花生幼叶为外植体的植株再生系统的建立

本文报道利用花生成熟胚幼叶为外植体获得高频植株再生的方法,为花生转基因提供有效的受体系统。通过诱导培养基TDZ、BA、NAA的浓度以及种子萌发时间、继代培养基种类五个因素不同水平的正交试验,筛选出了分化高频发生的最佳组合为：MS培养基中应含有TDZ 1.0 μmol/L、BA 0.4 μmol/L、NAA 5.0 μmol/L,种子萌发4 d,继代培养基为MS0。本研究表明,五因素中诱导培养基TDZ浓度为诱导花生幼叶分化的主要影响因素,其次为继代培养基、种子萌发时间,而诱导培养基中BA和NAA的浓度作用较小。试管苗生根后移栽田间,可正常开花结果。     

不同激素对花生离体分化的影响

对TDZ和2,4-D等激素在花生成熟胚外植体分化中的影响进行了研究.结果表明,花生成熟胚3～5 d龄实生苗的幼叶和胚轴在低浓度TDZ的诱导下,可分化产生高频不定芽和少量体细胞胚,转到无激素MS培养基或MS BA 0.5 mg/L NAA 0.4 mg/L的培养基后形成丛生苗.丛生苗分离后转入含1/2 MS(大量元素) IBA 0.4 mg/L的培养基中诱导生根,可形成完整的再生植株.幼叶分化率高于胚轴,但胚轴分化成苗速度快.无菌水浸泡16～24 h的胚轴在5～ 30 mg/L 2,4-D的诱导下,分化产生低频不定芽;而胚叶则产生高频体细胞胚,但畸形较严重.     

南欧丹参的组织培养与快速繁殖(简报)

以南欧丹参种子萌发的无菌苗茎段为材料,在MS＋6IBA1．5mg／L＋NAA0．5mg／L＋GA30．05mg/L培养基上进行不定芽诱导与增殖培养,30d继代一次,繁殖系数为4～6;壮苗与生根培养基为1／2MS＋NAA1．0mg/L＋1BA0．2mg／L。本试验建立了南欧丹参的种苗快速繁殖技术规程。     

贯叶金丝桃组织培养的研究

分别以甘肃天水贯叶金丝桃的幼根、幼茎、幼叶为外植体．在1／2MS培养基上附加各类激素,进行贯叶金丝桃的组培实验。研究发现各外植体的增殖速率由高到低分别为幼茎、幼根、幼叶,且得到贯叶金丝桃组培各阶段的最佳培养基成分。诱导愈伤组织的培养基为1／2MS 1．3～1．6mg／L BA 0．2mg／L NAA;培养基1／2MS 1．3～1．6mg／L BA 0．15mg／L NAA有利于不定芽的形成;诱导不定根的培养基为l／2MS IBA0．5～O．8mg／L 蔗糖2．0％。向1／2MS培养基中添加不同的生长素(IAA,IBA,NAA,2．4-D)．在不同浓度梯度的培养基上进行诱导贯叶金丝桃的愈伤组织及不定根的试验,结果表明：生长素IAA,IBA既可诱导愈伤组织,又可以诱导不定根的产生。生长素NAA,2,4-D可诱导产生愈伤组织,但对不定根的诱导作用较差。     

肯氏相思的组织培养(简报)

1．植物名称肯氏相思（Acaciacunninghamia）2．材料类别茎尖、嫩茎段和叶片3．培养条件基本培养基为MS。（1）诱导愈伤组织培养基为：MS＋6－BA1．0＋NAA0．2,（2）诱导分化培养基为：MS＋6－BA0．5＋NAA0.2,（3）诱导生极培养基为：3／4MS＋NAA0．2,以上激素浓度均为mg／L     

叶子花的组织培养与微繁技术研究

叶子花茎尖、茎段接种在MS附加不同浓度组合的6-BA、IAA、IBA、NAA培养基上可诱导茎尖及腋芽的生长而获得无性系芽,无性系芽茎尖和茎段在MS附加6-BA0．5mg／L,NAA0．05mg／L进行继代培养,一般不形成丛生芽,以茎尖生长和腋芽萌生增殖,增殖系数为2．73;高度大于3cm的增殖芽在1／2 MS附加IAA lmg／L、IBA lmg／L、NAA0．2mg／L培养基上生根率为80．5％,生根苗用“二步法”移栽成活率在97％以上。无性系芽的幼叶、茎段在MS附加6-BA和NAA、2,4-D培养基上能高频产生愈伤组织,但愈伤组织在所试验的所有培养基上均无不定芽或胚状体的分化。     

