单头亚菊的组织培养与快速繁殖

以单头亚菊茎段为外植体对其进行组织培养,MS为基本培养基,设置不同激素浓度配比。对实验结果进行观察分析,筛选出合适的配方。启动培养基为Ms＋0．5mg·L-16-BA＋0．01mg·L-1NAA。继代培养基MS＋O．75mg·L-1。6-BA＋0．01mg·L。NAA,可获得较高的增殖率。不定根最适诱导培养基为1／2MS＋O．15mg·L—IBA,生根率达87％以上,组培苗移栽成活率达98％。     

文采唇柱苣苔的组织培养与快速繁殖

以肉质叶为外植体,研究文采唇柱苣苔的组织培养和快速繁殖。结果表明：培养基MS＋6-BA 0.1 mg？L-1＋NAA 0.1mg？L-1适用于初代培养时的愈伤组织诱导和植株再生;MS＋6-BA 0.5 mg？L-1＋NAA 0.2 mg？L-1＋10%香蕉泥和MS＋6-BA 0.5mg？L-1＋NAA 0.5 mg？L-1＋10%香蕉泥分别适用于继代增殖及壮苗培养,60 d后的增殖系数分别为6.7和4.8;培养基MS适用于生根培养,培养30 d,生根率达100%。另外,对文采唇柱苣苔生根试管苗进行大棚移栽,移栽成活率约为94%。     

紫花亚菊（Ajania purpurea）的组织培养与快速繁殖

以紫花亚菊茎段为外植体对其进行组织培养,MS为基本培养基,设置不同激素浓度配比,对试验结果进行观察分析,筛选出适合的配方：启动培养基为MS＋6-BA0.5mg·L-1＋NAA0.01mg·L-1;继代培养基MS＋6-BA0.3mg·L-1＋NAA0.05mg·L-1,组培苗分化率高;不定根最适诱导培养基为：1/2MS＋IBA0.15mg·L-1,生根率达90%以上,组培苗移栽成活率达95%。     

蝴蝶兰的组织培养和快速繁殖

通过诱导残败花梗上的休眠芽萌发,以萌发的幼叶和去茎尖的茎段为外植体进行组织培养,建立了蝴蝶兰(Phalaenopsis amabilis Bl.)的无菌繁殖体系,并筛选出最佳培养基组成.诱导休眠芽萌发的最佳培养基为不加任何激素的MS0培养基;原球茎诱导的适宜培养基为MS 3.0 mg·L-1 6-BA 0.5 mg·L-1 ZT 30 mg·L-1柠檬酸和MS 5.0 mg·L-1 6-BA 30 mg·L-1柠檬酸 30%椰乳(CM),其中茎段的诱导效果明显优于叶片,诱导率达95%;诱导无菌苗生根的最适培养基为1/4 MS 1.0 mg·L-1 6-BA 0.1 mg·L-1 NAA,生根率可达79%.     

吊石苣苔的组织培养与快速繁殖

1植物名称吊石苣苔（Lysionotus pauciflorus Maxim.）,别名石矼豆、石吊兰。2材料类别幼嫩叶片。3培养条件（1）愈伤组织和不定芽诱导培养基：MS＋6-BA3.0mg·L-1（单位下同）;（2）增殖与继代培养基：MS＋6-BA3.0＋NAA0.1;     

菊芋组织培养快繁技术的建立

以菊芋带芽点的薯盘及带节的幼嫩茎段为外植体,MS为基本培养基,附加不同种类和浓度的生长调节物质,研究菊芋组织培养和快速繁殖的技术环节,最终筛选出最优技术参数组合,建立菊芋再生体系。试验结果表明：茎段外植体是理想的快速繁殖材料,正接（形态学下端向下）是最佳的接种方式。芽诱导最佳培养基为MS＋1.0mg·L-16-BA＋0.2mg·L-1IBA,诱导率为95%;继代增殖最适宜培养基为MS＋2.0mg·L-16-BA;壮苗培养最佳培养基为MS＋0.1mg·L-16-BA;生根适宜培养基为MS＋0.2mg·L-1NAA,生根率达100%;移栽成活率达95%,大田种植成活率达95%以上。     

