一种崂山百合的离体快速繁殖技术

以崂山百合的鳞茎为外植体,通过植物组织培养技术成功获得了再生植株,建立了该植物的快速无性繁殖体系。整个组织培养过程分为芽的诱导、根的诱导和移栽三个阶段。适合芽诱导的最佳外植体是：鳞茎基部,最适培养基是：1／2MS＋0．5mg／LNAA＋0．8mg,LKT＋3％蔗糖。用于生根的最佳培养基是：1／2MS＋0．4mg/LIBA＋3％蔗糖。最适培养温度为25℃．不同基质对组培苗移栽的成活率有一定影响,其中在珍珠岩上的移栽成活率为98％。     

达摩兰组织培养适宜培养基的研究

以达摩兰的原种苗茎段为外植体进行组织培养研究,筛选出最适培养基(1)原球茎诱导:MS+6-BA 0.5 mg/L+NAA 1.0 mg/L+香蕉肉250 g/L;(2)丛生芽诱导:1/2 MS+6-BA 3 mg/L+NAA 2.0 mg/L+AC 2.5 g/L+蔗糖3%+香蕉肉200 g/L;(3)芽增殖:1/2 MS+6-BA 3 mg/L+NAA 2.0 mg/L+AC 2.5 g/L+蔗糖3%+香蕉肉150 g/L;(4)根诱导:1/2 MS+6-BA 0.3 mg/L+IBA 0.5 mg/L+NAA 0.5 mg/L+AC 2.5 g/L+蔗糖3%。采用珍珠岩、细石与树皮的混合物为培养基质,移栽成活率达95%以上。     

芥蓝组织培养研究

以登峰芥蓝为试材,取无菌苗的茎段、下胚轴为外植体分别进行组织培养研究。结果表明:MS+6-BA 3.0 mg/L+NAA 0.2 mg/L为下胚轴最适诱导培养基,MS+6-BA 5.0 mg/L+NAA 0.2 mg/L为带腋芽茎段最适诱导培养基;最适宜的不定芽增殖培养基为MS+6-BA 3.0 mg/L+NAA 0.2 mg/L;试管苗在1/2MS+NAA 0.1 mg/L+IBA 0.2 mg/L培养基中进行生根培养效果最好;经炼苗后组培苗移栽成活率达96.6%。     

不同生长调节剂对白芨无菌萌发及成苗影响

以八月中旬在五峰采集的白芨未成熟种子为外植体,通过植物组织培养技术,对白芨进行无菌播种,后通过丛生芽诱导及生根培养,以期得到的白芨组培苗,并对其进行炼苗。实验研究了植物生长调节剂对白芨无菌萌发率及其成苗的影响,总结了白芨各个生长阶段最佳的培养基组分。实验表明:白芨种子萌发最适培养基为:1/2 MS+1 mg/L NAA+2 mg/L 6-BA+3%蔗糖+0.7%琼脂,接种20 d后的种子萌发率为98%,萌发时间快而集中,出芽整齐一致;白芨丛生芽诱导最适培养基为:1/2 MS+1 mg/L NAA+1 mg/L GA3+0.2%AC+3%蔗糖+0.7%琼脂,接种20 d后白芨丛生芽诱导率为75%,苗基部产生丛生芽量较多,生长较快;白芨生根最适培养基为:MS+0.2 mg/L NAA+3%蔗糖+0.8%琼脂,接种20 d后白芨生根率为0.95%,苗根粗壮,长势好,且出苗整齐。该实验结果为白芨规模化生产提供了一定依据,在白芨资源利用和异地保护上具有重要意义。     

金黄花滇百合植株再生与离体快繁技术体系的建立

以金黄花滇百合(Lilium bakerianum var. aureum)的鳞片为外植体, 探讨不同部位外植体和不同配比的植物生长调节剂对愈伤组织诱导和植株再生的影响。研究结果表明, 鳞片诱导愈伤组织和不定芽的最适培养基为MS+1.0 mg∙L ^-16-BA+0.1 mg∙L ^-1NAA+30 g∙L ^-1蔗糖; 不定芽增殖的最适培养基为MS+0.5 mg∙L ^-16-BA+0.1 mg∙L ^-1NAA+30 g∙L ^-1蔗糖; 不定芽诱导小鳞茎的最适培养基为MS+1.0 mg∙L ^-1NAA+30 g∙L ^-1蔗糖; 小鳞茎膨大生根的最适培养基为1/2MS+0.01 mg∙L ^-1NAA+60 g∙L ^-1蔗糖。该研究为金黄花滇百合种质资源保护和快速繁殖提供了技术支撑。     

