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关键词： 铁皮石斛   生物信息学   基因组   内生菌  

摘要： 铁皮石斛为兰科多年生附生草本植物，具有观赏价值和广泛的药用功效，被称为“中华九大仙草”之首。本文以云南普洱铁皮石斛为材料，结合第二代Illumina HiSeq2000测序技术和第三代PacBio测序技术，得到contigN50=25.1kb，scaffoldN50=76.4kb的基因组草图，所有的测序量合计覆盖超过了铁皮石斛基因组94%的序列，功能注释了铁皮石斛大约97.56%的蛋白质编码基因。经分析发现，兰科植物具有完整的花序基因集，而铁皮石斛相对其他单子叶植物，具有独特的花序基因。同时，在基因家族扩张收缩分析中，我们发现，与真菌共生和抗旱性相关的基因家族发生了明显扩增。通过分析铁皮石斛药用成分生物合成途径，我们发现与多糖合成相关的SPS和SUSY基因发生大规模的复制，而铁皮石斛生物碱合成途径可以从已有的研究结果基础上延伸到16-epivellosimine的合成。本文不仅针对铁皮石斛基因组组装尝试了新的大型复杂基因组组装方法，同时也针对铁皮石斛内生菌、组培快繁技术等进一步研究，为今后研究兰科植物的进化、石斛的药用成分分析、铁皮石斛指纹图谱的建立及其潜在的基因育种奠定了基础。

关键词： Loranthus parasiticus   Scurrula parasitica   Loranthaceae   Mistletoe   Biological Activity   Coriaria Lactone   Review  

摘要： Loranthus parasiticus Merr (L. parasiticus) is a member of Loranthaceae family and is an important medicinal plant with a long history of Chinese traditional use. L. parasiticus, also known as Sang Ji Sheng (in Chinese), benalu teh (in Malay) and basokisei (in Japanese), is a semiparasitic plant, which is mostly distributed in the southern and southwestern regions of China. This review aims to provide a comprehensive overview of the ethnomedicinal use, phytochemistry and pharmacological activity of L. parasiticus and to highlight the needs for further investigation and greater global development of the plant's medicinal properties. To date, pharmacological studies have demonstrated significant biological activities, which support the traditional use of the plant as a neuroprotective, tranquilizing, anticancer, immunomodulatory, antiviral, diuretic and hypotensive agent. In addition, studies have identified antioxidative, antimutagenic, antiviral, antihepatotoxic and antinephrotoxic activity. The key bioactive constituents in L. parasiticus include coriaria lactone comprised of sesquiterpene lactones: coriamyrtin, tutin, corianin, and coriatin. In addition, two proanthocyanidins, namely, AC trimer and (+)-catechin, have been recently discovered as novel to L. parasiticus. L. parasiticus usefulness as a medicinal plant with current widespread traditional use warrants further research, clinical trials and product development to fully exploit its medicinal value.

关键词： 高中生物学   校园绿化   生活习性   动植物  

摘要： 学校是培养和造就社会主义建设者和接班者的重要场所。因此,搞好校园绿化,在现代社会发展中,对创建文明校园,优化育人环境,有着特殊的现实意义。可以这样说,一个学校的校园绿化美化程度,直接反映了该校的精神文明和物质文明水平。国家教委、全国绿化委员会在《关于开展校园绿化和营建学校林的通知》中明确要求:"把学校建成树木葱茏,花草满园,宁静舒适的环境,有利于改善师生生活、学习和工作条件,也有利于激发学生热爱

关键词： Polyploidy   Reproductive ecology   Bulbils   Trade-off   Phenotypic correlation   Seeds  