桂林小花苣苔离体快速繁殖技术

对抗结核植物桂林小花苣苔（Chiritopsis repanda var.guilinensis）进行离体培养与快速繁殖技术研究。结果表明：桂林小花苣苔叶片外植体的最适初代诱导培养基为MS＋0.5mg·L^-16-BA＋0.05mg·L^-1IBA,pH8.0;最适继代增殖培养基为MS＋0.1mg·L^-16-BA＋0.05mg·L^-1IBA,pH6.0,繁殖系数7.0/35天;最适生根培养基为1/2MS＋0.2mg·L^-1NAA,pH6.0,生根率为93.6%。模拟桂林小花苣苔自然生境,在春季对生根试管苗进行大棚移栽,成活率达90%。根据上述快繁技术,理论上每株试管苗每年可繁殖桂林小花苣苔种苗46万株。     

白背三七的组织培养和高频再生

以白背三七不同生长时间的叶片及茎段作为实验材料,利用含有多种不同植物生长调节剂及其浓度配比的MS培养基分别诱导愈伤组织、不定芽和根,建立了组织培养和高频离体再生体系。结果表明：（1）最适外植体为生长15d的叶片和茎段;（2）诱导愈伤组织的最适植物生长调节剂及其浓度配比为0．5mg·L-1 2,4．D、0．8mg·L-1 6-BA和0．1mg·L～NAA,茎段和叶愈伤组织的诱导率分别为95．6％和97．8％;（3）诱导不定芽的最适植物生长调节剂及其配比为1．0mg·L-1 6-BA、0．2mg·L-1 NAA和0．1mg·L-1 TDZ,诱导率可达87．4％;（4）以MS＋0．2mg·L-1 NAA作为生根培养基可获得100％的生根率。将生长良好的的植株进行移栽,存活率可达95％。     

水杉愈伤组织诱导及植株再生

通过愈伤组织诱导器官发生途径,建立了水杉（Metasequoia glyptostroboides）的植株再生体系,探讨了不同外植体（种胚、幼叶切块、茎段、根段）和植物生长调节剂对不定芽直接再生和愈伤组织诱导器官发生的影响。结果表明：以种胚、无菌苗叶片、茎段和根作为外植体,在MS补加2,4-D、NAA和6-BA不同组合的培养基上都能诱导得到愈伤组织,其中种胚诱导愈伤组织效果最好,诱导率可达100%,茎诱导效果次之,诱导率为97.1%。诱导愈伤组织效果较好的培养基有：MS＋1.0mg·L-12,4-D＋0.5mg·L-16-BA、MS＋0.1mg·L-16-BA＋1.0mg·L-1NAA、MS＋0.5mg·L-16-BA＋1.0mg·L-1NAA、MS＋1.0mg·L-16-BA＋1.0mg·L-1NAA、MS＋0.5mg·L-16-BA＋2.0mg·L-1NAA、MS＋1.0mg·L-16-BA＋2.0mg·L-1NAA和MS＋0.5mg·L-12,4-D＋0.5mg·L-1NAA。以愈伤组织在MS培养基上植株再生效果最好,再生率为62.5%。     

‘香槟’月季的组织培养和试管开花诱导

本文对‘香槟’月季（80sachinensis‘Xiangbin’）的组织培养技术和诱导试管开花进行了研究。结果表明：以茎段为外植体能诱导获得无菌苗,适宜的启动培养基为MS＋6-BA1．0mg-L-1＋IBA0．1mg·L-1,幼芽继代增殖的最佳培养基是MS＋6．BA1．0mg·L-1。＋IBA0．1～0．2mg·L-1,诱导生根的适宜培养基为1／2MS＋NAA0．3mg·L-1,生根率达80．0％。诱导试管开花的适宜培养基为MS＋6．BA0．5mg·L-1＋NAA0．1mg·L-1最适宜的诱导试管开花的蔗糖含量是30g·L-1;在三角瓶中培养,试管花可以正常开放,在培养瓶中培养花芽不能正常开放;MS培养基中增加2倍磷的含量,可以提高花芽诱导率,为25．O％;诱导试管开花的最适培养条件为温度21℃,光照强度80～100μmol·m-2．s-1,光照时间16h—d-1。     

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).