黄山药愈伤组织诱导与分化

采用黄山药野生植株作为外植体,试验了不同激素处理对黄山药愈伤组织的诱导、分化影响,结果表明：不同的外植体的诱导率差别较大,叶片的诱导率最高,最高达到85．7％,茎段的诱导率较低,平均诱导率仅10％左右。以叶片作为外植体诱导愈伤组织的最佳培养基配方为MS 2,4-D2．0mg／L 6-BA2．5mg／L;愈伤组织分化生芽的最佳配方为MS BA1．0mg／L NAA0．5mg／L 蔗糖2％ pH6．4;愈伤组织分化生根的最佳配方诱MS BA1．0mg／L NAA0．1mg／L 蔗糖3％ pH6．80。     

盾叶薯蓣组织培养技术的优化

以盾叶薯蓣的根状茎、茎段、叶柄、幼叶为材料,进行愈伤组织诱导、分化及再生植株形成的研究。结果表明：盾叶薯蓣不同外植体均能诱导出愈伤组织,其中茎段愈伤组织的诱导率最高;不同激素配比的培养基对愈伤组织的形成有很大的影响：以LS为基本培养基,2,4-D浓度为4．0mg／L、6-BA浓度为1．0mg／L的激素配比诱导率最高,达62．5％;以改良MS为基本培养基,2,4-D浓度为2．0mg／L、6-BA浓度为0．5mg／L的激素配比诱导率最高,达71．4％。筛选到优化的分化培养基为改良MS附加2．0mg／L的6-BA和0．5mg／L的Vc,且能直接诱导出根,并形成完整植株。     

安菜的组织培养与植株再生

通过对安菜组织培养的培养基种类、激素配比、碳源的研究,得出适于安菜侧芽分化生长的最佳培养基为MS＋6-BA0．5mg／L＋NAA0．2mg／L。诱导愈伤组织以2,4-D浓度在0．2mg／L～0．5mg／L之间最佳。碳源以蔗糖,浓度3％最佳。以IBA0．5mg／L～1．5mg／L浓度诱导生根效果最好。     

费尔干猪毛菜愈伤组织的诱导、分化及植株再生体系的建立

探讨了植物生长调节剂、外植体等因子对费尔干猪毛菜（Salsola fergartica Drob．）愈伤组织诱导、分化与植株再生的影响。结果表明：2，4-D与6-BA组合使用时，在一定浓度范围内均有愈伤组织产生，最佳的诱导培养基为MS＋2，4-D2．0mg／L＋6-BA0．2mg／L，下胚轴为诱导愈伤组织的最佳材料；愈伤组织继代培养较好的培养基为MS＋NAA0．1mg／L＋6-BA1．0mg／L；愈伤组织不定芽分化培养基为MS＋6-BA0．5mg／L＋NAA0．05mg／L；根分化的培养基为1／2MS＋IBA0．2mg／L，且生根率可达72％。以带柄子叶为外植体，诱导丛生芽的最佳分化培养基为MS＋6-BA1．0mg／L，再生频率可达90．74％。     

欧美黑杨离体再生途径及影响因子的研究

先期完成了以腋芽发育为再生方式的研究后,又对不定芽的发育进行了探索。分别以欧天黑杨特选品系的不同部位外植体进行愈伤组织诱导及植株再生研究,易诱导井易分化出新芽的外植体为幼嫩茎段;通过不同激素浓度合理配比,进行适宜的诱导及分化培养基筛选,培养基为MS 6-BA1．2mg／L NAA0．5mg／L,附加6g／L琼脂,诱导的愈伤组织分化出密集的再生芽;糖分在诱导分化过程中作用突出,其合适浓度为10g/L;愈伤组织的形态及培养时问对分化频率影响较大,最佳的形态为致密的绿色,白色及粉红色的愈伤组织较疏松,分化率很低。不同部位外植体、激素含量、蔗糖浓度、愈伤组织形态及培养时间是明显影响欧美黑杨愈伤组织诱导分化的因子。     

