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1.
曾青  强胜 《应用生态学报》2002,13(7):833-836
通过盆栽试验,研究了真菌自身生物学特性、杂草生长状况和环境因素等对胶孢炭疽菌婆婆纳专化型菌株QZ-97a侵染波斯婆婆纳的影响。结果表明,子叶期和衰老斯波斯婆婆纳感病性最强;培养7-14d后的孢子侵染力最强;病害发生的最佳温度范围是15-25℃;在保湿2-3d的条件下,露期中间的光照时间越短,病害发生越严重;保湿也可通过添加玉米粉和黄粉等介质来解决;达到理想致病效果的该菌株孢子悬浮液浓度必须在10^7个.ml^-1以上,由此可见,菌株QZ-97a在波斯婆婆纳发生时期的环境条件下可有效控制该杂草。  相似文献   

2.
中国境内睫毛婆婆纳生态特征研究   总被引:3,自引:0,他引:3  
睫毛婆婆纳是地中海周缘地区的重要农田杂草 ,对其个体生理生态学和种群生态位研究表明 ,睫毛婆婆纳种子在通气性良好的土壤中具有高的萌发率 ;含水量为 1 0~2 0 %的土壤 ,有利于其种子萌发 ;种子萌发对 pH值要求并不严格 ;低温能促进其种子萌发 ;光合作用特征与波斯婆婆纳比较接近 ,属于耐阴植物 ;种子呼吸强度比同属其它杂草略低 ;种群在南京地区的实际生态位宽度比同属的波斯婆婆纳、婆婆纳要小 .生态位重叠值计测表明 ,睫毛婆婆纳与同属的两种杂草有最为相似的生态要求 .  相似文献   

3.
本文建立了藏药婆婆纳药材的薄层鉴别方法。采用单因素试验方法,对影响婆婆纳对照药材的薄层色谱因素进行系统考察,筛选出最佳的薄层色谱条件。该薄层鉴别条件吸附剂:硅胶G薄层板;展开剂:环己烷-丙酮(6∶4);显色剂:10%硫酸乙醇溶液;显色条件:110℃烘箱中加热至斑点显色清晰,日光下检视,所得的薄层色谱,斑点清晰,分离度好。该方法分离度高,重现性好,简便,可用于婆婆纳的质量控制。  相似文献   

4.
报道贵州省2个新记录属——假婆婆纳属(Stimpsonia Wright ex A. Gray)和山涧草属(Chikusichloa Koidz.),以及3个新记录种假婆婆纳(Stimpsonia chamaedryoides Wright ex A. Gray)、山涧草(Chikusichloa aquatica Koidz.)和广东西番莲(Passiflora kwangtungensis Merr.)。三种植物均发现于贵州黎平太平山州级自然保护区,凭证标本存放于中国科学院华南植物园标本馆(IBSC)和中国科学院植物研究所标本馆(PE)。文中描述3种植物的主要特征,并讨论了新发现的广东西番莲叶片变异情况。  相似文献   

5.
邵建章 《植物研究》1989,9(3):73-73
本文发表了假婆婆纳一新变型,即红花假婆婆纳Stimpsonia chamaedryoidesWright.f.rubriflora J.Z.Shao  相似文献   

6.
匍匐婆婆纳'霍尔特夫人'的组织培养和快速繁殖   总被引:1,自引:0,他引:1  
1 植物名称 匍匐婆婆纳‘霍尔特夫人’(Veronica prostrata L.‘Mrs.Holt’)。  相似文献   

7.
以阿拉伯婆婆纳为实验材料对初中生物学"探索水分在茎内的运输途径"、"探索蒸腾作用散失水分"、"观察叶片的结构"和"探索植物的无性繁殖的应用——扦插"等实验进行改进,提高课堂教学效果。  相似文献   

8.
赵一之 《植物研究》2002,22(4):385-386
发表新疆婆婆纳属一新种  相似文献   

9.
大花哥纳香叶的化学成分   总被引:5,自引:0,他引:5  
从番荔枝科哥纳香属植物大花哥纳香(Goniothalamusgriffithii)的叶中分离到4个化合物griffithineA(I),goniodiolmonoacetata(Ⅱ),β-sitosterol(Ⅳ)其中(I)为新化合物。  相似文献   

10.
为明确婆婆纳(Veronica didyma)抗黑色素瘤活性部位及物质基础,该研究采用CCK8法评价了婆婆纳乙醇提取物4个萃取部位(石油醚层、乙酸乙酯层、正丁醇层、水层)乙醇提取物及单体化合物对黑色素瘤细胞株(B16和A375)细胞的增殖抑制作用,并使用植物化学方法和技术对活性部位的化学成分进行系统分离纯化。结果表明:(1)乙酸乙酯萃取部位(ethyl acetate extract,PPNE)较其他样品有更好抑制B16细胞和A375细胞增殖的作用,其半抑制浓度(IC50)值分别为0.177 mg·mL-1(B16)、2.826 mg·mL-1(A375)。(2)从活性部位PPNE中得到7个单体化合物,即对羟基苯甲醛(1)、胡黄连苷II(2)、isoscutellarein 7-O-(6?-oacetyl)-β-allopyranosyl (1?→2″)-β-glucopyranoside(3)、3′-hydroxyl-4′-O-methylisoscutellarein 7-O-[6?-O-acetyl-β-D-allopyranosyl-(1→2)-β-D-glucopyranos...  相似文献   

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It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.  相似文献   

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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.  相似文献   

18.
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.  相似文献   

19.
肝癌中HBV和HCV基因和抗原的分布及意义   总被引:1,自引:0,他引:1  
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  相似文献   

20.
For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment.  相似文献   

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