甜叶菊组培快繁与工厂化育苗技术

以甜叶菊优良品种的茎段为外植体,在MS基本培养基中添加不同浓度的6-BA和NAA,采用侧芽诱导法快速繁殖,研究了甜叶菊的组培快繁与工厂化育苗技术。结果表明,最佳启动培养基为MS+6BA1.5mg/L+NAA0.2mg/L,最佳增殖培养基为MS+6BA0.6mg/L+NAA0.2mg/L,增殖系数4-6,增殖周期15-20 d。最佳生根培养基为1/4MS+NAA0.2mg/L,生根率为100%,且根系发达。经过炼苗移栽,瓶苗移栽成活率在90%以上。     

中药材铁皮石斛组培苗不同培养基的筛选与优化

铁皮石斛组培苗在生长各个阶段对营养物质的需求不一样,培养条件不同组培苗生长结果也不一样。本研究以铁皮石斛种子为材料,通过无菌播种进行原球茎诱导、增殖、分化、生根试验,对各阶段培养基进行比较,以期筛选出最佳培养基条件,为将来铁皮石斛走向工厂化、标准化生产提供思考和借鉴。结果表明,种子萌发以及原球茎诱导的最佳培养基配方是1/2 MS培养基,35 d后萌发率达93.1%。原球茎增殖最佳培养基配方组合是MS+6-BA(1.5 mg/L)+NAA(0.5 mg/L),增殖系数达14.8。原球茎分化成苗的最佳培养基配方组合是MS+6-BA(0.5 mg/L)+NAA(0.2 mg/L),分化率达92.1%,且长势良好。组培苗生根的最佳培养基配方组合是1/2 MS+NAA(1.5 mg/L),生根率达97.7%,根系健壮发达。     

辣木组培苗移栽驯化

对印度改良辣木Moringa oleifera PKM2组培生根苗的培养时间及炼苗时间、移栽驯化时间、移栽基质等因素进行研究。结果表明,组培苗移栽前生根培养15 d、炼苗4 d成活率最高,达90.67%;移栽驯化最佳时间为10月份;移栽驯化基质以水藓泥炭+珍珠岩(4∶1)最为适宜。     

桑芽的组织快繁技术研究

不同物候期的茎段诱芽率不同,以夏季湖桑32的桑芽作为起始外植体。分别以MS和1/2MS培养基添加不同浓度的IBA、6-BA、2,4-D进行桑芽分化和生根诱导,以探究最适桑芽增殖、生根的激素浓度组合以及活性炭对桑组培苗的褐化抑制作用。实验结果表明:最佳丛芽诱导培养基组合为6-BA 1.7 mg·L~(-1)+2,4-D 0.03mg·L~(-1)+IBA 0.05 mg·L~(-1),最佳诱导生根的IBA浓度为0.05 mg·L~(-1),活性炭添加的最佳浓度为1.5~2.0 mg·L~(-1),能有效控制褐化负面影响。炼苗过程中,长势良好的桑苗先进行水培炼苗5~7 d后再移栽到土中,能提高组培苗的成活率。     

白木香组培苗育苗管理技术

文章主要介绍了白木香组培苗育苗管理技术,主要包括育苗苗圃的选择及搭建、苗床的准备、育苗基质的选择、白木香组培苗炼苗技术、苗期的水肥管理及苗期病虫害管理技术,为白木香组培苗育苗技术提供了参考。     

‘易丰’女贞组培快繁技术体系的建立

以‘易丰’女贞(Ligustrum lucidum‘Yi Feng’)当年新发半木质化带腋芽茎段为外植体,以芽繁芽的方式,建立了较为完善的可用于大规模工厂化生产的组培快繁技术体系。研究表明,最佳诱芽(启动)培养基为WPM+0.3 mg/L Kinetin(KT)+0.1 mg/L 6-Benzylaminopurine(6-BA)+0.05 mg/L 1-Naphthylacetic acid(NAA),腋芽萌发率达到95.6%;最佳的增殖培养基为WPM+0.5 mg/L KT+1.0 mg/L 6-BA+0.05 mg/L NAA,平均增殖系数达到5.63;最佳的生根培养基为1/2WPM+1.5 mg/L 3-Indolebutyric acid(IBA)+0.1 mg/L NAA,生根周期约为20 d,生根率约为95.4%,炼苗移栽后成活率达到95%以上。建立的组培技术体系能够满足产业化生产的需要,得到的组培苗后代能够稳定地遗传亲本的优良变异性状。     