摘要： It has been proposed that plant species cytotypes commonly exhibit altered morphology, reproduction, geographic and ecological distributions. We studied phenotypic variation in height, sexual (flowers, seeds) and asexual (aerial bulbils) reproduction in natural populations and in the conditions of a common garden of three cytotypes (2n = 4x, 5x, 6x) of the bulbous geophyte Allium oleraceum in the Czech Republic. Additionally, we compared the germination and dormancy of seeds and bulbils to determine whether propagules have different ecological roles. The pattern of morphological differentiation observed between cytotypes under natural conditions was similar to that observed under common garden conditions, suggesting that variability in morphological characteristics appears to be associated with ploidy levels. We revealed differences in size and sexual and asexual production between A. oleraceum cytotypes, but with wide overlap among cytotypes, suggesting a limited possibility of the studied traits to reliably distinguish between cytotypes. Tetraploids and pentaploids were rather similar;they were taller and produced more flowers than hexaploids, which were mostly flowerless (mean <0.7 flower/plant). All cytotypes were able to produce viable seeds, but their numbers were extremely low, usually less than 3 seeds per inflorescence;clonal reproduction via aerial bulbils dominates in all cytotypes (flower:bulbil ratio <0.5), with tetraploids producing more but lighter bulbils than other cytotypes. The seed: ovule ratio was low (<0.1) in all cytotypes, although hexaploids reached higher values than other cytotypes. Bulbils germinated better (means >80%) than seeds in all cytotypes, with pentaploid bulbils showing the highest germination (mean 90.5%). The cytotypes did not differ in seed germination (range of means 73.4%-76.3%). About 6% of seeds did not germinate but were still viable at the end of the experiment, while all non-germinated bulbils of all cytotypes had rott

关键词： 植物生物学   领域   中国细胞生物学学会   中国遗传学会  

摘要： 为展现我国植物生物学研究的最新成果,促进科研人员、研究生之间的交流与合作,中国植物学会、中国细胞生物学学会、中国作物学会、中国遗传学会、中国植物生理与分子生物学会联合组织【2014年全国植物生物学大会】。这是国内植物生物学领域水平高、规模大、影响深远的学术盛会。本次会议将于2014年9月11日—14日在河南开封召开。大会将邀请植物生物学领域著名专家和近年来崭露头角的中青年学者作学术报告、并提供充足的墙报和最新科学仪器展

摘要： Vangueria madagascariensis (VM), consumed for its sweet-sour fruits, is used as a biomedicine for the management of diabetes and bacterial infections in Africa. The study aims to assess the potential of VM on alpha-amylase, alpha-glucosidase, glucose movement, and antimicrobial activity. The antioxidant properties were determined by measuring the FRAP, iron chelating activity, and abilities to scavenge DPPH, HOCl, (OH)-O-center dot, and NO radicals. Leaf decoction, leaf methanol, and unripe fruit methanol extracts were observed to significantly inhibit alpha-amylase. Active extracts against alpha-glucosidase were unripe fruit methanol, unripe fruit decoction, leaf decoction, and ripe fruit methanol, which were significantly lower than acarbose. Kinetic studies revealed a mixed noncompetitive type of inhibition. Leaf methanolic extract was active against S. aureus and E. coli. Total phenolic content showed a strong significant positive correlation (r = 0.88) with FRAP. Methanolic leaf extract showed a more efficient NO scavenging potential and was significantly lower than ascorbic acid. Concerning (OH)-O-center dot-mediated DNA degradation, only the methanol extracts of leaf, unripe fruit, and ripe fruit had IC50 values which were significantly lower than alpha-tocopherol. Given the dearth of information on the biologic propensities of VM, this study has established valuable primary information which has opened new perspectives for further pharmacological research.

关键词： CLIMBING plants   RESEARCH   LEAVES -- Anatomy   HOST plants  

摘要： The article focuses on a study by researchers Ernesto Gianoli and Fernando Carrasco-Urra in the 'Current Biology' as of May 2014, according to which the vine Boquila trifoliolata adapt nine leaf features including shape, colour and size in order to mimic the leaves of different host species.

