对氮素反应敏感性不同的水稻叶色基因型鉴定

氮素是水稻生长必需的大量营养元素,提高氮素的吸收利用效率是水稻育种和栽培的重要目标之一。水稻叶色与氮素水平密切相关,叶色值可作为叶片氮含量的诊断指标之一。本试验在大田不施氮素及常规施氮两个处理下,以叶片的SPAD值作为氮素能力评价参数,对146个不同基因型水稻进行了叶色深浅及对氮素敏感性不同的种质资源鉴定。通过测定抽穗前不同生育时期不同基因型水稻叶片的SPAD值,鉴定出对氮素不敏感且叶色较浅基因型7个（9103、临粳8选系、两优培粳、信粳06j1、丰糯、阳光香稻、红米稻）、对氮素不敏感且叶色较深基因型9个（9668、9002-1-1、年香粳、淮稻6号、黑稻、3优32、9910-2、矮香、方欣4号）和对氮素敏感基因型3个（白香粳、牟香粳、日本早稻）。     

毛竹茎秆伸长过程中赤霉素生物合成、降解和信号转导关键基因的鉴定及表达分析

赤霉素(Gibberellin)是一类非常重要的植物激素,在高等植物生命活动的整个周期都起着重要的调控作用。从毛竹Phyllostachys edulis基因组中共鉴定出23个赤霉素途径基因,包括赤霉素生物合成相关的8个GA20ox和1个GA3ox基因、降解相关的8个GA2ox基因、参与赤霉素感知的2个GID1基因以及信号转导的2个GID2基因和2个DELLA基因。拟南芥、水稻和毛竹的系统进化树和保守基序分析显示赤霉素的合成代谢与信号转导在这些物种中是高度保守的。利用外源赤霉素处理毛竹种子和幼苗,发现赤霉素能显著提高种子的萌发率和幼苗的茎秆伸长,并且有着最佳的作用浓度。在GA3处理后,毛竹体内赤霉素生物合成基因GA20ox和GA3ox表达量均下调而降解活性赤霉素的GA2ox基因表达量上调;赤霉素受体GID1和正调控基因GID2的转录水平显著提高而负调控基因DELLA的表达受到抑制。这些基因在竹笋茎秆的不同形态学位置表达差异明显,大部分赤霉素生物合成与降解的相关基因GA20ox、GA3ox和GA2ox以及赤霉素受体GID1和正调控基因GID2都在竹笋的形态学上端大量表达,而赤霉素信号转导的阻遏基因DELLA在笋体形态学底端大量积累而顶端基本不表达。     

超声波和赤霉素对川西獐牙菜种子萌发能力的影响

采用超声波、赤霉素、超声波和赤霉素相结合的方法处理种子,研究3种处理对川西獐牙菜种子萌发能力影响的结果表明：超声波超声20-40min对种子的萌发均有促进作用,其中以超声35min的效果较好,种子发芽提前1-2d;浓度为1000-2000mg·L^-1的赤霉素（GA3）对种子萌发有一定的促进作用,其中以1500mg·L^-1GA3浸种24h的效果较好;超声波和赤霉素共同处理对种子发芽有协同效应,其中以超声35min和赤霉素浓度为1250-1500mg·L^-1浸种22h的效果较为明显。     

臭椿种子萌发最适条件研究

采用不同浓度赤霉素(GA3)处理臭椿种子,在不同温度及不同光照条件下,研究了GA3、温度及光照对臭椿种子萌发的影响。结果表明,40 mg.L-1的GA3质量浓度、30℃温度以及自然光暗交替处理为臭椿种子萌发的最适条件,臭椿属于喜高温型种子。     

赤霉素和脱落酸对黑稻黄化幼苗中胚轴伸长生长的作用研究

研究了不同浓度的GA和ABA对三种黑稻黄化幼苗中胚轴伸长生长的影响。结果表明 :1.2 5 μmol/L的GA和ABA对三种黑稻黄化幼苗中胚轴的伸长生长有显著的促进作用 ,GA效应高于ABA ;三个供试稻种中 ,黑帅对GA和ABA的反应最为显著 ,且GA和ABA对其有叠加效应     

