山茱英的组织培养与植株再生

目的：建立山茱萸的组织培养及植株再生体系。方法：分别以山茱萸的叶片、花柄和花托为材料,进行山茱萸不同外植体的离体培养研究,筛选最佳培养基组成。结果：适宜山茱萸叶片愈伤组织诱导的培养基组合为1／2MS,附加BA2．0mg/L、IBA0,5—1．0mg／L;适宜山茱萸花柄、花托愈伤组织诱导的培养基组合为1／2MS,附加BA1．0mg／L、2,4-D0．5mg／L;在1／2MS附加BA2．0mg／L、IBA0．05mg／L的培养基上,可诱导不定芽的产生;1／2MS附加IBA2．0mg／L的培养基有利于山茱萸试管苗生根。讨论：山茱萸的花托是进行组织培养的最适外植体,白色或翠绿色、结构致密的愈伤组织较易分化产生不定芽。     

樱桃砧木Colt离体叶片再生

以樱桃砧木Colt试管苗的叶片为外植体 ,通过先诱导愈伤组织分化不定芽以及叶片直接分化不定芽两种途径诱导再生。结果表明 :在MS附加NAA 1 0mg/L、KT3 0mg/L、ZT0 2 5mg/L培养基中 ,愈伤诱导率可达 1 0 0 % ;诱导的愈伤在MS附加NAA 0 2mg/L、IAA0 5mg/L、6 BA 0 5mg/L、KT 1 0mg/L、GA 0 5mg/L培养基中 ,不定芽分化率为 2 1 3% ;在MS附加 6 BA 6 0mg/L、NAA 1 0mg/L、GA 0 5mg/L中 ,叶片 -叶柄不定芽诱导率可达 48 3%。     

樱桃砧木Colt离体叶片再生

以樱桃砧木Colt试管苗的叶片为外植体,通过先诱导愈伤组织分不定芽以及叶片直接分化不定芽两种途径诱导再生,结果表明,在MS附NAA1．0mg/L、KT3．0mg/L、ZT0．25mg/L培养基中,愈伤诱导率可达100％;诱导的愈伤MS附加NAA0．2mg/L、IAA0．5mg/L、6－BA0．5mg/L、KT1．0mg/L,GA0．5mg/L培养基中,不定芽分化率为21．3％,在MS附加6-BA6．0mg/L、NAA1．0mg/L、GA0．5mg/L中,叶片一叶柄不定芽诱导率可达48．3％。     

大果良种沙棘愈伤组织诱导及植株再生的研究

大果良种沙棘的幼嫩茎尖,茎段外植体接种在MS,1／2MS附加不同浓度配比的IAA,IBA,BA,NAA培养基上可诱导茎尖及腋芽生长,将诱导产生的无性系芽接种在MS或1／2MS附加BA0．3－0．5mg/L,NAA0．05mg/L的培养基上可形成丛生芽,同时在小叶片和嫩茎上诱导产生愈伤组织,继续培养愈伤组织表面形成大量的绿色突起,进一步分化成不定芽,在相同培养基上,不定芽上可直接产生不定芽,从而形成多达数百个的不定芽族,不定芽长至3cm时切下转至1／2MS附加IAA或IBA 0．2mg/L的培养基上可生根而形成完整 的再生植株。     

白刺组织培养技术的研究

试验选用唐古特白刺幼嫩茎段和叶片作为材料,研究白刺不同外植体的离体培养技术。结果表明,白刺带芽嫩茎是诱导丛生芽的良好外植体,而叶片是诱导愈伤组织的良好外植体;白刺的最适增殖、壮芽培养基是：MS BA0.5mg／L NAA1．0mg／L GA32．0mg／L;最适生根培养基是：l／2MS IBA0.5mg／L;愈伤组织诱导培养基是：MS 2,4-D0.5～1．0mg／L。     

地黄组织培养及植株再生的研究

以地黄根茎所获无菌苗为材料,对其愈伤组织诱导、分化和再生植株的获取进行了初步研究。结果表明：取叶片、茎段、叶柄进行愈伤组织诱导,筛选出最适培养基为MS附加2,4-D0．5mg／L、BA1．0mg／L,愈伤组织诱导率可达100％。将叶片接种在分化培养基中,诱导不定芽,其最适分化培养基为MS附加BA 3mg／L、NAA 0．1mg／L,分化率为77．5％。试管苗在改良的MS(大量与微量元素、铁盐和有机物质各1／2)附加NAA 0．05mg／L的培养基上,经过15～20d培养,生根率可达100％。     

