接种后72h就可恢复,而水 TMV处理的远坏死区要在接种后96h才恢复钙稳态。     

解淀粉芽孢杆菌Ba33对烟草的促生及抗TMV作用

从烟田土壤中分离得到解淀粉芽孢杆菌(Bacillus amyloliquefaciens)Ba33菌株。5叶期三生NN烟(Nicotianatabacum var.samsun NN)喷施Ba33发酵液3次后再接种TMV(烟草花叶病毒),与喷清水对照相比,能显著降低枯斑数量,枯斑抑制率为67.8%。于4~6叶期普通烟草(Nicotiana tobacum L.)NC89烟苗接种TMV前后分别用Ba33发酵液、NB培养基或清水连续灌根3次,观察到Ba33发酵液灌根处理的烟苗鲜重、最大叶长和叶宽均高于清水对照处理,叶色浓绿,长势良好;接种TMV10 d后进行实时荧光定量PCR检测,Ba33发酵液灌根处理的植株新叶中RNA含量低于清水对照和NB培养基灌根处理。认为Ba33具有拮抗TMV、促进烟草生长的作用,是具有潜在应用价值的生防菌株。     

嘧肽霉素复配制剂06抗病毒机理初探

针对自主研制的抗病毒农药嘧肽霉素复配制剂06,以普通烟NC89为试材,通过比色法和生物学测定法研究了4种处理(接种TMV,接种TMV前24h喷06,接种TMV后马上喷06,接种TMV后24h喷06)烟株体内病毒浓度的变化。结果表明:嘧肽霉素复配制剂06对病毒的复制和增殖有一定的抑制作用,并且其保护作用好于治疗作用。同时对4种处理(接种TMV,TMV与06混合接种,喷施06不接种,对照)烟株体内防御酶活性的变化进行了研究,结果表明:嘧肽霉素复配制剂06可使烟株CAT、POD、PAL、PPO的活性比对照均有不同程度的提高,酶活高峰集中表现在4~10d。     

苜蓿假盘菌侵染过程中不同抗性苜蓿品种叶片几种酶活性变化

以不同抗性的苜蓿品种为材料,研究苜蓿在感染假盘菌后,不同品种间的苯丙氨酸解氨酶(PAL)、过氧化物酶(POD)、多酚氧化酶(PPO)、过氧化氢酶(CAT)、超氧化物歧化酶(SOD)、β-1,3-葡聚糖酶的活性变化.结果表明,抗、感品种的PAL,POD,SOD酶活性有逐渐上升的趋势,而CAT则呈逐渐下降的趋势,PPO和β-1,3-葡聚糖酶的酶活性与对照相比,也有显著差异.接种12 h时,抗病品种润布勒的PAL和POD活性较感病品种柏拉图的活性增加幅度大;而感病品种柏拉图的CAT活性较抗病品种润布勒的活性减小幅度小.接种24 h时,抗病品种润布勒SOD酶的活性较感病品种柏拉图增加幅度大.初步表明这些酶与其抗病性具有相关性.     

氨基寡糖素与镁锌混配对烟草TMV的防控效果及生理分析

通过三生烟草(Sam Sun N.N)枯斑试验和接种TMV病毒的K326品种烟株体内生理指标分析,研究了氨基寡糖素与中微肥混配对烟草花叶病毒(TMV)的体外钝化、侵染抑制效果和综合防病效果,以及由其引起的烟叶叶绿素、防御酶活性及病程相关蛋白等生理指标变化。结果表明:三生烟草枯斑试验中,氨镁锌混配剂对TMV病毒有明显的体外钝化和侵染治疗效果,病毒抑制率分别比单独施用氨基寡糖素提高20.6和10.1个百分点;K326品种烟株接种TMV病毒施用相应药剂,接种后7、11和30 d时的病情指数均以氨镁锌混配剂处理氨基寡糖素单剂CK;而上述烟株体内叶绿素的含量和SOD、POD和PAL酶活性则以氨镁锌混配剂处理总体最高;氨镁锌混配剂处理诱导病程相关蛋白PR3和PR5相对表达量显著性升高,达到对照的0.79倍和1.51倍。这说明,氨基寡糖素与镁锌混配对抑制TMV侵染和提高烟株抗性的效果比单独施用氨基寡糖素好。     

