Morphological architecture of Actinocephalus (Koern.) Sano (Eriocaulaceae-Poales)

Actinocephalus exhibits perhaps more diversity in habit than any other genus of Eriocaulaceae. This variation is largely a result of differences in the arrangement of the paraclades. Based on the analysis of stem architecture of all 25 species of Actinocephalus, the following patterns were established: (1) leaf rosette, with no elongated axis, instead the axillary paraclades originating directly from the short aerial stem, (2) rosette axis continuing into an elongated axis with spirally arranged paraclades, (3) an elongated axis originating from a rhizome, with ramified paraclades, and (4) an elongated axis originating from a short aerial stem, with paraclades arranged in a subwhorl. The elongated axis exhibits indeterminate growth only in pattern 4. Patterns 3 and 4 are found exclusively in Actinocephalus; pattern 1 occurs in many other genera of Eriocaulaceae, while pattern 2 is also found in Syngonanthus and Paepalanthus. Anatomically, each stem structure (i.e., paraclade, elongated axis, short aerial stem, rhizome) is thickened in a distinctive way and this can be used to distinguish them. Specifically, elongated axes and paraclades lack thickening, thickening of short aerial stems results from the primary thickening meristem and/or the secondary thickening meristem. Thickening of rhizomes results from the activity of the primary thickening meristem.     

Morphology and development of the reproductive shoots of Lilaea scilloides (Poir.) Hauman (Alismatidae)

Shoots of adult plants of Lilaea scilloides have a sympodial form. Each unit of the sympodium bears a single sheathing prophyll (which is the only kind of foliage leaf produced in the adult) and terminates in an inflorescence. The prophyll subtends the next unit of the sympodium. A further accessory bud can form in association with each unit. This bud repeats the pattern of the main sympodium, giving the plant a tufted habit. Five different kinds of flower can be identified in the inflorescence: a unisexual male flower with a single perianth member and adnate stamen; a bisexual flower, with a single perianth member and adnate stamen, and a single carpel with an anatropous bitegmic ovule; a unisexual female flower with a single perianth member and carpel; a unisexual female flower comprising only a single carpel; and a female flower comprising only a single carpel with a very long filamentous style. The first four kinds occur in the upper part of the inflorescence which is normally elevated on a scape, while the last kind is restricted to the base of the inflorescence. In the position of the basal flowers several variations have been observed in cultivated material. These include branching associated with the basal flowers, which results in the development of additional basal flowers or inflorescences, and even total replacement of a basal flower by an inflorescence or a branching structure bearing flowers. A review of past literature includes a clarification of some persistent errors which have confused the taxonomic position of the plant and the morphological interpretation of the reproductive appendages.     

雌先熟植物茄参（茄科）的繁育系统

对分布于云南西北部的茄参（Mandragoraca caulescens）的繁育系统进行了研究。茄参的花期为5月底到6月初,单花持续时间为（9．9±2．8）d,其性表达方式为雌性先熟。有三种昆虫拜访茄参的花,白背熊蜂蜂王是最有效的传粉昆虫,但其访花频率很低;苍蝇和蚂蚁的访花频率较高,但苍蝇传粉效率十分有限;蚂蚁是窃蜜者。授粉实验证明茄参具有部分自交亲和能力,但由于雌性先熟,不具备主动自交能力。人工添加异交花粉显著提高了结实率和结籽数,证明茄参存在花粉限制。茄科的大部分植物是严格自交不亲和的,但茄参族的茄参是自交部分亲和,这和茄科天仙子族的部分成员类似。我们认为这两个独立起源于新世界向欧亚大陆扩散事件的族,各自从自交不亲和向自交亲和转变可能与高山地区恶劣的自然条件有关,这种繁育系统的进化模式是否具有普遍性值得进一步研究。     

