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1.
The Tofieldieae consist of Narlhecium, Nietneria, Pleea , and Tofieldia. Although the three carpels of the pistil are generally coherent, their bases are separate for a short distance in some species of Tofieldia and in Pleea , where a septal nectary seems to be differentiated. These two genera are also alike in the extension of the chalaza as a filiform hook. The sutures are open at flowering only in some species of Tofieldia. Nietneria is distinguished by its inferior ovary and the alternate structure of the pistil. No raphide idioblasts were found in the carpels of any species. 相似文献
2.
The young pistils in the melanthioid tribes, Hewardieae, Petrosavieae and Tricyrteae, are uniformly tricarpellate and syncarpous. They lack raphide idioblasts. All are multiovulate, with bitegmic ovules. The Petrosavieae are marked by the presence of septal glands and incomplete syncarpy. Tepals and stamens adhere to the ovary in the Hewardieae and the Petrosavieae but not in the Tricyrteae. Two vascular bundles occur in the stamens of the Hewartlieae and Tricyrtis latifolia. Ventral bundles in the upper part of the ovary of the Hewardieae are continuous with compound septal bundles and placental bundles in the lower part. Putative ventral bundles occur in the alternate position in the Tricyrteae and putative placental bundles in the opposite. position in the Petrosavieae. The dichtomously branched stigma in each carpel of the Tricyrteae is supplied by a bifurcated dorsal bundle. 相似文献
3.
Most Helonieae have only slight septal indentations between the three carpels: in Xerophyllum deep septal clefts extend centripetally and completely enclosed, narrow septal pockets occur in Metanarthecium . Other unique generic features are found: tepallary-staminal nectarial glands in Heloniopsis , zygomorphy in Chionographis , and dioecism in Chamaelirium . The carpels are biovulate in Chionographis; there are two to several ovules per carpel in Xerophyllum; 8–12 ovules occur in the carpel of Chamaelirium; and numerous bitegmic ovules are borne in many longitudinal rows on enlarged placentae in Helonias, Heloniopsis, Metanarthecium , and Ypsilandra . Except for Metanarthecium , this last-named group of genera displays a near ring composed of 'accessory' placental bundles and a compound septal bundle (with normally oriented xylem and phloem) in cross-section at the inner edge of each septum. Ventral bundles occur in the other four genera. 相似文献
4.
CLARENCE STERLING F.L.S. 《Botanical journal of the Linnean Society. Linnean Society of London》1982,84(1):57-77
The genera of the Veratreae, a tribe of the Melanthioideae, have many features in common: there are usually many ovules, except for Amianthium (with 2 4), arranged in 2 -4 longitudinal placental rows per carpel; all are bitegmic, basipetal, and campylotropous. Of 37 species examined, only 2 have open sutures at the lowermost level of ovular insertion, but 13 species have holes in the centre of the pistil. These holes may represent possible stages in the evolutionary closure of previously open sutures. Most flowers were epigynous, only 11 being hypogynous-perigynous. The tribe as a whole is marked by the presence of 3 composite (heterologous) vascular bundles, composed of joined staminal and tepallary bundles alone and 3 composite bundles, as above, fused to a dorsal bundle. The bundles were united below the locular base in all genera except Schoenocaulon and Toxicoscordion. Two major kinds of central cylinder arrangement occurred at the level of the lowermost ovular insertion: either 6 inverted ventral bundles or 6 simple septal bundles, with normally arranged (or sometimes inverted) xylem and phloem centrifugally located and 6 simple placental bundles, with inverted xylem and phloem, at the centripetal end of the septum. Generally each septal bundle united with its nearest adjoining placental bundle about the mid-locular level. 相似文献
5.
CLARENCE STERLING 《Botanical journal of the Linnean Society. Linnean Society of London》1973,66(1):75-82
The two genera of Buxbaum's tribe Wurmbaeae, Anguillaria and Wurmbea , have multiovulate carpels. There are deep septal indentations between the carpels of Anguillaria , but the wings of adjoining carpels are fused to solid septa in most species of Wurmbea. In Anguillaria the carpels have open sutures or prominent commissural markings; in Wurmbea the carpels generally lack these characteristics, and some species have a vascularized, columella-like axis in the centre of the pistil. In both genera there are a dorsal bundle, lateral bundles, and two placental bundles in each carpel. At the inner edge of the septum there are one or two septal bundles in Anguillaria and one or none in Wurmbea. The ovules are monotegmic, the integument and funiculus being partly fused in Anguillaria and mostly fused in Wurmbea. An obturator is present in Anguillaria but absent from most species of Wurmbea. 相似文献
6.