金黄花滇百合植株再生与离体快繁技术体系的建立

以金黄花滇百合(Lilium bakerianum var. aureum)的鳞片为外植体, 探讨不同部位外植体和不同配比的植物生长调节剂对愈伤组织诱导和植株再生的影响。研究结果表明, 鳞片诱导愈伤组织和不定芽的最适培养基为MS+1.0 mg?L ^-16-BA+0.1 mg?L ^-1NAA+30 g?L ^-1蔗糖; 不定芽增殖的最适培养基为MS+0.5 mg?L ^-16-BA+0.1 mg?L ^-1NAA+30 g?L ^-1蔗糖; 不定芽诱导小鳞茎的最适培养基为MS+1.0 mg?L ^-1NAA+30 g?L ^-1蔗糖; 小鳞茎膨大生根的最适培养基为1/2MS+0.01 mg?L ^-1NAA+60 g?L ^-1蔗糖。该研究为金黄花滇百合种质资源保护和快速繁殖提供了技术支撑。     

茎秆的第一节间离体再生空心菜

以空心菜(Ipomoea aquatica Forsk.)品种‘白骨柳叶’为材料,通过筛选植物外植体和调整培养基激素配比等方法,首次建立了茎秆第一节间为外植体的空心菜离体再生体系。结果表明,在MS基本培养上添加0.05%的植物组织培养抗菌剂PPM可获得大量空心菜无菌苗;植株子叶和下胚轴的切段均未诱导出不定芽,而茎秆第一节间为外植体能成功诱导出不定芽,诱导成功率为20%,最佳培养基配方为MS+1.0 mg/L 6-BA+0.1 mg/L IAA;不定芽诱导生根的最佳培养基配方为1/2 MS+0.1 mg/L NAA,生根率为100%。诱导成功后,将完整的再生苗移栽至基质土中,成活率可达100%。     

濒危物种绒毛皂荚组织培养快繁技术的初步研究

以绒毛皂荚(Gleditsia vestita Chun et How ex B.G.Li)种子为外植体,通过愈伤组织诱导、不定芽分化增殖、生根和驯化移栽,建立了绒毛皂荚组织培养的快速繁殖体系。结果表明:1)绒毛皂荚子叶和胚轴在MS+6-BA3.0 mg/L+KT 0.4 mg/L+IAA 0.3 mg/L培养基上同步诱导出愈伤和芽,愈伤组织诱导率达到90.5%,同步分化率高达77.9%;2)不定芽增殖的最佳培养基为1/2MS+6-BA 1.0 mg/L+IBA 0.3 mg/L+NAA 0.2 mg/L,培养20 d后,增殖倍数为4.0;3)MS+NAA 0.5 mg/L+IAA 0.25 mg/L条件下,生根率高达100%,且移栽后植株长势好,成活率达90%以上。     

茎杆的第一节间离体再生空心菜

以空心菜（Ipomoea aquatica Forsk.）品种‘白骨柳叶’为材料,通过筛选植物外植体和调整培养基激素配比等方法,首次建立了茎秆第一节间为外植体的空心菜离体再生体系。结果表明,在MS基本培养上添加0.05% 的植物组织培养抗菌剂PPM可获得大量空心菜无菌苗;植株子叶和下胚轴的切段均未诱导出不定芽,而茎秆第一节间为外植体能成功诱导出不定芽,诱导成功率为20%,最佳培养基配方为MS+1.0 mg/L 6-BA+0.1 mg/L IAA;不定芽诱导生根的最佳培养基配方为1/2 MS+0.1 mg/L NAA,生根率为100%。诱导成功后,将完整的再生苗移栽至基质土中,成活率可达100%。     

LA系列百合‘Eyeliner’花器官组培快繁技术研究

该试验以LA系列百合‘Eyeliner’花器官为外植体,通过不定芽直接诱导和愈伤组织再分化2种途径,建立了花器官组培快繁技术体系。结果表明:以花器官为外植体污染率接近于0;4种百合花器官诱导从易到难的顺序为花梗、花丝、子房和花柱;花丝易诱导愈伤组织,花梗易诱导不定芽,最适诱导培养基均为MS+1.0mg·L-1 6-BA+0.5mg·L-1 NAA;不定芽增殖最佳培养基为MS+2.0mg·L-1 6-BA+0.2mg·L-1 NAA,愈伤组织分化最佳培养基为MS+1.5mg·L-1 6-BA+0.2mg·L-1 NAA;诱导生根最佳培养基为MS+45g·L-1蔗糖;最佳炼苗方式为将组培苗封口放置在自然环境中3d,然后开口放置在自然环境条件下2d;当试管苗鳞茎大小为3.15cm时,移栽成活率最高;移栽最佳基质为草炭∶蛭石∶珍珠岩=2∶1∶1。     

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     

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.     

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