Development of Leaf Forms in Ipomoea reptans (Linn.) Poir

Development of leaves of two chromosomal biotypes of Ipomoeareptans, one with broad leaves and the other with narrow leaves,was studied. Early development of the ‘narrow’ typeinvolves a rapid multiplication of cells without expansion.This phase is followed by cell enlargement with a negligibleamount of multiplication. In the ‘broad’ type onthe other hand, multiplication and enlargement are simultaneousand proceed slowly, but steadily. The lamina shape of both thebiotypes is primarily related to a difference of cell multiplicationrate in the basal, median and apical parts. Some gradient influencingcell multiplication probably exists from the base to the tipof lamina, the optimum point being in the middle. Maturationand enlargement of cells is basipetal and continuous. The wavynature of the leaf margin is related to a very accurate geometricaladjustment of cell number variation in depressions and mounds,which may be controlled by a product of the lateral veins.     

Self-pollination of Asarum caulescens Maxim. (Aristolochiaceae) in Japan

Abstract Observations in two populations of Asarum caulescens belonging to sect. Asarum indicate that inbreeding predominates becuase (1) no effective pollinator was observed, (2) bagged flowers set fruits with well-swollen seeds, and (3) the behaviour of filaments, changing from recurved to straight posture, results in direct deposition of pollen grains on the stigmas. This result agrees with reports on three other species of sect. Asarum in Europe and North America. We suggest that species of sect. Asarum diverged from an autogamous ancestor.     

Embryology and disorders of sexual development

Recent consensus is that individuals with atypical male or female phenotype are to be considered to have a "disorder of sexual development." The goal is to eliminate previous terminology that included the terms intersex, hermaphrodite, or pseudohermaphrodite. However, the teaching of embryology, and particularly teaching about the development of the reproductive system, still has not made the change to the new terminology. If those who teach embryology to health-care professionals remain unaware of the controversies associated with the old terminology and continue to use it, they will perpetuate a nomenclature that can be destructive. Any terminology must be used carefully to avoid dehumanizing the individual to a disease or a medical state. We should be able to state clearly the variations in morphology that exist, attend to the immediate health of the individual, and avoid any attempt to stigmatize gender-atypical individuals.     

Embryology of Calenduleae (Compositae)

Microsporangial conditions, macrosporogenesis, embryo sac development and in some species endosperm formation have been studied in 5 species of Dimorphotheca Vaill. ex Mnch, 2 species of Castalis Cass., 16 species of Osteospermum L., 6 species of Calendula L., 1 species of Gibbaria Cass., and 1 species of Chrysanthemoides Tourn. ex Fabr.
The microsporangial wall consists of four different layers of cells. Miocrospore formation is simultaneous. The tetrads are mostly arranged in tetrahedrals. A tapetal periplasmodium develops.
The archespore of the macrosporangium is in most cases 1-celled, sometimes 2-or many-celled. The meiosis gives rise to a linear tetrad. Usually the chalazal macro-spore develops. The embryo sac development is monosporic of the Polygonum type. In a few cases in Dimorphotheca venusta T. Norl. a tetrasporic embryo sac development was observed besides the Polygonum type. Castalis tragus (Ait.) T. Norl. may have a bisporic embryo sac development in addition to the Polygonum type. All the Calendula species develop synergid haustoria. Antipode haustoria occur in Osteospermum sinuatum (DC.) T. Norl. and Chrysanthemoides monilifera (L.) T. Norl. Chalazally situated extra embryo sacs below the ordinary one in Dimorphotheca sinuata DC, D. venusta , and Castalis nudicaulis var. graminifolia (L.) T. Norl. are regarded to be aposporic. Six species have more than three antipodes per embryo sac. The antipodes occasionally become 2-or 4-nucleate.     

