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％。     

高效诱导甜菜再生植株的研究

研究了栽培甜菜(Beta vulgaris L.)4倍体品系405叶柄外植体的离体培养。成功地建立了一套高频率诱导再生芽的程序。外植体取自生长在改良MS(MSB)附加BA和NAA或者单加BA的培养基中。经过30d以上预培养后的幼苗叶柄,在MS附加BA 1．0mg／L或NAA0．3mg／L,Bal．0mg／L培养基上直接诱导再生芽,并发育成苗．诱导频率最高可达51．3％。在1／2MS(MS培养基大量元素减半)附加NAA0．5～1．0mg／L的培养基上诱导生根．这一程序为甜菜扩大繁殖和遗传转化提供了一个良好的试验系统。     

球子蕨孢子的无菌繁殖

以球子蕨成熟孢子为外植体,研究了不同激素及浓度对其孢子萌发、愈伤组织诱导、丛生芽分化及生根的影响。结果表明：孢子萌发最适培养基为1／2MS＋2％蔗糖,20d后萌发率达55．7％;诱导愈伤组织的最适培养基为MS＋0．5mg·L-1 KT＋0．5mg·L～2,4-D,诱导率达36％,愈伤组织为绿色颗粒状;颗粒状愈伤组织在不添加激素的MS培养基中即可生长出大量丛生芽,转化率可达49．3％;低浓度（0．2mg·L-1）的IAA可有效促进幼孢子体苗生根。     

宿根福禄考离体快速繁殖的研究

以带芽茎段为外植体,MS为基本培养基,研究了不同激素组合对宿根福禄考离体快速繁殖的影响。试验结果表明,不同培养阶段的适宜培养基为：（1）启动培养基：MS＋6-BA1．0mg／L＋NAA 0．1mg／L;（2）继代增殖培养基：MS＋6-BA 1．0mg／L＋NAA 0．3mg／L,月增殖倍数可达7．4;（3）生根培养基：1／2MS＋IBA 0．2～0．5mg／L,生根率高且根粗壮。试管苗移入田间20d后成活率可达92％。     

柠檬马鞭草快速繁殖技术研究

选择柠檬马鞭草带腋芽的幼嫩茎段为外植体进行快速繁殖。结果表明,腋芽诱导的最适培养基是MS基本培养基附加6-BA0.5～1.0mg／L和IBA0．1～0．3mg／L．外植体腋芽能正常萌发生长,并迅速进入增殖状态,20d转接1次,增殖倍数存3倍以上,最适生根培养基是1／2MS基本培养基附加IBA0．5mg／L,诱导生根率达99％。将生根苗移入苗盆。30d的成活率在85％以上。     

小叶锦鸡儿的组织培养和快速繁殖

选用小叶锦鸡儿茎段为材料进行组织培养和快速繁殖,结果表明,芽诱导的最适培养基是MS基本培养基附加6-BA0．5mg／L和IAA0.01mg／L,最适生根培养基是1／2MS基本培养基附加IAA0．5mg／L,诱导生根率达86％．再生植株移人大田,15d后成活率在98%以上。     

丹参离体微繁技术研究

以丹参(Salvia miltiorrhiza Bunge)离体幼茎、叶、叶柄为外植体,对其丛生芽、不定芽的诱导和增殖、生根、移栽等方面进行系统研究,探讨了有关丹参的离体快速微繁技术。试验表明：MS 6-BA1．0mg／L是诱导初代培养的芽产生丛生芽的最佳培养基,其诱导生芽率为100％,丛生芽增殖的最佳培养基为MS 6-BA1．0mg／L NAA0．01mg／L;以叶为外植体,用MS 6-BA 0．5～2．0mg／L诱导不定芽可取得较好效果,其诱导生芽率为100％,不定芽增殖的最佳培养基为MS 6-BA1．0mg／L,其增殖倍数达24倍;诱导生根较好的培养基为1／2MS 0．1mg／L IBA,移栽先水培再土培,成活率可达100％。     

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。     

扁桃优良砧木离体快繁

对扁桃优良砧木“Hansen”侧芽进行离体快繁研究,结果表明：外植体取材时间不同,成活率差异明显,以春季芽即将萌动的3月下旬为最佳时间,在MS 6-BA1．0mg／L GA30．2mg／L培养基上诱导芽萌发,萌发率在75％以上;以MS 6-BAl．5mg／L IAA0．1mg／L进行芽的增殖培养效果最好;1／2MS IBA0．5mg／L诱导生根,并给以黑暗预处理可使生根率达85％以上,每株生根数量多,根系质量好;采用分步炼苗移栽,提高了小苗成活率,有利于小苗后期生长。     

古巴兰的茎段原球茎诱导与植株再生的研究

试验以古巴兰幼嫩芽体为外植体,通过原球茎诱导途径,建立快速高效的古巴兰再生体系。结果表明：最适宜的诱导茎段和叶片原球茎的培养基分别为MS＋5．0mg／L6-BA＋1．5mg／LNAA和MS＋2．0mg／L6-BA＋1．5mg／LNAA;诱导出的原球茎在MS＋1．5mg／L6～BA＋0．5mg／LNAA培养基上继代最好;在MS＋1．0mg／L6-BA＋0．5mg／LNAA的培养基上能分化出不定芽苗;再生的植株在MS＋6．0mg／L6-BA＋1．0mg／LNAA的培养基上能实现增殖和复壮;最适宜的生根培养基为1／2MS＋0．1mg／LNAA。     

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.     

鸡传染性法氏囊病病毒研究进展

传染性法氏囊病(Infection bursal disease, IBD)是由鸡传染性法氏囊病毒(Infectious bursal disease virus, IBDV)引起的鸡和火鸡的一种高度接触性传染病,给世界各国的禽养殖业带来了巨大损失.自IBDV发现至今新的变异株不断出现,分子结构的改变导致病毒致病力的改变及宿主对疫苗应答的改变,使得传统的疫苗已不能控制其流行,因此各国学者对其基因组结构和功能进行了广泛深入的研究,并积极研制新型有效的疫苗以达到防治的目的.     

Development of a Novel Reverse Transcription Loop-Mediated Isothermal Amplification Method for Rapid Detection of SARS-CoV-2

In conclusion, the novel visual RT-LAMP assay is a simple, rapid, and sensitive approach for detection of SARS-CoV-2, and it is ready for application in primary care and community hospitals or health care centers, and even patients' own houses in response to the current SARS-CoV-2 epidemic because the assay does not require sophisticated equipment and skilled personnel. Furthermore, it is also ready to be used in fields for screening samples from wild animals and environments to facilitate the identification of potential intermediate hosts that mediate the cross-species transmission of SARS-CoV-2 from bats to humans.     

Perinatal Vertical Transmission of Chikungunya Virus in Ruili,a Town on the Border between China and Myanmar

正Dear Editor,Chikungunya virus (CHIKV), an arbovirus in the family of Togaviridae, genus Alphavirus, is transmitted by the A.aegyptii or A. albopictus mosquito, and causes disease in humans characterized by fever, rash, and arthralgia (Silva and Dermody 2017; Suhrbier 2019). It was first reported in 1953 in Tanzania, and caused only a few outbreaks and sporadic cases in Africa and Asia in last century. However, in the epidemic in 2004, CHIKV acquired mutations that conferred enhanced transmission by the A. albopictus mosquito(Schuffenecker et al. 2006). Since then, it has successively caused outbreaks in Africa, the Indian Ocean, South East Asia, the South America, and Europe (Zeller et al. 2016).