几种植物精油及单体对栗疫病病菌的抑制作用

栗疫病 ( Cryphonectria parasitica)是一种世界范围的林木病害 ,2 0世纪上半叶不到50年的时间里栗疫病将美洲栗几乎毁灭 [1 ] ,欧洲栗也曾遭受巨大损害[2 ] ,中国板栗一向被认为是最抗栗疫病的 [3] ,但由于栽培制度的改变、种质资源的频繁交流、单一化品种的应用等原因 ,原有相对平衡的寄主——病原物系统被迅速打破 ,我国部分地区的栗疫病已经造成了较大损失[4] 。由于欧洲栗的栗疫病菌群体遗传结构较为单一 ,欧洲人利用含有ds RNA的低毒力栗疫病菌菌株对欧洲栗的栗疫病进行生物防治取得了成功 [5] ,但因为这种 ds RNA一般只在具有营养…     

江西板栗品种调查

板栗是一种木本粮食,发展板栗生产对改善人民生活、换取外汇和老区脱贫致富有重要的意义。庐山植物园与省有关单位从1971—1988年,对江西板栗地方品种选育、推广嫁接技术、普及丰产栽培技术、引进外省良种、建立板栗生产基地等,做了大量工作。通过地方品种资源调查,基本上摸清了江西板栗品种资源及其分布。并初步整理出:薄皮大油栗、灰黄油栗、中秋栗、桂花栗、紫油光栗、白毛栗、金坪矮垂栗等品种或株系。通过引种对比试验,筛选     

抗栗瘿蜂优良锥栗品种的初步选择研究

通过调查统计建瓯市水源乡,采穗圃中8个锥栗品种的每株虫瘿数和单株产量,以方差分析和多重比较法进行分析,初步筛选了抗栗瘿蜂的锥栗品种,研究结果显示,蔓榛和中榛子是抗栗瘿蜂的优良品种,生产上可作为栗瘿蜂综合治理的推广品种。     

欧美药用植物(三)

本品为七叶树科植物欧洲七叶树(Aesculushippocastanum)的种子，叶和树皮也入药。又名：马栗、欧马栗。英文名：Horse Chestnut。     

七叶皂苷的药理作用与临床应用

娑罗子为七叶树科植物欧洲七叶树(Aesculus hippocastannum)、日本七叶树(Aesculus turbinata Blume)和中国天师栗(Aesculus Wilsonii Rehd)的果实或种子。欧洲七叶树,又名欧马栗(horse chestnut),其种子和幼枝的外皮可入药,在欧洲应用广泛,早在18世纪即用于解热,19世纪后期可用于治疗痔疮。七叶皂苷是从娑罗子(七叶树种子)中提取的主要活性成分,属于三萜皂苷类药物。它具有抗渗、消肿、改善血液循环、增加静脉张力、抑制胃排空、清除活性氧和抗肿瘤作用。临床上可广泛应用于慢性静脉功能不全,痔疮、水肿、哮喘等。本文对七叶皂苷的药理作用及其临床应用进行综述。     

基于mtDNA COI基因的系统分析表明栗属植物上隐藏瘿蜂种的存在

本研究利用mtDNACOI基因的部分序列对11种群不同寄主的栗瘿蜂Dryocosm us kuriphilus Yasumatsu遗传多态性进行了分析。在获得的660bp的序列中,变异位点(V)80个,包括简约信息位点(Pi)15个和自裔位点(Si)65个。T、A、C、G平均含量分别为30.6%、43.3%、13.7%和12.4%,A+T平均值为73.9%,远高于G+C的26.1%,表现出明显的A+T偏向性。为害锥栗的六步溪、大围山种群与茅栗、板栗的不同地理种群,以及为害欧洲栗的意大利Piedmont种群之间,基因序列完全一致或者遗传距离在0.3%以内,无论是NJ系统树还是UPGMA系统树均聚合在同一分支内,亲缘关系较近。而为害锥栗的采自福建省建瓯市水源镇的水源种群、福建省周宁县纯池镇的纯池种群,与其它各栗瘿蜂种群的基因序列差异较大,遗传距离均大于2%,在NJ和UPGMA系统树中水源种群和纯池种群均聚合为一单独的分支,与其它种群形成的分支互为姊妹分支。据此我们认为水源种群和纯池种群很有可能属于不同的物种,有进一步研究的必要。     

我国和欧美洲栗疫菌低毒株dsRNA同源性比较

在发现我国栗疫苗(Cryphonectria parasitica=Endothia parasitica)含dsRNA低毒力菌株基础上,分别以国内菌株EpC140和EpC32、欧洲低毒株Ep713的dsRNA为探针,同欧洲、美洲及亚洲低毒力菌株dsRNA进行分子杂交,结果表明亚洲株同欧洲株之间有序列同源性,同美洲株之间无序列同源性.     

中国栗疫病菌群体遗传结构的空间自相关性分析

应用空间自相关分析方法对中国栗疫病菌17个居群RAPD遗传变异的空间结构进行研究,以探讨栗疫病菌居群遗传变异的分布特征及其形成机制。结果表明：中国栗疫病菌居群缺乏空间结构,绝大多数RAPD位点变异为随机分布的空间模式,但部分位点表现出渐变、斑块和双向渐变的非随机分布模式,又显示了一定的空间结构。推测其形成原因可能是长距离的基因流、人类活动、地理隔离以及栗疫病菌本身的繁殖特性综合作用的结果,并依据部分位点呈单向渐变的模式推测西南地区为中国栗疫病菌的起源中心。     

瓜栗长足象的初步研究

<正> 瓜栗长足象Alcidodes sp.是瓜栗Pachiramacrocarpa、水瓜栗P.aguaitica、攀枝花Go-ssampinus malabrica、油梨Persea americana、可可Theobroma cacao、杧果Mangifera indica、古巴苹婆Sterculia cubense等多种热带经济林木和果树的重要害虫。幼虫钻蛀当年萌主的幼     

甘肃莲花山自然保护区栗背岩鹨的繁殖记录和孵卵节律

2002年5-7月,在甘肃莲花山自然保护区对栗背岩鹨的繁殖生态做了进一步观察。记录了栗背岩鹨卵的大小、形状、颜色,产卵过程和孵卵节律。栗背岩鹨孵卵期为15天,育维期为14天。     

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