Embryology in Norway spruce (Picea abies). An analysis of the composition of seed storage proteins and deposition of storage reserves during seed development and somatic embryogenesis

Seed cones were collected from open-pollinated trees of Norway spruce ( Picea abies ) in a seed orchard from pollination until maturation of the seeds. Immature embryos were isolated for embryogenic tissue cultures that were maintained either on solidified medium or as liquid cultures. By transferring young somatic embryos to medium containing 90 m M sucrose and 7. 6 μ M ABA growth continued to mature embryos that accumulated storage reserves in both the hypocotyl-shoot axis and the cotyledons. Both zygotic and somatic embryos at different developmental stages were processed for microscopy as were the megagametophytes. Total protein was extracted from the seed material at intervals during development and analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. These analyses revealed that storage protein started to accumulate in the megagametophytes at the time when embryos were growing into the gametophytic tissue, while it occurred a few weeks later in the embryos at rapid embryo growth and organ differentiation. Lipid bodies also became abundant in the mature plant material. Although plastids with prominent starch grains were very frequent in both megagametophytes and embryos during development they were not observed in the desiccated tissues. Zygotic and somatic embryos displayed a similar developmental pattern.
By sequential salt-extraction and dilution two fractions highly enriched in storage protein were obtained. One fraction (G-1), requiring higher salt concentration for protein solubilization, was dominated by a protein migrating to around M, 55000–60000 when separated under non-reduced condition. After exposure to reducing agent this protein was replaced by two new ones with M, 33000 and 22000 giving evidence of disulfide bonded polypeptides. The other fraction (G-2), was dominated by polypeptides around M, 42000 and low molecular mass polypeptides (<14000).     

Embryology ofCordia sebestena (Boraginaceae)

Sporogeneses and gametogeneses inCordia sebestena are described. Anther wall develops according to the Dicotyledonous type. Pollen grains are three-celled at the time of dehiscence. The occurrence of enlarged, precociously developing, densely cytoplasmic cells toward the proximal end of the anther and between adjacent pollen sacs is a unique feature in this species. The possible functions of these cells are discussed. A placental obturator develops simultaneously with the ovules. The dual origin of parietal tissue (from nucellar epidermis and the archesporial initial) is an unusual feature in this species. Megagametophyte development is monosporic or (occasionally) bisporic. Megaspore tetrads are linear or T-shaped. Double dyads and tetrads are frequently observed.—Maintainance of subfamily status forCordioideae is supported.     

Embryology and relationships of Akania (Akaniaceae)

We present the first extensive study of embryology of Akania , the only genus of Akaniaceae (one of the 15 glucosinolate-producing families). Akania has a distinctive combination of embryological features, which includes bitegmic and crassinucellate ovules; thick, multiplicative and vascularized outer integument; a Polygonum-type embryo sac; albuminous seed; 'exotestal' seed coat with a palisade of columellar, thick-walled cells and a thick and sclerotic mesotesta with the inner tissue aerenchymatous. A comparison of its embryological characteristics with those of some other groups indicates that Akania closely resembles Bretschneideraceae (another glucosinolate-producing family) and Sapindaceae, but it retains some archaic embryological features and is best treated as a separate family in or near Sapindales, as in most modern general classifications. Based on evidence from embryological and other data, Akaniaceae appear to be the sister group of Bretschneideraceae, possibly near to Sapindales. With the data at hand, we cannot fully assess the recent suggestion that Akaniaceae-Bretschneideraceae are a basal group in Capparales.     

新疆阿魏的胚胎学研究

采用常规石蜡制片技术,对新疆阿魏不同发育时期的花和果实进行了显微切片观察.结果表明:新疆阿魏小孢子母细胞的减数分裂为同时型,小孢子四分体为四面体型和十字交叉型,成熟花粉粒为3-细胞型.雌蕊2心皮合生成2室,中轴胎座,每子房室内产生上、下2个胚珠原基,其中,下方的原基正常发育,而上方的原基停止发育并最终解体,因此,每室仅产生一枚发育正常的倒生胚珠,单珠被,薄珠心,胚囊发育为蓼型;珠被绒毡层和珠孔塞发生于大孢子四分体时期,并于四核胚囊时分化完全,八核胚囊时珠被绒毡层细胞径向延长;3个成熟的反足细胞具双核.胚乳发育为核型,细胞壁较厚,细胞排列紧密,可保护胚免受机械损伤及防止胚失水.胚乳细胞中含有大量PAS染色呈正反应的物质,一些胚乳细胞异常生长形成细胞体积大、核及核仁均较大的巨形细胞.胚胎发生为茄型,四细胞原胚为直线形,十六细胞原胚的顶部由2排各4个细胞组成.成熟种子具胚乳.     