脱落酸和赤霉素对木枣果实成熟衰老和生理特性的影响

用不同浓度的外源激素脱落酸(abscisic acid,ABA)和赤霉素(gibberellic,GA3)分别处理木枣果实,研究外源ABA和GA3对木枣果实成熟衰老的影响。结果表明,枣果组织中,随着ABA处理浓度的增加,丙二醛(malondialdehyde,MDA)含量呈先升高后降低的趋势,而GA3处理则变化趋势相反;脯氨酸(Proline)含量随着ABA浓度的增加呈先缓慢升高后降低的趋势,而随GA3处理浓度增加呈直线下降趋势;维生素C(Vit C)含量随着ABA浓度的增加呈先急剧升高后快速降低的趋势,而GA3处理则呈相反趋势;过氧化氢酶(catalase,CAT)活性随着ABA浓度的增加呈先降低后升高的趋势,GA3处理则保持了较低水平状态。表明ABA与GA3作为信号分子对木枣果实成熟衰老的影响较为明显,其生理作用在多方面表现为相互制约或互为拮抗特征。     

外源赤霉素对心里美萝卜幼苗花青素的影响

花青素是植物体内广泛存在的一类天然色素,具有重要的生理功能。花青素合成途径可受多种因素调控,其中植物生长激素赤霉素（gibberellic acid,GA）对其的调控作用报道较少。本文用不同浓度的赤霉素处理心里美萝卜幼苗,以探讨它对花青素含量的影响。结果表明,外源GA3处理显著增加了萝卜幼苗的下胚轴长度,并提高了下胚轴中α-淀粉酶活性;显著降低下胚轴中花青素的含量。1 μmol/L GA3处理效果较好;处理后第3 d和第5 d,花青素合成的关键酶查尔酮合酶、查尔酮异构酶和花青素还原酶编码基因的表达水平均低于对照组。同时,外源GA3显著诱导过氧化物酶活性的升高。上述结果表明,外源赤霉素可能通过下调花青素合成基因的表达,提高过氧化物酶活性和促进下胚轴伸长生长降低花青素的水平。     

几种外源激素对杜仲剥皮再生的影响

杜仲剥皮后,在暴露表面,分别涂以适当浓度的乙烯利、2,4-D、萘乙酸(NAA)和赤霉素(GA),以及 NAA GA 等植物激素,可看到不同的反应。发现用2,4-D、GA 和 NAA处理的,木栓形成层和维管形成层的发生都早于对照,而用乙烯利处理的,只是木栓形成层的发生提早。只有用 NAA 处理的,木栓形成层和维管形成层的发生都与对照相似。     

外源赤霉素GA3对混合盐碱胁迫下小白菜种子萌发的影响

以小白菜（Brassica campestris ssp．chinensis L．）为材料,通过采用不同浓度的外源赤霉素（GA3）浸种处理,研究了GA3对混合盐碱胁迫下小白菜种子的发芽率（Gr）、发芽势（Gv）、发芽指数（Gi）以及根毛区宽度和胚长的影响。结果表明：混合盐碱胁迫下,小白菜各发芽指标均显著低于对照,GA,处理后,各指标均显著提高,且随外源GA3浓度的增加,各指标均表现出先增后减的趋势,当GA3浓度达80mg／L时,各发芽指标达到峰值,说明80mg／LGA3可使混合盐胁迫下小白菜种子萌发的缓解作用达到最佳。同时外源GA3处理还可不同程度地缓解盐胁迫对小白菜种子a-淀粉酶活性的抑制。     

低温层积与外源GA3对肉苁蓉种子萌发及其内源GA和ABA含量的影响

研究低温层积对肉苁蓉种子胚率、内源赤霉素（GA）和脱落酸（ABA）含量以及外源赤霉素（GA3）对低温层积不同时间种子萌发率影响的结果表明：低温层积可以提高种子的胚率及其GA的含量,降低其ABA含量;层积120～150d的肉苁蓉种子经外源GA3处理后,其萌发率可以达到70%以上;层积120d是外源GA3促进种子萌发的临界点。     