烟草对烟草花叶病毒耐受性的早期防御反应

为深入研究植物对烟草花叶病毒(TMV)产生耐受性的机制,以烤烟栽培种NC89和其自然变异株系培育的品种豫烟8号(具有TMV耐受性)为材料,人工接种TMV后,检测其生理生化指标变化及抗性基因表达水平,并进行组织切片比较分析。结果显示,豫烟8号接种TMV 24 h叶片中的超氧阴离子含量、过氧化物酶(POD)活性、苯丙氨酸解氨酶(PAL)活性、过氧化氢酶(CAT)活性都明显高于NC89,而丙二醛(MDA)含量低于NC89,N基因表达水平高于NC89。接种TMV 9 d的烟草组织切片显示:相对豫烟8号,NC89叶片表皮细胞破裂,栅栏组织细胞间排列疏松,海绵组织细胞间隙较大。表明豫烟8号对TMV的耐受性体现在早期的快速应答反应。     

苍耳多糖对烟草花叶病毒的抑制作用及对烟草几种防御酶活性的影响

水提醇沉法从苍耳幼苗中获得不同醇沉级分的苍耳多糖,枯斑半叶法在心叶烟上进行抗烟草花叶病毒(TMV)活性检测,发现苍耳多糖对TMV具有一定的抑制作用,在浓度为1.0mg/mL时,乙醇浓度为30%的条件下获得的多糖对TMV的抑制率为48.36%.测定了苍耳多糖处理普通烟后烟草叶片中过氧化物酶( POD) 、多酚氧化酶( PPO) 、苯丙氨酸解氨酶( PAL)的活性变化,发现喷施苍耳多糖后,可提高烟草叶片POD、PPO、PAL酶的活性,因此苍耳幼苗多糖可能通过诱导烟草中防御酶活性形成对TMV的抑制活性.     

植物源抗病毒制剂 VA 对烟草花叶病毒(TMV)体外钝化作用的初步研究

用植物源抗病毒制剂VA与烟草花叶病毒 (TMV)混合 ,经枯斑半叶法接种 ,结果证明 ,VA对TMV有较强的体外钝化作用 ,体外钝化后的枯斑抑制率为 80 .0 % ;用苯酚氯仿法提取TMV的核酸后 ,按一定的比例与VA混合 ,经枯斑半叶法接种测得枯斑抑制率为 43.8%～ 77.9% ;TMV与VA混合后用RNase处理 ,测得侵染率为 78.6 % ,比未用RNase处理的对照降低了 2 1.4% ,由此说明VA具有一定的体外脱衣壳作用 ;又经电镜观察发现VA可使部分TMV粒体发生断裂或粗细不均、略变弯曲等畸变现象。     

多孢木霉HZ-31菌株对藜的生理生化特性的影响

【目的】明确多孢木霉HZ-31菌株对藜植株体内生理生化特性的影响.【方法】利用酶活力测试法测定了HZ-31菌株接种藜植株后体内丙二醛(MDA)含量、过氧化氢酶(CAT)活性、过氧化物酶(POD)活性、多酚氧化酶(PPO)活性、苯丙氨酸解氨酶(PAL)活性、超氧化物歧化酶(SOD)活性、可溶性糖含量和叶绿素含量.【结果】多孢木霉HZ-31菌株接种藜后其体内MDA和可溶性糖含量及CAT、PPO和SOD的活性较对照明显增加,且呈上升趋势,增加量最高分别达到67.91%、69.37%、81.88%、37.68%和8.12%,7 d后除MDA呈下降趋势外,其他指标均呈增加趋势;叶绿素含量第3天后低于对照,呈下降趋势;POD活性呈平稳变化趋势且始终高于对照;而PAL活性呈先上升再下降的趋势.【结论】多孢木霉HZ-31侵染藜后,藜防御酶体系被激活,抗侵染性增强.     

壳寡糖诱导和TMV侵染烟草防御酶活性的变化

为了明确壳寡糖诱导烟草对TMV的抗病作用机理,以普通烟为供试材料,用壳寡糖(Chito-oligosaccharide)喷雾处理烟草叶片后再接种烟草花叶病毒(TMV),系统研究了壳寡糖处理对烟草防御酶活性变化的影响。结果表明,壳寡糖喷雾处理普通烟草24 h后再接种TMV,烟草叶片中过氧化氢酶(CAT)、过氧化物酶(POD)、超氧化物歧化酶(SOD)和多酚氧化酶(PPO)活性较对照都有明显增加,最高活性高峰分别为空白对照的162.3%,118.4%,265.4%,162.3%,其中CAT和SOD峰值提前。壳寡糖处理后,随着酶活性增强,对TMV的系统诱导抗病性得到表达,其二者具有一定的相关性。     

Optomechanically induced transparency

Electromagnetically induced transparency is a quantum interference effect observed in atoms and molecules, in which the optical response of an atomic medium is controlled by an electromagnetic field. We demonstrated a form of induced transparency enabled by radiation-pressure coupling of an optical and a mechanical mode. A control optical beam tuned to a sideband transition of a micro-optomechanical system leads to destructive interference for the excitation of an intracavity probe field, inducing a tunable transparency window for the probe beam. Optomechanically induced transparency may be used for slowing and on-chip storage of light pulses via microfabricated optomechanical arrays.     