‘易丰’女贞组培快繁技术体系的建立北大核心CSCD

以‘易丰’女贞(Ligustrum lucidum‘Yi Feng’)当年新发半木质化带腋芽茎段为外植体,以芽繁芽的方式,建立了较为完善的可用于大规模工厂化生产的组培快繁技术体系。研究表明,最佳诱芽(启动)培养基为WPM+0.3 mg/L Kinetin(KT)+0.1 mg/L 6-Benzylaminopurine(6-BA)+0.05 mg/L 1-Naphthylacetic acid(NAA),腋芽萌发率达到95.6%;最佳的增殖培养基为WPM+0.5 mg/L KT+1.0 mg/L 6-BA+0.05 mg/L NAA,平均增殖系数达到5.63;最佳的生根培养基为1/2WPM+1.5 mg/L 3-Indolebutyric acid(IBA)+0.1 mg/L NAA,生根周期约为20 d,生根率约为95.4%,炼苗移栽后成活率达到95%以上。建立的组培技术体系能够满足产业化生产的需要,得到的组培苗后代能够稳定地遗传亲本的优良变异性状。     

黄山药丛生芽诱导与植株快速繁殖

采用黄山药的带芽茎段为外植体,试验了不同激素处理对芽诱导的影响,通过继代培养诱导丛生芽使大量增殖,经诱导生根和炼苗移栽而完成植株的快速繁殖再生。结果表明,MS 6-BA2.0mg/L NAA0.5-1.0mg/L为芽诱导的最适培养基,MS 6-BA1.0mg/L NAA0.5-1.0mg/L为继代增殖的最佳培养基,月增殖系数约为3倍,1/2MS 1BA0.5mg/L培养基诱导生根相对较好,诱导率为50%,组培苗经炼苗后,移栽成活率可达80%。     

金桂快速繁殖炼苗技术的研究

通过不同生根培养基、炼苗预处理、移栽基质以及叶面施肥等对金桂品种微繁苗炼苗的影响开展试验研究,为目标品种的壮苗快繁提供炼苗的技术支撑。通过对金桂快速繁殖关键技术研究,结果表明,金桂微繁苗生根率和生根数的最佳处理组合为A_3B_2C_3,即B_5基本培养基+2 mg·L^-1NAA+0. 10 mg·L^-16-BA,其生根率、平均生根数分别为:91. 11%、3. 83条/株。炼苗的最佳处理组合为A_3B_2C_3,即以苗圃土∶珍珠岩∶腐殖土=2∶3∶7为炼苗基质,金桂微繁苗炼苗的成活率和苗木增长率分别达到82. 2%、42. 2%。     

紫叶狼尾草的组织培养与快速繁殖

以紫叶狼尾草（Pennisetum setaceum‘Rubrum’）的茎尖或带腋芽的节间为外植体材料,进行了组培快繁技术的实验研究,建立了离体快繁技术体系。结果表明,以MS+6-BA 1.0 mg·L^-1+IBA 0.5 mg·L^-1为较适宜的外植体诱导丛生芽的培养基;以MS+6-BA 1.5 mg·L^-1+NAA 0.1 mg·L^-1+IBA 0.5 mg·L^-1为最佳继代增殖培养基,增殖系数达6.5;以1/2MS+NAA 0.5 mg·L^-1+IBA 0.5 mg·L^-1为最佳生根培养基,生根率100%;将生根组培苗移栽炼苗,30 d后成活率达98%以上。     

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.