3种杂交杨在不同盐碱地上的生长和生理适应性研究

杂交杨树是松嫩平原盐碱地重要的园林和造林树种,野外长期监测是评价和优选优良品种的关键。本研究在自然条件下（5~12月）,以大庆不同盐碱地上生长的青山杨(Populus pseudo-cathayana×P. deltodides cv. Shan Hai Guan)、小黑14（Populus×xiao hei T. S. Hwang et Liang ‘14’）及中黑防(Populus deltoids×P. cathayana)的4年生扦插苗为研究对象,通过对3种杂交杨生长量、根系活力、根呼吸量和叶绿素含量的对比和分析,探讨其在盐碱地生长的适应性及耐盐能力的差异。结果表明,随盐碱胁迫加强（土壤电导率609.33~910.48 μs·cm^-1,pH值（8.92~8.98）,各杂交杨的生长量受到明显抑制,其中中黑防和小黑14株高均下降达到40%,而青山杨的株高只下降了20%,是前者的一半。随盐碱胁迫加强,根系活力和呼吸作用增强,青山杨、中黑防和小黑14的根系活力分别提高了10.75%、15.90%和33.17%,而根系呼吸青山杨仅上升3.59%,中黑防和小黑14则上升了24%以上。但是盐碱胁迫对于叶绿素含量影响较小,年平均值稍有降低,叶绿素a/b的比值则增大,不同品种间差异较小。综合对3种杂交杨的各项指标的研究,青山杨的耐盐碱能力更强,生长量显著高于目前在盐碱地区较为普遍应用的小黑14和中黑防,比较而言,青山杨是盐碱地区造林与绿化树种的优良杂交杨品种。     

Apolipoprotein E gene polymorphism and serum lipid levels in the Guangxi Hei Yi Zhuang and Han populations

Hei Yi Zhuang is an isolated subgroup of the Zhuang minority in China. Little is known about the distribution of apolipoprotein (apo) E genetic variations and its role in lipid metabolism in this population. The present study was undertaken to compare the effect of apoE gene polymorphism on serum lipid levels between the Guangxi Hei Yi Zhuang and Han populations. A total of 873 subjects of Hei Yi Zhuang and 867 participants of Han Chinese were surveyed by a stratified randomized cluster sampling. Genotyping of apoE was performed using polymerase chain reaction and restriction fragment length polymorphism. The frequencies of 2, 3, and 4 alleles were 15.23%, 79.84%, and 4.93% in Hei Yi Zhuang, and 9.23%, 81.43%, and 9.34% in Han (P < 0.001); respectively. The frequencies of 2/ 2, 2/ 3, 2/ 4, 3/ 3, 3/ 4, and 4/ 4 genotypes were 4.70%, 17.86%, 3.21%, 68.16%, 5.50%, and 0.57% in Hei Yi Zhuang, and 2.54%, 9.23%, 4.15%, 70.70%, 12.23%, and 1.15% in Han (P < 0.001); respectively. Total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), and apoB levels were lower in Hei Yi Zhuang than in Han (P < 0.01-0.001), but high-density lipoprotein cholesterol (HDL-C) levels and the ratio of apoA-I to apoB were higher in Hei Yi Zhuang than in Han (P < 0.001 for each). There were significant differences in TC, HDL-C, LDL-C, and apoB levels among the six genotypes in both ethnic groups (P < 0.01-0.001). Hyperlipidemia was positively correlated with age, body mass index, hypertension, alcohol consumption, and apoE allele in both populations (P < 0.05-0.001). TC, LDL-C, and apoB levels were positively correlated, and HDL-C levels were negatively associated with apoE genotypes in both ethnic groups (P < 0.001 for all). The differences in the lipid profiles between Hei Yi Zhuang and Han Chinese might partly attribute to the differences in apoE genotypic and allelic frequencies.     

Microcultures of lactic acid bacteria: characterization and selection of strains,optimization of nutrients and gallic acid concentration

Eighteen lactic acid bacteria (LAB) strains, isolated from coffee pulp silages were characterized according to both growth and gallic acid (GA) consumption. Prussian blue method was adapted to 96-well microplates to quantify GA in LAB microcultures. Normalized data of growth and GA consumption were used to characterize strains into four phenotypes. A number of 5 LAB strains showed more than 60% of tolerance to GA at 2 g/l; whereas at 10 g/l GA growth inhibition was detected to a different extent depending on each strain, although GA consumption was observed in seven studied strains (>60%). Lactobacillus plantarum L-08 was selected for further studies based on its capacity to degrade GA at 10 g/l (97%). MRS broth and GA concentrations were varied to study the effect on growth of LAB. Cell density and growth rate were optimized by response surface methodology and kinetic analysis. Maximum growth was attained after 7.5 h of cultivation, with a dilution factor of 1–1/2 and a GA concentration between 0.625 and 2.5 g/l. Results indicated that the main factor affecting LAB growth was GA concentration. The main contribution of this study was to propose a novel adaptation of a methodology to characterize and select LAB strains with detoxifying potential of simple phenolics based on GA consumption and tolerance. In addition, the methodology presented in this study integrated the well-known RSM with an experimental design based on successive dilutions.     

