High sensitivity of seeds to water loss is a widespread phenomenon in the world's plant *** molecular basis of this trait is poorly understood but thought to be associated with critical changes in membrane *** pro...
详细信息
High sensitivity of seeds to water loss is a widespread phenomenon in the world's plant *** molecular basis of this trait is poorly understood but thought to be associated with critical changes in membrane *** profiled membrane lipids of seeds in eight species with varying levels of desiccation tolerance and found a close association between reducing seed viability and increasing phosphatidic acid(PA).We applied hydration-dehydration cycles to Arabidopsis seeds,that are normally desiccation tolerant,to mimic the onset of desiccation sensitivity with progression towards germination and examined the role of phospholipase D(PLD) in desiccation stressmigrated from the change,and that all desiccation--dehydration cycle improved significantly.-mediated PA formation modulates desiccation sensitivity as applying its inhibitor improved seed desiccation tolerance and its suppression in protoplasts enhanced survival under *** insights provided by comparative lipidomics enable us to propose a new membrane-based model for seed desiccation stress and survival.
Salvia,consisting of about 1000 species and diversity hotspots on five continents,is one the largest genus of *** 100 species of Salvia are native to East Asia(EA),making EA one of the three major biodiversity centers...
详细信息
Salvia,consisting of about 1000 species and diversity hotspots on five continents,is one the largest genus of *** 100 species of Salvia are native to East Asia(EA),making EA one of the three major biodiversity centers of the *** previous studies have suggested that EA Salvia are monophyletic,relationships within this lineage remain *** lack of phylogenetic clarity has hindered our ability to understand the biogeographic history,species diversity,and systematics of *** relationships inferred from five DNA markers strongly support the monophyly of EA *** a result of our analyses we propose a new classification system matching both molecular phylogenetic and morphological evidence,and recognize EA Salvia clade as a subgenus(Glutinaria) and subdivide the subgenus into eight ***,six distinct stamen types were observed within the EA *** type A,with two fully fertile posterior thecae,only occurs in ***,and is ostensibly plesiomorphic within EA *** morphology has apparently evolved in parallel within EA Salvia.
薇甘菊是菊科(Asteraceae)假泽兰属(Mikania)植物,为世界十大有害杂草之一。为了更好地适应入侵地的新环境,薇甘菊呈现出极强的表型可塑性,生长和繁殖的对策明显不同。这种表型可塑性在其成功入侵新环境的过程中起着关键作用,表观遗传变异应是其入侵和扩张的驱动力。为此,我们采用甲基化敏感扩增多态性技术(MSAP)对华南地区21个薇甘菊种群的表观遗传变异展开分析。结果表明:1.种群间存在显著的甲基化变异;2.种群内(86.5%)的表观遗传变异明显大于种群间(13.5%);3.表观遗传变异存在"isolation by distance"模式;4.0-50 m的范围内,种群在表观遗传变异水平上存在明显的空间自相关;5.鉴定出4个表观适应性位点,其中1个位点与Mn、Zn和P正相关,另外3个位点均与Bio12(年降水量)呈负相关;6.和遗传变异相比(He=0.079;Fst=0.18084),表观遗传变异存在较高的多样性和较低的遗传分化(He=0.084;Fst=0.12634)。7.生态位模型推断,薇甘菊最适分布区集中在广东广西南部以及台湾南部和东南部地区,Bio01(年平均温度)、Bio02(平均日间温度范围)、Bio06(最冷月最低温度)、Bio09(最干季平均温度)、Bio11(最冷季平均温度)和Bio18(最暖季降水量)对其分布起着关键性的作用。研究结果将为探究薇甘菊的入侵机制提供理论依据。
芒属(Miscanthus Andersson s.l.)植物由于其生物量高,耐受力强,多年生等优点在生物能源领域受到广泛关注。中国是芒属植物的分布中心,为开发和利用芒草提供了天然的种质资源。本研究开发了24个微卫星标记,对分布在中国的4个芒属物种(芒***、五节芒***、荻***、南荻***)100个天然群体进行群体遗传学和进化历史的研究,主要研究结果如下:1)中国的芒属植物首先划分为群I和群II两大支,群I可进一步划分为两部分(群Ia和群Ib),群II可进一步划分为3部分(群IIa,群IIb,群IIc)。结合形态学和地理分布特征,可以得出群I和群II分别对应荻组和芒组,群Ⅰa和群Ⅰb分别对应荻和南荻;而群Ⅱ内的3个类群分别对应于北方和南方分布的芒,以及五节芒。2)无论在群体水平还是物种水平上,中国的芒属植物都表现出较高水平的遗传多样性,芒组的遗传多样性水平(A=5.25,He=0.569)略高于荻组(A=4.43,He=0.528),荻组和芒组间遗传分化(Fst=0.429)明显高于群组内(Fst=0.138~0.182)。3)物种分布区模拟(species distribution model,SDM)分析显示荻和南荻在末次冰期经历了群体的收缩,之后群体迅速扩张,而芒和五节芒从末次间冰期到现在群体在不断扩张;同时提出五节芒是芒在中国东南部群体生态物种形成的产物。本研究不但能为芒草这一重要能源作物的遗传改良和育种提供有用信息,而且有利于进一步探讨芒属物种的起源和形成过程。
暂无评论