黄花蒿组织培养研究

目的：筛选黄花蒿组织培养的配方，以寻求黄花蒿生长的最佳自然条件。方法：在MS基本培养基中添加不同激素，制备不同培养配方，筛选黄花蒿愈伤组织诱导与分化的最适培养基配方。结果与结论：诱导黄花蒿愈伤组织形成的最佳培养基配方为MS＋6-苄氨基嘌呤（6-BA）（2．0mg／L）＋激动素（KT）（2．0mg／L）；诱导黄花蒿愈伤组织分化的最佳培养基配方为MS＋6-BA（1．0mg／L）＋吲哚乙酸（IAA）（1．0mg／L）。叶片诱导愈伤组织出愈时间最慢，出愈率较低，但其愈伤组织为胚性愈伤组织，后期愈伤组织的分化率、出苗率都很高，且不易产生褐变；带腋芽的茎段诱导愈伤组织形成最快，但分化率不及叶片愈伤组织，易褐变，适于快速转入生根培养基中直接用于快繁；花序基本不形成肉眼可见愈伤组织，直接形成幼苗。     

马齿苋多糖提取物对翅果油树愈伤组织诱导的影响

采用传统热浸提工艺,从马齿苋植株中提取多糖.以B1培养基为基础,通过添加0.15 g/L的抗褐变剂Vc及不同浓度的马齿苋多糖,研究了其对翅果油树愈伤组织培养的抗褐变作用.结果显示:(1)马齿苋多糖对愈伤组织培养中的褐变有一定缓解作用.(2)经筛选,得到0.19 g/L为最适的多糖添加物浓度,子叶愈伤组织产生生物量最多,抗褐变效果与Vc的作用相似,愈伤组织生命周期也明显缩短.     

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。     

野牛草幼穗愈伤组织的诱导及植株再生

以野牛草[Buchloe dactyloides(Nutt．)Engelm．]幼穗为外植体,建立了愈伤组织诱导、继代培养和植株再生体系。结果表明,雌穗比雄穗难以脱分化形成愈伤组织;小于8mm雄幼穗在2mg／L2,4-D培养基上的愈伤组织诱导率为80．0％～86．8％;添加10mg／L AgNO3对愈伤组织诱导率影响不明显,但可改善愈伤组织质量。2mg／L 2,4-D结合0．1mg／L 6-BA的培养基有利于愈伤组织的继代培养;继代超过3次、继代间隔超过3周,愈伤组织分化能力明显下降。雄穗愈伤组织在含1．0mg／L 6-BA培养基上,弱光条件下分化出芽的频率较高,达31．8％～35．0％;附加3％麦芽糖既可减轻褐化程度,又利于丛生芽的分化。分化苗在1/2MS 0．3mg／L IBA培养基上的生根率为62．5％。     

箭胡毛杨愈伤组织诱导、保存与再分化

本研究以箭胡毛杨幼叶为外植体,通过对愈伤组织的诱导、保存的再分化的研究,筛选出适宜的培养基和培养条件。外源激素6－BA与IAA的9种配比中,0．5／0．1对箭胡毛杨愈伤组织诱导率可达90％。蔗糖浓度的大小与愈伤组织增长量成正比,与褐变开始时间成反比,当浓度为2％时,继代周期可长达63d。适宜的光照时间可延长愈伤组织保存期并维持良好的组织结构：日光照14h,愈伤组织褐化时间可达到80d;日光照时间少于12h,愈伤组织松散,颜色黄白,褐变开始时间短。经较长时间保存后未褐变愈伤组织的胚状体和丛生苗分化发生时间与分化率不受继代周期影响。当愈伤组织开始褐化后,组织再分化时间延长,分化率大幅度降低。不同继代周期对再生试管苗的生根无影响。     

Entwicklungsgeschichte und Ultrastruktur von Pollenkitt und Exine bei nahe verwandten entomophilen und anemophilen Angiospermensippen derAlismataceae,Liliaceae, Juncaceae,Cyperaceae, Poaceae undAraceae