Effects of gum arabic on lipase interfacial binding and activity.

We investigated the surface behavior of gum Arabic (GA) as well as its effects on the lipolytic activity of human pancreatic lipase (HPL) and Humicola lanuginosa lipase (HLL), using emulsions of triacylglycerols (TAG) with various chain lengths. The effects of GA on the interfacial binding of HPL were also investigated. In the presence of 4 mM sodium taurodeoxycholate (NaTDC), GA (3% w/v, final concentration) had no effect on the HPL activity measured in the presence of colipase, whatever the type of TAG used. However, in the absence of bile salts or at low bile salt concentrations, GA inhibited the HPL activity when trioctanoin (TC8) and purified soybean oil (PSO) were used as substrates. At 3% (w/v, final concentration), GA strongly desorbed pure HPL from the TC8 interface and the classical anchoring effect of colipase was clearly observed. Both crude and dialyzed GA solutions were found to be highly tensioactive at the air-water as well as the oil-water interface using the drop technique. In conclusion, GA, or a putative contaminant present in GA, was found to be surface active and to have similar effects to those of bile salts on the interfacial binding and activity of HPL.     

Die Wirkung von Gibberellinsäure und Indolylessigsäure auf die Wurzelbildung von Tomatenstecklingen

Summary Root formation of tomato cuttings was always inhibited by GA, never promoted. The number of roots was reduced and the roots appeared later, so that at the end of the experiment (13 days later) a reduced dry weight resulted. The effect depended on the concentration of GA, the lowest effective concentration being 10^-3 mg/l. Root formation decreased up to 1000 mg/l GA. An effect on the shoot was noted at concentrations above 10 mg/l. Counts of root primordias after 3–5 days showed the same diminution of root formation. The growth of existing primordias seemed not to be influenced by GA.Short-time treatments with GA had a smaller effect, but a 3-day absorption-period resulted in the same decrease as a treatment during the whole experiment. When GA was given after the experiment had started, the first 3 days of treatment were again the most effective. This result shows that the induction of root primordias is inhibited or at least retarded.CCC had no effect on root formation nor was it able to alter the inhibition by GA. IAA alone did not promote the rooting process. In combination with GA (concentration range for both 10^-3–1 mg/l) IAA never reduced the inhibition by GA. On the contrary, 1 mg/l IAA+GA was somewhat more inhibitive than GA alone.     

HPLC assay and pharmacokinetics and tissue distribution study of glycyrrhetinic acid liposomes modified with galactosylated lipid

The aim of this study was to evaluate the pharmacokinetics and tissue distribution of the glycyrrhetinic acid (GA) liposome modified with galactosylated lipid (NOH-GA-LP), compared with GA conventional liposome (GA-LP) and GA solution in mice. The pharmacokinetics and biodistribution of liposomal and solution formulation of GA in mice were studied after intravenous administration. Plasma and tissues were treated using liquid-liquid extraction and determined using reversed-phase high-performance liquid chromatography. Results showed that the mean residence times of NOH-GA-LP (2.99-fold) and GA-LP (2.94-fold) were higher than that of the GA solution in plasma. NOH-GA-LP produced a drug concentration in the liver that was markedly higher than that in other tissues and was approximately 2.0- and 4.8-fold of that of GA-LP and GA solution, respectively. In conclusion, the NOH-GA-LP prepared in this study is a promising sustained-release and drug-targeting system for antitumor drugs.     