CLARENCE STERLING F.L.S 《Botanical journal of the Linnean Society. Linnean Society of London》1974,68(4):283-290
The pistil in the flowers of the Iphigenieae (Camptorrhiza, Iphigenia, Omithoglossum) is usually tricarpellate. The carpels are coherent generally, with closed sutures and seemingly bitegmic ovules. Camptorrhiza differs from the others in having a single compound style. The pistils of most species of these genera have a common vascular structure: three dorsal bundles which run into the style(s), a number of lateral bundles, six placental bundles, and up to three compound septal bundles. The latter nine bundles usually differentiate from a central vascular plexus above the base of the locules. There may be fewer than three septal bundles in some specieS. When present, the septal bundles usually die out in the ovuliferous region, but in some cases they persist to the apex of the locules. 相似文献
7.
CLARENCE STERLING 《Botanical journal of the Linnean Society. Linnean Society of London》1972,65(2):163-171
The structure of the carpel has been studied in flowers of the Neodregeae ( Dipidax and Neodregea ). Except in D. triquetra , which is syncarpous, the carpels are united below and free above. A dorsal bundle, two or more lateral bundles, and two placental bundles supply each multiovulate carpel. The six placental bundles of the tricarpellate pistil are united by twos in the lower part of the pistil, forming three opposite compound placental bundles in most species of Dipidax and three alternate bundles in D. triquetra and Neodregea : In the latter, an additional septal bundle continues upward as a branch from the compound placental bundle. Sutural openings are usually short and restricted to the top of the locule. All the Neodregeae have monotegmic ovules. 相似文献
8.
CLARENCE STERLING 《Botanical journal of the Linnean Society. Linnean Society of London》1975,70(4):341-349
The pistils of the Glorioseae (Gloriosa, Littonia, Sandersonia) are generally tricarpellate and alike. Virtually all have closed sutures at flowering; they have many ovules, some of which are barely bitegmic, with inner integuments often nearly fused with nucellar remnants; and there is usually but one compound septal bundle in the inner edge of a septum. In two species of Littonia , the compound septal bundle divided to form two simple septal bundles; but in many other plants it remained undivided, and in some it died out, still undivided, below the locular apex. Most of the placental and septal bundles are vascularized in large part by three alternate (compound septal) bundles at the base of the locules and sometimes by branches from the lateral bundles. Three large (compound) placental bundles are formed just below the lowermost ovular insertion, and each then divides in two to furnish ovular branches along their ascent. Occasional auxiliary placental bundles lie between the septal bundle and the placental bundles in the septum (Gloriosa, Sandersonia). 相似文献
9.
CLARENCE STERLING 《Botanical journal of the Linnean Society. Linnean Society of London》1973,66(3):213-221
The pistil of Colchicum is syncarpous, the carpels having open sutures or well-marked commissures and many bitegmic ovules of variable orientation. Although the vascularization of the carpel is also variable, there are usually three dorsal bundles and three alternate, septal bundles at the base of the pistil, with occasionally some placental bundles at that level. More often the placental bundles, differentiating basipetally, appear to establish connections with the septal bundles higher up, at the lowermost ovular insertion level. The septal bundles divide in two more frequently in pistils in which the carpellary suture is open than in those in which it is closed. 相似文献
10.
CLARENCE STERLING 《Botanical journal of the Linnean Society. Linnean Society of London》1973,67(2):149-156
The pistil of Androcymbium closely resembles that of Colchicum : it is tricarpellate usually, syncarpous and multiovulate, and the carpels of most species have open sutures and bitegmic ovules. The only species with closed carpellary sutures, A. dregei has monotegmic ovules. There are always three dorsal bundles and three compound septal bundles, which latter may bifurcate into simple septal bundles. Six placental bundles (two per carpel) are differentiated, either separately from the compound septal bundles or as lateral branches of them. A statistical evaluation of 47 species (6 genera) of the hemisyncarpous Wurmbaeoideae shows a significant tendency for bitegmic ovules and two simple septal bundles per septum to be associated with open sutures and for monotegmic ovules and no septal bundles to be associated with closed sutures. 相似文献
11.