关键词： 耧斗菜族   传粉生物学   繁育系统   花部特征   适应性进化  

摘要： 被子植物的花部特征具有丰富的多样性,而这种多样性产生的原因,即植物花部特征的进化机制,一直是进化生物学的重要命题之一。本研究以毛莨科耧斗菜族(Tribe Isopyreae, Ranunculaceae)的三种植物无距耧斗菜(Aquilegia ecalcarata Maxim.)、天葵[Semiaquilegia adoxoides (DC.) Makino]和距瓣尾囊草(Urophysa rockiiUlbr.)为研究材料,使用繁育生物学和传粉生物学的通用方法,以确定这些植物的繁育系统、分析其花部特征与传粉者的适应关系,并在此基础上讨论传粉者在花部特征尤其是花瓣特征进化中的作用。主要结果包括： 1)距瓣尾囊草以异交为主、自花授粉可育。其主要传粉者是东方蜜蜂(Apis cerana)和宽跗食蚜蝇属一种。其中东方蜜蜂是一种吸蜜传粉者,宽跗食蚜蝇仅取食花粉,而前者具有较高的传粉效率。距瓣尾囊草花瓣的花蜜距长度和径向宽度与东方蜜蜂口器的长度和宽度相适应。耧斗菜族花瓣一般与其吸蜜传粉者的口器相适应。当多种传粉者同时存在时,其花瓣特征可能更倾向于跟传粉效率较高的传粉者相适应。 2)天葵以自交为主,兼性异交。这样的繁育系统可能与其初春开花而传粉者不稳定有关。其主要传粉者是准蜂科一种(Melittidae sp.)。准蜂科昆虫以天葵的花蜜为食,但其访花频率极低。 3)无距耧斗菜在自然状态下以异交为主。其开花的过程中,通过雄雌蕊群空间以及生长发育差异,有效避免了自发自交的发生,对传粉媒介的依赖性较高。其主要传粉者为实蝇科一种(Tephritidae sp.)和宽跗食蚜蝇属一种(Platychirus sp.)。两种昆虫均仅以无距耧斗菜的花粉为食。无距耧斗菜的花瓣无距(或短距),没有泌蜜组织,不分泌蜜汁,可能与吸蜜传粉者的丢失有关。吸蜜传粉者在耧斗菜族花瓣进化的过程中扮演着重要的角色。 4)通过对耧斗菜族人字果属一支花瓣可能的进化过程进行推演,我们发现传粉者转换(包括传粉者类型的改变和传粉者的丢失)可能是推动这一支花瓣进化的关键因素。

关键词： 桔小实蝇   成虫   温度   寄主   产卵前期   性成熟   寿命   产卵量  

摘要： 观察研究了温度和寄主水果对桔小实蝇Bactrocera dorsalis(Hendel)成虫主要生物学参数的影响。结果如下:(1)寄主植物对桔小实蝇成虫的产卵前期影响无明显差异,而温度明显影响产卵前期。随温度增高,产卵前期逐渐缩短。取食杨桃的桔小实蝇雌虫在15℃、20℃、25℃、30℃、35℃下的产卵前期分别是41.1、29.1、13.8、12.9、15.6 d;(2)温度对桔小实蝇雄虫性成熟时间有明显影响。在温度15℃、20℃、25℃、30℃、35℃下,桔小实蝇雄成虫的性成熟时间为21.4、15.7、12.8、1 1.5和10.8 d;(3)不同温度和寄主水果条件下成虫寿命也不同,从较低温时的140-190 d缩短到高温时的34-37 d;(4)不同的寄主植物对桔小实蝇成虫的产卵量影响较大,一般取食芒果和番石榴的雌虫产卵量显著高于其他几种水果。在25℃温度下,取食芒果、番石榴、香蕉、枇杷、青枣、杨桃、柑桔的桔小实蝇雌虫的产卵量分别是1634.3、1520.6、1309.1、1019.8、983.3、966.3和912.9粒/雌;(5)雌成虫性成熟并交配后开始产卵,2-3 d进入产卵盛期。分别建立了以柑桔和番石榴为食的幼虫发育成的桔小实蝇成虫日产卵量(粒)随羽化时间(d)变化的模型为:Y(fecundity)=-3.524+0.707T-0.00679T2和Y(fecundity)=-20.104+1.9827-0.0203 T2;(6)推迟供给寄主明显影响桔小实蝇雌成虫的产卵量,推迟0、5、10、15、20、25 d供给寄主,取食杨桃的桔小实蝇雌虫在25℃下的平均产卵量分别为968.5、736.6、710.5、658.3、644.1和576.3粒/雌。