A comparison of raw starch-digesting glucoamylase production in liquid and solid cultures of Rhizopus strains

Maximum growth for Rhizopus sp. A-11 was obtained at a zinc ion concentration of 0.7 ppm in a liquid medium. Glucoamylase (GA, EC 3.2.1.3) production in Rhizopus sp. A-11 was maximized at 710 U/ml, at the presence of 75 ppm for calcium and 0.7 ppm of zinc ions in liquid medium. Zinc ion is known as an essential biometal for Rhizopus growth; however, growth was inhibited by the zinc ion concentration, not maximized. Although calcium ion was not necessary to Rhizopus growth, GA production using Rhizopus sp. A-11 was markedly stimulated by calcium ion concentration over 75 ppm in the liquid medium. The GA productivity of the present liquid culture was about 4.4 times higher than that of the solid state culture, based on the unit starch amount in the liquid and solid media carbon source. The characteristics of the GA produced by the Rhizopus sp. A-11 liquid culture were interesting; that is, almost all the GA produced was classified as raw starch-digesting GA (GA-I). Secreted protein in the culture liquid after 30 h was nearly GA, and had a limited amount of impure protein. As a result, it was found that using a Rhizopus culture in a specified metal-ion regulated medium was an effective method for producing GA. Thus the present culture method was renamed the "metal-ion-regulated liquid culture method".     

影响辣椒离体再生芽伸长因素研究

以辣椒子叶为外植体,比较不同浓度BA和IAA激素组合对辣椒再生芽诱导的差异,利用筛选出的高效芽诱导培养基为基础,研究了赤霉素、芽诱导时间、培养基有机成分、不同激素组合和品种等因素对辣椒不定芽伸长的影响。结果表明:不同基因型辣椒子叶再生能力不同,BA3.0mg.L-1 IAA0.5mg.L-1的激素配比对不定芽诱导频率最高;不定芽的伸长百分率随着GA3浓度的增加而增加,GA3的适合浓度为1.0～2.0mg.L-1;不定芽诱导时间对不定芽的伸长有一定的影响,诱导21d的不定芽,其伸长频率明显高于诱导14d的不定芽;B5有机成分在辣椒不定芽的伸长中效果优于MS有机成分;激素组合对不定芽伸长有一定的影响,Zeatin GA3激素组合对伸长效果最好,BA IAA GA3伸长效果较好,BA PAA(苯乙酸,phenylaceticacid) GA3伸长效果次之;不同品种辣椒不定芽的伸长能力有一定差异,楚风和苏椒五号再生芽伸长能力最佳。与IAA和NAA相比,IBA对再生芽生根效果较好。     

Correlation of Endogenous Gibberellic Acid with Initiation of Mango Shoot Growth

Stems of mango (Mangifera indica L.) rest in a nongrowing, dormant state for much of the year. Ephemeral flushes of vegetative or reproductive shoot growth are periodically evoked in apical or lateral buds of these resting stems. The initiation of shoot growth is postulated to be primarily regulated by a critical ratio of root-produced cytokinins, which accumulate in buds and by leaf-produced auxin, which decreases in synthesis and transport over time. Exogenously applied gibberellic acid (GA3) delays initiation of bud break but does not determine whether the resulting flush of growth is vegetative or reproductive. We tested the hypothesis that endogenous GA3, which influences release of these resting buds, may decrease in stem tips or leaves with increasing age of mango stems. GA3 and several other GAs in stem tip buds and leaves were identified and quantified in stems of different ages. The major endogenous GAs found in apical buds and leaves of vegetative mango stems were early 13-hydroxylation pathway gibberellins: GA1, epi-GA1, GA3, GA19, GA20, and GA29, as identified by gas chromatography-mass spectrometry (GC-MS). A novel but unidentified GA-like compound was also present. The most abundant GAs in apical stem buds were GA3 and GA19. Contrary to the hypothesis, the concentration of GA3 increased within buds with increasing age of the stems. The concentrations of other GAs in buds were variable. The concentration of GA3 did not change significantly with age in leaves, whereas that of most of the other GAs declined. GA1 levels were greatest in leaves of elongating shoots. These results are consistent with the concept that rapid shoot growth is associated with synthesis of GAs leading to GA1. The role of GA3 in delaying bud break in mango is not known, but it is proposed that it may enhance or maintain the synthesis or activity of endogenous auxin. It, thereby, maintains a high auxin/cytokinin ratio similar to responses to GA3 that maintain apical dominance in other plant species.