CLARENCE STERLING 《Botanical journal of the Linnean Society. Linnean Society of London》1974,68(2):115-125
The pistils in Baeometra, Burchardia and Walleria ate tricarpellate, and their ovules are mostly bitegmic. Baeometra has free styles and deep septal invaginations between the carpels. Its pistil is innervated by three dorsal bundles, three compound septal bundles (each of which may divide into two simple septal bundles above), six placental bundles, and six adjoining auxiliary placental bundles. The pistil of Burchardia resembles that of Baeometra , except that there are six simple septal bundles throughout and no auxiliary placental bundles. In Walleria the wings of adjoining carpels are completely fused (except for rare septal glands); there is a single compound style; additional vascular tissue is present in the central axis of the pistil up to the lowermost ovules; the carpels are fused with the floral cup above the base of the locules; and raphide idioblasts are present. Walleria has six "ventral" bundles, each of which appears to be the fusion product of a placental bundle with a simple septal bundle. Tribal affinities of these genera are discussed. 相似文献
12.
CLARENCE STERLING 《Botanical journal of the Linnean Society. Linnean Society of London》1977,74(1):63-69
Tepallary and staminal vascularization in a random sample of the Wurmbaeoideae was eomprised of three vascular bundles per tepal and one per stamen, as in the Rosaceae. The structural similarity of the vascularization of the carpel of the Wurmbaeoideae with that of the Rosaceae is mentioned with the tentative implication of a common ancestry. 相似文献
13.
Pollen grains of 26 species of the genus Gagea distributed in Iran were examined by light and scanning electron microscopy. Detailed pollen morphological characteristics are given for these species. Among the studied species, the newly described G. iranica together with G. olgae and G. graminifolia possess the smallest pollen grains, and the widely distributed G. lutea the largest ones. Our studies show that the sculpturing of exine provides valuable characters for separating the species, sometimes even for closely related ones, and delimitation of natural groups within the genus. The exine of the genus Gagea is in most cases perforated upon tectum or rarely tectate-columellate. The muri are solid or structured, compound, simpli-, dupli- or pluricolumellate. It seems that the structure of muri is very important in recognizing natural groups within the genus. Tectal perforations vary from <0.2 to 2.0 μm in diameter among the studied species. Regarding sculpturing of the exine in proximal face, four basic types of pollen grains can be distinguished: reticulate, microreticulate, foveolate and perforate. Within the reticulate type there is sufficient variation in exine structure at distal face to describe three subtypes: reticulate, microreticulate and perforate. A diagnostic key is given for all studied taxa based on palynomorphological characters. For a limited number of populations of selected Iranian species of Gagea, further aspects of pollen biology were studied. It seems that populations with ploidy levels other than diploidy, show a low percentage of pollen fertility. Moreover, the rate of pollen fertility is correlated with the manner of the reproduction in certain species. 相似文献
14.
15.
LOUIS-PHILIPPE RONSE DECRAENE J. R. AKEROYD F.L.S. 《Botanical journal of the Linnean Society. Linnean Society of London》1988,98(4):321-371
In order to investigate the taxonomic value of a number of characters in the elucidation of relationships within the collective genus Polygonum L., and segregate genera Atraphaxis L., Calligonum L., Pteropyrum Jaub. & Spach., Oxygonum Burch., Fagopyrum Mill., Harpagocarpus Hutch. & Dandy and Polygonella Michx., 83 species of the tribe Polygoneae emend. Jaretzky were studied. The following floral characters were examined: stamen number, insertion and external morphology; structure and morphology of the floral nectaries; vasculature and surface morphology of the tepals.
Problems in floral morphology in Polygonaceae are discussed, together with relationships within the Family. The tribal division proposed by Haraldson (1978) is supported, but a new and different delimitation of genera is proposed. The present data support a division of Polygonum L. sensu lato and its related taxa into two tribes: Polygoneae (containing Polygonum L. sensu stricto, Fallopia Adans., Oxygonum Burch., Pteropyrum Jaub. & Sparh., Atraphaxis L. and Calligonum L.), and Persicarieae (containing Fagopyrum Mill., Harpagocarpus Hutch. & Dandy, Persicaria Mill. and Koenigia L.). The genus Reynoutria Houtt. is included as a section of Fallopia Adans.; Bislorta Mill., Aconogonon Reichenb. and Tovara Adans. are included within Persicaria Mill.
A number of new combinations are proposed in Persicaria and Fallopia . 相似文献
Problems in floral morphology in Polygonaceae are discussed, together with relationships within the Family. The tribal division proposed by Haraldson (1978) is supported, but a new and different delimitation of genera is proposed. The present data support a division of Polygonum L. sensu lato and its related taxa into two tribes: Polygoneae (containing Polygonum L. sensu stricto, Fallopia Adans., Oxygonum Burch., Pteropyrum Jaub. & Sparh., Atraphaxis L. and Calligonum L.), and Persicarieae (containing Fagopyrum Mill., Harpagocarpus Hutch. & Dandy, Persicaria Mill. and Koenigia L.). The genus Reynoutria Houtt. is included as a section of Fallopia Adans.; Bislorta Mill., Aconogonon Reichenb. and Tovara Adans. are included within Persicaria Mill.