关键词： 木兰科   杂交过程   生殖生物学特性   遗传学规律   新品种选育  

摘要： 开展杂交育种，选育新品种，在美化环境、保护野生资源和恢复植被上有重要的意义。本论文对木兰科植物不同杂交组合的杂交过程和杂交后代的生殖生物学特性和遗传学规律进行研究及选育新品种。研究异种花粉在柱头上的萌发、花粉管在花柱内的生长过程、进入胚囊及双受精的整个过程；研究杂交后代小孢子发生及雄配子体发育，特别是不同倍性亲本之间杂交后代减数分裂过程中的染色体行为，揭示杂交后代生殖生物学特性和遗传规律，同时为木兰科植物杂交育种工作提供了可靠的理论基础和成熟有效的技术措施。研究内容和结果如下： （1）杂交组合A（Magnolia liliflora（♀）×Michelia yunnanensis（♂））的研究结果显示：具有较高的杂交亲和性，云南含笑花粉落在紫玉兰的柱头上3个小时即开始萌发，萌发率几乎达100%，10h的材料即可明显看到花粉管进入花柱道并且汇成一束，3d的材料即可看到花粉管明显已经进入胚囊。 （2）杂交组合B（Magnolia liliflora（♀）×Michelia doltsopa（♂））为不同倍性亲本属间杂交，染色体数目为2n=3x=57，通过压片法对其杂交后代减数分裂过程进行研究，发现存在较多异常现象：后期I出现染色体桥和不均等分离；在中期I、后期I、中期II、后期II出现滞后染色体；四分体时期出现断桥、不均等分裂等。采用悬滴培养法进行花粉离体萌发实验，人工气候箱中25℃恒温培养3h后观察花粉在培养基上不会萌发，16h后观察花粉粒破裂；释放出内含物。花粉粒大多数为破损，干瘪，哑铃形，形状大小差别较大。采用冰冻切片法研究杂交组合B的杂交后代小孢子发生及雄配子体发育，结果表明：花粉为四囊型，花药壁5-7层，四分体排列方式为左右对称型，小孢子形成时胞质分裂方式为修饰性同时型，成熟花粉粒为二细胞型。减数分裂过程异常、小孢子母细胞收缩、细胞核和细胞质粘连，分裂不同步、小孢子粘连、小孢子过度收缩“骨化”、绒毡层退化迟延等异常现象将会导致花粉败育，进一步影响有性生殖的有效性。致使杂交组合B花粉败育的原因很多，其中最重要的原因是减数分裂异常、小孢子发生及雄配子体发育异常。 （3）杂交组合C（Michelia sphaerantha（♀）×Michelia crassipes（♂））的杂交后代染色体数目为2n=2x=38，采用压片法研究减数分裂过程表明：减数分裂过程正常，减数分裂中期Ⅰ基本构型为19个二价体。采用悬滴培养法进行花粉离体萌发实验，发现在人工气候箱中25℃恒温培养3h即开始萌发长出花粉管，16h后观察花粉管不断伸长。花粉粒大小均一，形状规则。 （4）对已经开花的杂交种的园艺性状进行观察和记录，并从中筛选出了1个园艺性状优良的新品种，该品种选自（Magnolia liliflora（♀）×Michelia yunnanensis（♂））—杂交组合A。 （5）对杂交组合D（（Michelia floribunda×Michelia yunnanensis）（♀）×Micheliamaudiae（♂））和杂交组合E（（(Michelia crassipes×Michelia yunnanensis）（♀）×Michelia maudiae（♂））杂交多次均没有获得种子，种子发育到一定阶段后就停止生长。