药剂诱导苎麻孤雌生殖效果初报

本试验于１９９４～１９９５年在江西农业大学进行，采用不同种类、浓度和配方的化学药剂诱导湘苎系列１～５号等１３个三麻品种弧雌生殖结实。对不同品种的平均诱导效果，以激动素最佳，二甲亚砜（ＤＭＳＯ）＋秋水仙素（Ｃｏｌ）混合液次之。从各个不同品种的反应来看，１％ＤＭＳＯ对资源１１号、１００μｇ／Ｌ激动素对湘苎４号、２％ＤＭＳＯ＋０．１％Ｃｏｌ对湘苎１号和５号、０．２％ＤＭＳＯ＋０．２％Ｃｏｌ对湘苎３号分别具有较好诱导单性结实作用。化学药剂的种类、浓度、配方均影响诱导效果。诱导产生的弧雌生殖体多为二倍体。     

Collagen defect induced by penicillamine

Collagen synthesis, as judged by the accumulation of collagen in a subcutaneous, induced granuloma, was significantly decreased by penicillamine. Penicillamine also caused a marked increase in the amount of soluble collagen in skin and a sharp drop in insoluble material. These findings, which reflect an abnormal pattern of collagen metdbolism, are accompanied by an inhibition of wound-healing and by skin fragility.     

Interferon induced by Plasmodium berghei

An inhibitor of virus is demonstrable in the serums of mice infected with Plasmodium berghei. The titer of the inhibitor, detectable within 10 hours after injection of parasitized blood, increases rapidly until 30 to 40 hours when it levels off or decreases slightly before reaching a plateau. The factor that induces production of the antiviral substance is not present in the plasma of the infected blood, and the inhibitor is not detectable in serums of mice injected with nonparasitized mouse erythrocytes. The inhibitor fulfills the essential require ments of an interferon.     

植物诱导免疫及其应用研究进展

概述了植物诱导免疫的特点、诱导因子、生理生化与分子机理,简要介绍了诱导免疫技术在植物病害防治中的应用,并讨论了植物诱导免疫研究中存在的问题和今后的发展前景,     

Microfluidic adhesion induced by subsurface microstructures

Natural adhesives in the feet of different arthropods and vertebrates show strong adhesion as well as excellent reusability. Whereas the hierarchical structures on the surface are known to have a substantial effect on adhesion, the role of subsurface structures such as the network of microchannels has not been studied. Inspired by these bioadhesives, we generated elastomeric layers with embedded air- or oil-filled microchannels. These adhesives showed remarkable enhancement of adhesion ( approximately 30 times), which results from the crack-arresting properties of the microchannels, together with the surface stresses caused by the capillary force. The importance of the thickness of the adhesive layer, channel diameter, interchannel spacing, and vertical position within the adhesive has been examined for developing an optimal design of this microfluidic adhesive.     

Strontium induced rickets: metabolic basis

Dietary strontium inhibits both the synthesis of 1,25-dihydroxycholecalciferol and intestinal calcium absorption in vitamin D(3)-repleted chicks. 1,25-Dihydroxycholecalciferol restores calcium absorption to normal, while 25-hydroxycholecalciferol is without effect in the strontium-fed chick. It is suggested that strontium induces rickets by blocking the biosynthesis of 1,25-dihydroxycholecalciferol, the metabolically active form of vitamin D in the intestine.     

HSP104 required for induced thermotolerance

A heat shock protein gene, HSP104, was isolated from Saccharomyces cerevisiae and a deletion mutation was introduced into yeast cells. Mutant cells grew at the same rate as wild-type cells and died at the same rate when exposed directly to high temperatures. However, when given a mild pre-heat treatment, the mutant cells did not acquire tolerance to heat, as did wild-type cells. Transformation with the wild-type gene rescued the defect of mutant cells. The results demonstrate that a particular heat shock protein plays a critical role in cell survival at extreme temperatures.