A number of new combinations are proposed in Persicaria and Fallopia . 相似文献
16.
植物性系统进化过程中很少有植物通过雌性败育的方式实现性系统由联合走向分离,然而雄花在百合科植物中大量存在,引起了研究者的关注。本研究利用百合科豹子花属植物的腊叶标本,获取它们的花性别表型、花大小、株高以及分布海拔等信息探讨豹子花属植物的性表达样式,并对样本量较多的开瓣豹子花、云南豹子花、多斑豹子花和豹子花四个种的性表达及其与个体大小的关系进行分析。研究结果表明:1)六种豹子花属植物标本中都有雄花存在;根据雄性花和两性花的不同组合,形成雄性个体、两性花个体,和雄花两性花同株个体三种植株类型;2)个体大小(株高)和分布海拔之间不存在相关关系,和植株性别类型相关,即雄性个体一般显著小于具有雌性功能的两性花个体和雄花两性花同株个体;3)个体大小与花大小、每个个体开花总数和雌花数量成显著的正相关关系,而与每个个体的雄花数量无显著的相关关系。本研究更正了一直以来对豹子花属植物性系统的错误认识,首次报道雄花在豹子花属植物中普遍存在,并指出雄花和雄性个体的出现是大小依赖性分配的结果。同时,以研究实例证明了利用腊叶标本开展植物性系统多样性的可行性。 相似文献
17.
18.
Observations on the vascular floral anatomy, carpel morphology and floral biology ofHeloniopsis orientalis are presented. The lower flowering pedicel has six large bundles which lack an enclosing sclerenchymatous sheath. At mid-pedicel,
branch bundles originate via radial divisions from each of these bundles. Subsequently, there is a vascular ring of 12 bundles
below the receptacle. The six smaller bundles which are derived from alternate pedicel bundles eventually establish all of
the ventral gynoecium supply. The six larger bundles supply the tepals, stamens and dorsal gynoecial vasculature. The simple
dorsals do not branch or fuse in their vertical ascent.
The ventral and placental supplies are far more complex. Fusion occurs between paired sets of the six smaller pedicel bundles
along the septal radii and results in a submarginal laminal ventral network. An independent ventral plexus is formed in each
septum and from each plexus two septal axials, of which the innermost has a reversed xylem-phloem disposition, and four placental
bundles are derived. Two placental bundles are associated with each septal axial. Basally the septa are fused centrally, but
are freed at mid-gymoecial height.
The broadly tri-lobed, tri-carpellate gynoecium is depressed terminally where the erect, hollow style with its capitate stigma
is attached. Dorsal grooves are present: the fruit is loculicidally dehiscent. There are no septal glands due to complete
lateral fusion of the septal wings. Basally each of the six equal tepals has a saccate nectary. The similarity in vascular
anatomy and carpel morphology of the AsianHeloniopsis and eastern North American endemic,Helonias bullata, justifies their position in the same tribe.
Research and publication supported in part by the M. Graham Netting Research Fund through a grant from the Cordelia Scaife
May Charitable Trust, the U. S.—Japan Cooperative Science Program Grant GF-41367, the Japan Society for the Promotion of Science,
and Grant-in-Aid No. 934053 from the Ministry of Education, Japan. 相似文献
19.
The primary vascular elements originate in the procambia of the single carpel and three stamens of the floret independently and in isolation from the vascular system of the spikelet. The initiation of protophloem elements is earlier in the stamens than in the carpel. The median strand of the carpel differentiates before the two lateral strands. The protoxylem elements are initiated after the protophloem elements are welt differentiated.
The differentiation of both protophloem and protoxylem elements is bidirectional in the stamens and in the three strands of the carpel, whereas their differentiation is acropetal in the funicular strand of the carpel. 相似文献
The differentiation of both protophloem and protoxylem elements is bidirectional in the stamens and in the three strands of the carpel, whereas their differentiation is acropetal in the funicular strand of the carpel. 相似文献
20.
对子午岭产百合科黄精属大苞黄精(P.megaphyllum)、玉竹(P.odoratum),百合属的细叶百合(L.pumilum),葱属的糙葶韭(A.anisopodium)4种植物进行了染色体研究。其染色体数目和核型分别为:玉竹2n(2x)=20=12m(2SAT)+8sm,核型为2B型;大苞黄精2n(2x)=22=4m+12sm+6st,核型为3B型;细叶百合2n(2x)=24=4m+10st 相似文献