Some closely related members of the monocotyledonous familiesAlismataceae, Liliaceae, Juncaceae, Cyperaceae, Poaceae andAraceae with variable modes of pollination (insect- and wind-pollination) were studied in relation to the ultrastructure of pollenkitt and exine (amount, consistency and distribution of pollenkitt on the surface of pollen grains). The character syndromes of pollen cementing in entomophilous, anemophilous and intermediate (ambophilous or amphiphilous) monocotyledons are the same in principal as in dicotyledons. Comparing present with former results one can summarize: 1) The pollenkitt is always produced in the same manner by the anther tapetum in all angiosperm sub-classes. 2) The variable stickiness of entomophilous and anemophilous pollen always depends on the particular distribution and consistency of the pollenkitt, but not its amount on the pollen surface. 3) The mostly dry and powdery pollen of anemophilous plants always contains a variable amount of inactive pollenkitt in its exine cavities. 4) A step-by step change of the pollen cementing syndrome can be observed from entomophily towards anemophily. 5) From the omnipresence of pollenkitt in all wind-pollinated angiosperms studied one can conclude that the ancestors of anemophilous angiosperms probably have been zoophilous (i.e. entomophilous) throughout.

     

Identification and Characterization of the First Equine Parainfluenza Virus 5

正Dear Editor,Parainfluenza virus 5 (PIV5), known as canine parainfluenza virus in the veterinary field, is a negative-sense,nonsegmented, single-stranded RNA virus belonging to the Paramyxoviridae family (Chen 2018). The virus was first reported in primary monkey kidney cells in 1954 (Hsiung1972), then it has been frequently discovered in various     

Pathogenic Characterization and Full Length Genome Sequence of a Reassortant Infectious Bursal Disease Virus Newly Isolated in Pakistan

<正>Dear Editor,Infectious bursal disease (IBD) is one of the most important diseases of the poultry. The IBD virus (IBDV), a nonenveloped virus belonging to the Birnaviridae family with a genome consisting of two segments of double-stranded RNA (segments A and B), targets B lymphocytes of bursa of Fabricious leading to immunosuppression. In Pakistan,poultry farming is the second biggest industry and IBD is the second biggest disease threating the poultry sector.However, there is limited genome information of IBDV     

Mink Circovirus Can Infect Minks,Foxes and Raccoon Dogs

正Dear Editor,Mink circovirus (MiCV), which is clustered in the genus Circovirus of the family Circoviridae, was first described in minks from farms in Dalian, China in 2013 (Lian et al.2014). The complete single-stranded circular genome of the virus is 1,753 nucleotides long and contains two major open reading frames (ORFs), designated ORF1 (Rep gene)and ORF2 (Cap gene)(Lian et al. 2014; Ge et al. 2018).Sequence analysis has shown that MiCV is most closely     

CypA Regulates AIP4-Mediated M1 Ubiquitination of Influenza A Virus

Cyclophilin A (CypA) is a peptidyl-prolyl cis/trans isomerase that interacts with the matrix protein (M1) of influenza A virus (IAV) and restricts virus replication by regulating the ubiquitin–proteasome-mediated degradation of M1. However,the mechanism by which CypA regulates M1 ubiquitination remains unknown. In this study, we reported that E3 ubiquitin ligase AIP4 promoted K48-linked ubiquitination of M1 at K102 and K104, and accelerated ubiquitin–proteasome-mediated degradation of M1. The recombinant IAV with mutant M1 (K102 R/K104 R) could not be rescued, suggesting that the ubiquitination of M1 at K102/K104 was essential for IAV replication. Furthermore, CypA inhibited AIP4-mediated M1 ubiquitination by impairing the interaction between AIP4 and M1. More importantly, both the mutations of M1 (K102 R/K104 R) and CypA inhibited the nuclear export of M1, indicating that CypA regulates the cellular localization of M1 via inhibition of AIP4-mediated M1 ubiquitination at K102 and K104, which results in the reduced replication of IAV.Collectively, our findings reveal a novel ubiquitination-based mechanism by which CypA regulates the replication of IAV.