香蕉草叶柄离体培养与快速繁殖(简报)

以香蕉草叶柄为外植体进行离体培养及快速繁殖条件研究。结果表明,叶柄外植体在培养基MS＋6-BA 2．0mg／L＋NAA 0．3mg／L＋蔗糖30g／L＋卡拉胶7g／L上诱导形成愈伤组织后,转入分化培养基MS＋KT 1．0mg/L＋NAA0．2mg/L可诱导不定芽分化;不定芽转入增殖培养基MS＋6-BA 1.0mg/L＋NAA 0．5mg／L可旺盛增殖,增殖系数4．5。不定根分化培养基为MS＋IBA 0．2mg／L＋NAA 0．05mg／L,生根苗在水族箱移栽成活率达98％。     

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。     

火炬松(Pinus taeda L.)合子胚愈伤组织的器官发生和植株再生

以火炬松(Pinus taeda L.)的成熟合子胚为外植体在附加NAA和BA的TE培养基上诱导产生了淡黄色、疏松、有光泽的颗粒状愈伤组织。经过愈伤组织的保持和增殖培养及不定芽原基的诱导培养后,进行了不同激素、低温处理和蔗糖浓度对不定芽分化的影响实验。结果表明,在附加0.5 mg·L~(-1)IBA和2 mg·L~(-1)BA的TE培养基上,愈伤组织上的不定芽分化频率最高达62.15%。不定芽分化的最佳低温处理时间是5—6周,最佳蔗糖浓度是25—30 g·L~(-1)。不定芽经伸长培养后取高于1cm的小苗用于生根。在附加IBA、BA和GA_3的TE培养基上不定芽的生很频率最高达46%。     

不同生长调节剂对狗肝菜愈伤组织诱导和离体快繁的影响

目的 :研究不同生长调节剂对狗肝菜愈伤组织诱导和离体快繁的影响。方法 :狗肝菜不同外植体在附加不同生长调节剂的培养基上诱导愈伤组织 ,比较愈伤组织的诱导率 ;用 3因子 5水平的正交实验 ,比较不同生长调节剂对丛生芽诱导的影响 ;在附加不同生长调节剂的培养基上比较芽增殖倍数 ;附加不同浓度NAA的培养基上比较生根效果。结果 :愈伤组织诱导率相对以叶片最高 ,茎段次之 ,最后为叶柄 ;愈伤组织诱导的最佳培养基为MS 6-BA0 .5 NAA1 .5 ;不同激素对茎段芽诱导的影响次序为 6-BA>KT >NAA ,芽诱导的最佳培养基为MS 6-BA2mg/L KT1mg/L NAA0 .5mg/L ;芽继代增殖的最佳激素组合是MS 6-BA2mg/L NAA2mg/L ,增殖倍数达 3.0 0 ,影响芽继代增殖的因素次序为 6-BA >NAANAA0 .5mg/L的生根效果较好。结论 :附加一定的生长调节剂能提高狗肝菜愈伤组织的诱导率和离体快繁的效率。     

Curcuminoids as inhibitors of thioredoxin reductase: A receptor based pharmacophore study with distance mapping of the active site

Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.     

A Unique Protease Cleavage Site Predicted in the Spike Protein of the Novel Pneumonia Coronavirus (2019-nCoV) Potentially Related to Viral Transmissibility

正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases     

Comparative morphology of the carpel in the Liliaceae: Hewardieae, Petrosavieae, and Tricyrteae

The young pistils in the melanthioid tribes, Hewardieae, Petrosavieae and Tricyrteae, are uniformly tricarpellate and syncarpous. They lack raphide idioblasts. All are multiovulate, with bitegmic ovules. The Petrosavieae are marked by the presence of septal glands and incomplete syncarpy. Tepals and stamens adhere to the ovary in the Hewardieae and the Petrosavieae but not in the Tricyrteae. Two vascular bundles occur in the stamens of the Hewartlieae and Tricyrtis latifolia. Ventral bundles in the upper part of the ovary of the Hewardieae are continuous with compound septal bundles and placental bundles in the lower part. Putative ventral bundles occur in the alternate position in the Tricyrteae and putative placental bundles in the opposite. position in the Petrosavieae. The dichtomously branched stigma in each carpel of the Tricyrteae is supplied by a bifurcated dorsal bundle.     

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