中国野生葡萄组织培养研究

对中国野生山葡萄左山—1、左山—2、燕山葡萄燕山—1和秋葡萄平利—7的叶片、叶柄、茎段及单芽茎段进行了离体培养研究。诱导左山—1叶片分化出不定芽的培养基为MS BA 5．0mg／L NAA0．1mg／L,诱导率2．5％;诱导平利—7叶柄分化出不定芽的培养基为MS BA7．0mg／L NAA0．1mg／L,诱导率1．95％;诱导左山—1、燕山—1和平利—7茎段分化出不定芽的培养基与叶柄相同,但诱导率相对较高,分别为8．25％、4．88％和6．49％;应用这一培养基对平利—7、左山—2的单芽茎段进行培养,丛状不定芽的诱导率均为100％。不定芽继代培养基为MS BA0．5mg／L IBA0．2mg／L;生根培养基为1／2MS IBA0．1—0.2mg／L。     

丽格海棠的离体快繁

取丽格海棠幼叶为外植体,在诱导培养基MS＋BA 0．5mg/L NAA 1.0mm/L上培养20d左右,开始分化花芽,培养40d丛生芽长满整个外植体,丛生芽的增殖培养以MS＋BA 0．5mg/L为佳,芽长得大且粗壮,粗壮芽转入无激素的1／2MS生根培养基,生根率达100％。     

皇冠草叶片外植体的体胚发生和植株再生

PlantletReperationandSomaticEmbryogenesisfromYoungLeavesofEchinodorusosirisXINGDeng－Hui(Departmentofbiology,CapitalNormaluniversity,Beijing100037）1植物名称皇冠草（Echinoborusosiris）。2材料类别幼叶（长2～3cm）。3培养条件体胚诱导培养基：（1）MS＋ZT1mg／L（单位下同）＋6－BA1;（2）MS十ZT1＋6－BA1＋NAA0．5;（3）MS＋ZT1＋6－BA1＋NAA1。体胚萌发培养基：MS＋IAA1。以上培养基均含蔗糖30g／L,琼脂8g／L,PH5．8。光照度800lx,每天光照12h,于25℃恒温下培养。毛生长与分化情况叶片经常规…     

翅果油树脱毒试管苗的组织培养技术研究

对翅果油树的无菌苗培养、愈伤组织诱导、继代愈伤组织诱导和生根诱导、褐化现象及预防等进行了研究。结果表明：种子无菌培养的最佳培养基为1／2MS;继代愈伤组织诱导的最佳培养基为N2(MS BA0．5 NAA0．02)、N4(MS BA0．5 NAA0.04);植物激素类型及浓度配比是生根诱导的关键,NAA、GA、IBA为必需激素类型;用多种途径避免和预防了实验过程中的褐化现象,降低了褐化率;建立了翅果油树组织培养高效再生植株的实验体系。     

Recent advances in the study of Kaposi's sarcoma-associated herpesvirus replication and pathogenesis

It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.     

The structure, reproduction and taxonomy of Vidalia and Osmundaria (Rhodophyta, Rhodomelaceae)

Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.     

New or rare chromosome counts in Artemisia L. (Asteraceae, Anthemideae) and related genera from Kazakhstan

Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.     

肝癌中HBV和HCV基因和抗原的分布及意义

采用原位分子杂交方法检测HCV RNA及HBV X基因;采用免疫组织化学方法研究HCV核心抗原,非结构区C33c抗原及HBxAg在肝细胞肝癌中的定位及分布.结果表明(1)HCV RNA、HBV X基因在肝细胞肝癌组织检出率分别为40%(55/136)和82%(112/136).HCV RNA定位于癌细胞的胞浆内,阳性细胞呈散在、灶状及弥漫分布三种形式;HBV X基因在肝癌细胞中的分布呈胞浆型、核型及核浆型,阳性细胞也呈上述三种分布形式;(2)HCV C33c抗原、核心抗原在肝细胞肝癌中的阳性率为81%(133/164)及86%(141/164).C33c抗原定位于癌细胞及肝细胞的胞浆内;核心抗原既定位于癌细胞核中,又可定位于胞浆中.C33c抗原阳性细胞以灶状分布为主;而核心抗原阳性细     

Selection with two alleles and complete dominance

For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment.