蜘蛛抱蛋属（百合科）二新种

报道了在广西发现的2个百合科蜘蛛抱蛋属Aspidistra新种,即乳突蜘蛛抱蛋A. papillata G. Z. Li和环江蜘蛛抱蛋A. huanjiangensis G. Z. Li&Y. G. Wei。乳突蜘蛛抱蛋与大花蜘蛛抱蛋A. tonkinensis（Gagner. ）F. T. Wang&K. Y. Lang近缘。它们的共同特征是:花单生;花被裂片两侧彼此覆盖;柱头盾状,边缘3裂,上表面具3条辐射状沟缝。不同点是:乳突蜘蛛抱蛋植株较大花蜘蛛抱蛋的粗大;叶柄较粗;叶片椭圆形或长椭圆形;花被阔钟     

蜘蛛抱蛋亚族的花粉形态

本文研究并报道了百合科蜘蛛抱蛋亚族的花粉形态,主要结论如下：1．开口箭属含两种花粉类型即：(1)单槽、椭圆形;(2)无萌发孔、球形。具单槽、椭圆形花粉的种类含单型性核型,花形较小,柱头小而花柱短,雄蕊高于柱头;无萌发孔、球形花粉的种类则为单型性核型,花形较大,柱头常高度膨大,雄蕊常着生在花被筒基部。2．万年青属花粉为椭圆形,具单槽;蜘蛛抱蛋属花粉则为球形,无萌发孔;开口箭属花粉一部分与万年青属相似,另一部分则与蜘蛛抱蛋属雷同。3．蜘蛛抱蛋亚族中最原始的花粉类型为单槽椭圆形,具孔状或网状外壁纹饰。球形,无萌发孔,外壁具皱波状、瘤状或芽孢状纹饰的花粉为派生类型。4．蜘蛛抱蛋亚族种下花粉形状、萌发孔类型和外壁纹饰基本稳定,可作为分种特征。     

云南蜘蛛抱蛋属(天门冬科)一新种——辐射蜘蛛抱蛋

报道了产自云南天门冬科蜘蛛抱蛋属(Aspidistra Ker Gawler)一新种——辐射蜘蛛抱蛋(A.radiata G.W.HuQ.F.Wang)。该种与春秀蜘蛛抱蛋(A.chunxiuensis C.R.LinY.Liu)相近,但该种因叶鞘3~4枚;总花梗较短,长5~9.5 cm,苞片5~7枚;花被裂片较多,常16(偶14或18)深裂,花被筒扁钵形,花被裂片较长,为65~76 mm,基部较宽,为13~16 mm;雄蕊16(偶14或18)枚;柱头上表面中央隆起区从中央向边缘具8(偶7或9)条呈辐射状排列的紫黑色、花瓣状隆起,每个花瓣状隆起的中央具沟槽等特征而与后者不同。辐射蜘蛛抱蛋亦与巨花蜘蛛抱蛋(A.grandiflora Tillich)近缘,但巨花蜘蛛抱蛋的叶片为狭倒卵形,(50×11)cm,基部狭楔形;花被裂片较短,为50~60 mm;柱头上表面中央具5条紫色辐射状的肋而有别于辐射蜘蛛抱蛋。     

中国蜘蛛抱蛋属植物一新记录种——垂花蜘蛛抱蛋

报道了产自云南屏边的中国蜘蛛抱蛋属一新记录种——垂花蜘蛛抱蛋（Aspidistra nutans Aver.&Tillich）。该种是2017年发表的新种,采集于越南西北部地区,原文缺少果实描述,现补充描述该种果的形态特征。本种与辐花蜘蛛抱蛋（A.subrotata Y.Wan&C.C.Huang）在形态上相近,但其叶片中脉和侧脉明显突出,花梗近先端向下弯曲,长0.8~4.5 cm,花下垂,常贴生于地面,花被紫褐色,常平展,柱头纯白色（后者叶脉凹陷,花梗直立,长约5 mm,花斜向上开,花被暗紫色,内面具有小乳突,柱头白色带紫色斑点）而显著有别于后者。     

中国蜘蛛抱蛋属植物一新记录种——垂花蜘蛛抱蛋（英文）

报道了产自云南屏边的中国蜘蛛抱蛋属一新记录种——垂花蜘蛛抱蛋(Aspidistra nutans Aver.Tillich)。该种是2017年发表的新种,采集于越南西北部地区,原文缺少果实描述,现补充描述该种果的形态特征。本种与辐花蜘蛛抱蛋(A. subrotata Y. WanC. C. Huang)在形态上相近,但其叶片中脉和侧脉明显突出,花梗近先端向下弯曲,长0. 8～4. 5 cm,花下垂,常贴生于地面,花被紫褐色,常平展,柱头纯白色(后者叶脉凹陷,花梗直立,长约5 mm,花斜向上开,花被暗紫色,内面具有小乳突,柱头白色带紫色斑点)而显著有别于后者。     

新疆胡颓子属植物花部性状的变异及其分类学价值

新疆胡颓子属植物栽培历史久、变异丰富、种下变异类型多、分类较为困难,因此有必要进一步发掘该属落叶组植物的分类学特征,尤其是对相对保守的繁殖器官的性状进行筛选。该研究以形态较为稳定的繁殖器官为切入点,分析花部性状的变异特点,筛选稳定性状,以期为解决该属的分类难题提供依据。先采用定株采集和同花标记的方法,对比分析了柱头形态、花盘先端有毛无毛、花柱与雄蕊的长短比、花被裂片程度四个性状的稳定性。结果表明:花盘先端有毛无毛、花柱与雄蕊的长短比、花被裂片程度三个性状较稳定,可以作为分类依据;柱头形态在单花中表现稳定,但在单株中出现极大的变异,不具有分类价值;然后采取新疆南、北疆地区的胡颓子属落叶组的尖果沙枣、大果沙枣和沙枣这三种来验证花部性状的稳定性,证明了上述结论的正确性,同时也是对该属分类研究实践的应用。该结果可为胡颓子属的经典分类学和形态学研究以及植物的开发和利用等提供参考依据。     

球隔麻属——荨麻科一新属，兼论荨麻科的柱头

本文描述了分布于中国西藏东南部的荨麻科的一新亚族——球隔麻亚族,一新属—— 球隔麻属及其模式种球隔麻。它被认为是苧麻族较原始的一个类群。其环状柱头及球形药隔 在荨麻科中至今还是首次发现。 本文还论述了荨麻科植物的柱头特征、类型及其分类学意义,并探讨了它们的演化趋势。     

八角属植物分类

根据对18个国家和地区121个标本馆收藏的万余份入角属植物标本研究,结合在国内8个省区野外调查、采集、引种和对生长发育与物侯的观察,本文对世界性八角属植物做了分类学修订。根据花蕾和花被片形态特征的变异,将八角属分为2组：八角组-含9种1亚种,其它蕾卵球形,花被片长圆形、椭圆形、披针形至狭舌状,扁平;八角茴香组-含25种2亚种1变种,其花蕾球形,花被片宽卵形至圆形,下凹。将凹脉组作为八角组的新异名,圆被亚属作为八角茴香组的新异名;指定了红茴香和柬埔寨八角的后选模式。本文还分析了八角属植物的分类学性状,作出有分类检索表,提供有各种植物的地理分布资料,列举出查阅的主要标本,并对各分类单元均作了分类学注释。     

蜘蛛抱蛋属中甾体皂甙的分布

在文献资料和实验研究的基础上,本文总结了甾体皂甙在蜘蛛抱蛋属植物中的分布。发现单羟基的薯蓣皂甙元的配糖体一蜘蛛抱蛋皂甙(薯蓣皂甙元-3-O[β-D-葡萄吡喃糖基(1→2)]-[β-D-木吡喃糖基(1→3)]-β-D-葡萄吡哺糖基(1→4)-β-D-半乳吡哺糖甙),广泛存在于所研究过的这些植物中,而且是大部植物根茎的主要皂甙。它是蜘蛛抱蛋属植物的特征化学成分,表明该属是一个自然类群,甾体皂甙对它是有分类学意义的。     

蜘蛛抱蛋属中甾体皂甙的分布

在文献资料和实验研究的基础上,本文总结了甾体皂甙在蜘蛛抱蛋属植物中的分布。发现单羟基的薯蓣皂甙元的配糖体—蜘蛛抱蛋皂甙（ 薯蓣皂甙元＿３＿Ｏ［βＤ葡萄吡喃糖基（１ →２）］［βＤ木吡喃糖基（１ →３）］βＤ葡萄吡喃糖基（１ →４）βＤ半乳吡喃糖甙） ,广泛存在于所研究过的这些植物中,而且是大部植物根茎的主要皂甙。它是蜘蛛抱蛋属植物的特征化学成分,表明该属是一个自然类群,甾体皂甙对它是有分类学意义的     

More is better: the uses of developmental genetic data to reconstruct perianth evolution

The origin and evolution of the perianth remains enigmatic. While it seems likely that an undifferentiated perianth consisting of tepals arose early in angiosperm evolution, it is unclear when and how differentiated perianths consisting of distinct organs, such as petals and sepals, arose. Phylogenetic reconstructions of ancestral perianth states across angiosperms have traditionally relied on morphological data from extant species, but these analyses often produce equivocal results. Here we describe the use of developmental genetic data as an additional strategy to infer the ancestral perianth character state for different angiosperm clades. By assessing functional data in combination with expression data in a maximum likelihood framework, we provide a novel approach for investigating the evolutionary history of the perianth. Results of this analysis provide new insights into perianth evolution and provide a proof of concept for using this strategy to explore the incorporation of developmental genetic data in character state reconstructions. As the assumptions outlined here are tested and more genetic data are generated, we hope that ancestral state reconstructions based on multiple lines of evidence will converge.     

MADS about the evolution of orchid flowers

Orchids have unique flowers involving three types of perianth organs: outer tepals, lateral inner tepals, and a lip. Expression studies indicate that the identity of these organs is specified by the combinatorial interaction of four different DEFICIENS-like MADS-box genes. We suggest that clarifying the evolution of these genes provides a rational framework for reconstructing the enigmatic origin and unique diversification of the orchid flower. For example, two rounds of gene duplications during early orchid evolution might have generated the genes that were probably recruited to distinguish the different types of perianth organs. This hypothesis suggests intriguing, experimentally testable mechanisms by which gene duplications followed by sub- and neo-functionalization events might have contributed to the evolutionary origin of morphological novelties in orchids - and well beyond.     

植物进化发育生物学的形成与研究进展

植物进化发育生物学是最近十几年来才兴起的一门学科, 它是进化发育生物学的主要分支之一。进化发育生物学的产生经历了进化生物学与胚胎学、遗传学和发育生物学的三次大的综合, 其历史可追溯到19世纪初冯.贝尔所创立的比较胚胎学。相关研究曾沉寂了近一个世纪, 直到20世纪80年代早期, 动物中homeobox基因被发现, 90年代初花发育的 ABC模型被提出, 加之对发育相关基因研究的不断深入, 才使基因型与表型联系了起来, 进而促进了进化发育生物学的飞速发展。目前进化发育生物学已成为21世纪生命科学领域的研究热点之一。本文详细阐述了进化发育生物学产生和发展的历程, 综述了最近十几年来植物进化发育生物学的主要研究进展。文中重点介绍了与植物发育密切相关的MADS-box基因在植物各大类群中的研究现状, 讨论了植物进化发育生物学领域的研究成果对花被演化、花对称性以及叶的进化等重要问题的启示。     

植物进化发育生物学的形成与研究进展

植物进化发育生物学是最近十几年来才兴起的一门学科,它是进化发育生物学的主要分支之一。进化发育生物学的产生经历了进化生物学与胚胎学、遗传学和发育生物学的三次大的综合,其历史可追溯到19世纪初冯.贝尔所创立的比较胚胎学。相关研究曾沉寂了近一个世纪,直到20世纪80年代早期,动物中homeobox基因被发现,90年代初花发育的ABC模型被提出,加之对发育相关基因研究的不断深入,才使基因型与表型联系了起来,进而促进了进化发育生物学的飞速发展。目前进化发育生物学已成为21世纪生命科学领域的研究热点之一。本文详细阐述了进化发育生物学产生和发展的历程,综述了最近十几年来植物进化发育生物学的主要研究进展。文中重点介绍了与植物发育密切相关的MADS-box基因在植物各大类群中的研究现状,讨论了植物进化发育生物学领域的研究成果对花被演化、花对称性以及叶的进化等重要问题的启示。     

Giant Flowers of Southern Magnolia Are Hydrated by the Xylem

Flowering depends upon long-distance transport to supply water for reproductive mechanisms to function. Previous physiological studies suggested that flowers operated uncoupled from stem xylem transport and received water primarily from the phloem. We demonstrate that the water balance of Southern magnolia (Magnolia grandiflora) flowers is regulated in a manner opposite from that of previously examined flowers. We show that flowers of Southern magnolia rely upon relatively efficient xylem hydraulic transport to support high water demand during anthesis. We measured rapid rates of perianth transpiration ranging from twice to 100 times greater than previous studies. We found that relatively efficient xylem pathways existed between the xylem and flower. Perianth hydraulic conductance and the amount of xylem to transpirational surface area ratios of flowers were both approximately one-third those measured for leafy shoots. Furthermore, we observed that perianth tissues underwent significant diurnal depressions in water status during transpiring conditions. Decreases in water potential observed between flowers and vegetative tissues were consistent with water moving from the stem xylem into the flower during anthesis. Xylem hydraulic coupling of flowers to the stem was supported by experiments showing that transpiring flowers were unaffected by bark girdling. With Southern magnolia being a member of a nearly basal evolutionary lineage, our results suggest that flower water balance represents an important functional dimension that influenced early flower evolution.     

PERIANTH DEVELOPMENT OF POTAMOGETON RICHARDSONII

Interpretation of the Potamogeton flower is complicated by the attachment of the “perianth segment” to the stamen connective. Developmental studies show that the perianth segments are not outgrowths of the stamen connectives. They are initiated on the floral apex acropetally before the (superposed) primordia of the stamens. After the inception of the stamen primordia, growth occurs in the regions between the primordia of each perianth segment and stamen. Thereby the bases of the developing perianth segment and stamen become united, and in the adult flower eventually the perianth segment is inserted on the connective of the stamen. The primordium of the perianth segment develops from the 2 outer layers (tunica) of the floral apex, in contrast to the stamen primordium which originates from the 3 outer layers. The vascular bundles for each perianth segment–stamen region develop acropetally from 1 common bundle which bifurcates into 1 bundle for the perianth segment and 1 for the stamen. The bundle leading into the perianth segment branches in a more or less dichotomous manner. The veins form none or only 1 or 2 anastomoses at the base of the lamina, whereas the vein endings remain free. The interpretation of the perianth segments is discussed in terms of the classical and the gonophyll theory. Since both theories rest on an ambiguous methodological basis, interpretation is postponed until a new approach to comparative morphology has been worked out and until the floral development of other Helobiales has been studied.     

Evolutionary Trends in the Flowers of Asteridae: Is Polyandry an Alternative to Zygomorphy?

Background and Aims

Floral symmetry presents two main states in angiosperms, actinomorphy (polysymmetry or radial symmetry) and zygomorphy (monosymmetry or bilateral symmetry). Transitions from actinomorphy to zygomorphy have occurred repeatedly among flowering plants, possibly in coadaptation with specialized pollinators. In this paper, the rules controlling the evolution of floral symmetry were investigated to determine in which architectural context zygomorphy can evolve.

Methods

Floral traits potentially associated with perianth symmetry shifts in Asteridae, one of the major clades of the core eudicots, were selected: namely the perianth merism, the presence and number of spurs, and the androecium organ number. The evolution of these characters was optimized on a composite tree. Correlations between symmetry and the other morphological traits were then examined using a phylogenetic comparative method.

Key Results

The analyses reveal that the evolution of floral symmetry in Asteridae is conditioned by both androecium organ number and perianth merism and that zygomorphy is a prerequisite to the emergence of spurs.

Conclusions

The statistically significant correlation between perianth zygomorphy and oligandry suggests that the evolution of floral symmetry could be canalized by developmental or spatial constraint. Interestingly, the evolution of polyandry in an actinomorphic context appears as an alternative evolutionary pathway to zygomorphy in Asteridae. These results may be interpreted either in terms of plant–pollinator adaptation or in terms of developmental or physical constraints. The results are discussed in relation to current knowledge about the molecular bases underlying floral symmetry.Key words: Floral symmetry, architectural constraints, Asteridae, comparative analysis, composite tree, correlated evolution, evolutionary scenario     

The morphology and relationships of the Sphaerosepalaceae (Malvales)

The comparative vegetative and reproductive morphology and anatomy of the Malagasy endemic family Sphaerosepalaceae is examined in light of two current competing hypotheses of relationship from recent molecular studies. Sphaerosepalaceae are similar to Thymelaeaceae on the basis of leaf architecture, calyx vasculature and in having endostomal micropyles. Comparisons with Tepuianthus and Thymelaeaceae subfamily Octolepidoideae are drawn on the basis of seed structure, indument type, perianth structure and pollen. Resin-filled, sclerenchymatous idioblasts, floral (positional) monosymmetry, a single series of stamen trunk bundles and a well-developed bixoid chalaza in the seed of Dialyceras parvifolium link Sphaerosepalaceae with its other putative sister group: a clade containing Bixaceae, Cochlospermaceae and Diegodendraceae. Synapomorphies of Sphaerosepalaceae include: fused, intrapetiolar stipules, embryo structure, pollen with endoapertures encompassing the ectoapertures and a tetramerous perianth. The extremely well-developed apical septum in the eusyncarpous gynoecium of Rhopalocarpus suggests that the gynoterminal style present in this genus has been secondarily derived from an ancestor with a fully syncarpous, basistylous gynoecium, as in Dialyceras . The morphological and evolutionary nature of basistylous and apically septate gynoecia is discussed. A rosette arrangement of ovules in each carpel coccus of D. coriaceum expands the bauplan concept of Sphaerosepalaceae and is probably unique among angiosperms as a whole.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 144 , 1–40.     

Evolution of herkogamy and gynodioecy in Moroccan species ofRomulea (Iridaceae)

Herkogamy and gynodioecy were studied in the Moroccan species ofRomulea. Several types of herkogamy are shown to occur in the different species, with each type corresponding to a characteristic perianth size. The degree of differentiation between female and hermaphrodite morphs varies among the different gynodioecious species. Herkogamy is considered to have evolved prior to the development of the gynodioecious condition. An evolutionary interpretation is proposed based on the degree of herkogamy and of gynodioecy in the different species.     

蝴蝶兰花发育的分子生物学研究进展

蝴蝶兰花非常独特且高度进化,如萼片瓣化、瓣片特化为唇瓣、雌雄蕊合生成合蕊柱及子房发育须由授粉启动等,是单子叶植物花发育研究的理想材料。近年来蝴蝶兰花发育分子生物学取得了重要进展。该文就近年来国内外有关蝴蝶兰开花转换及花器官发育相关基因研究以及B类基因与兰花花被的进化发育关系方面的研究进展进行综述。研究表明:MADS基因在蝴蝶兰开花转换及花器官发育过程中起重要作用,推测其中的DEF(DE-FICIENS)-like基因早期经过2轮复制,形成了4类不同的DEF-like基因,进而决定兰花花被属性。蝴蝶兰花发育分子生物学的深入研究,将极大地利于通过基因工程手段提高蝴蝶兰花品质如花色改良及花期调控等,推动分子育种进程。