Embryology ofEriocaulon setaceum (Eriocaulaceae)

Eriocaulon setaceum can be characterized by: young microsporangium wall with epidermis, endothecium (with fibrous thickenings), and glandular tapetum (uninucleate cells); pollen grains 3-celled, spiraperturate; embryo sac development according to the Polygonum type and with antipodal cyst; endosperm nuclear; embryo small, with incipient differentiation into cotyledonary and epicotylary loci; seed coat mainly from the inner layers of the integuments; pericarp 2-layered and membranous. Embryologically, theEriocaulaceae are nearer to theXyridaceae than to otherFarinosae. Their elevation to the rank of an order,Eriocaulales, therefore appears justified.     

The characterisation of vicilin during seed development in Vicia faba (L.)

Summary Vicilin and legumin were extracted from developing seeds at different stages using the classical method of repeated isoelectric precipitations. The subunits of these two protein fractions were separated by SDS gel electrophoresis, and it was shown that the sub-unit structure of vicilin changed during development whereas that of legumin did not. Thus vicilin is not a single protein.Vicilin was formed prior to legumin during seed development although the rate of synthesis of the latter was faster, so that in the mature seed the ratio of legumin to vicilin was about 4:1 by weight.     

The effect of seed size on the development and yield ofVoandzeia subterranea (L.)Thouars. (Bambara groundnut)

Voandzeia subterranea (L.)Thouars (Bambara groundnut) is a drought and poor soil cultivated legume. The seeds vary both in colour and in size. The seed colour ranges from white, cream, ivory to dark brown red or black. The seed weight varies fromabout 0.15 g to 1.20 g. The effect of seed size on the development and yield of the cream coloured cultivar ofV. subterranea was investigated. The three size class of seeds used in the study are small (seeds weighing less than 0.40 g) medium (seeds weighing from 0.40–0.60g) and large (seeds weighing above 0.60g). The results of the investigation show that the number of leaves, pods and seeds, the leaf area, dry weight of plants and the seeds produced increased significantly with increase in the seed size.     

Metabolism of the seed and endocarp of cherry (Prunus avium L.) during development

In this study some aspects of organic and amino acid metabolism in cherry endocarp and seed were investigated during their development. The abundance and location of a number of enzymes involved in these processes were investigated. These enzymes were aspartate aminotransferase (AspAT; EC:2.6.1.1), glutamine synthetase (GS; EC:6.3.1.2), phosphoenolpyruvate carboxylase (PEPC; EC:4.1.1.31), phosphoenolpyruvate carboxykinase (PEPCK; EC:4.1.1.49), and ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco; EC:4.1.1.39). There was a transient and massive accumulation of vegetative storage proteins in the endocarp. These proteins were remobilised as the endocarp lignified and at the same time that proteins were accumulated in the seed. This raised the possibility that a proportion of imported amino acids were temporarily stored in the endocarp as protein, and that these were later utilised by the seed when it started to accumulate storage proteins. Rubisco was present in the embryo and integuments of the seed although no chlorophyll was present. This is the first time that Rubisco has been detected in non-green seeds. The maximum abundance of Rubisco in the seed coincided with the deposition of seed storage proteins. A possible function for Rubisco in cherry seed is discussed. PEPCK was located in the integuments and appeared when seed storage proteins were being accumulated. In the integuments and embryo AspAT, GS, PEPC and Rubisco also appeared, or greatly increased in abundance, when seed storage proteins were being deposited.     

Embryology and relationships ofGyrocarpus andHernandia (Hernandiaceae)

Two representative genera of Hernandiaceae,Gyrocarpus andHernandia, were investigated embryologically to contribute to a better understanding of their respective evolutionary position. Comparisons with other lauralean families using Chloranthaceae or Annonaceae (as a representative of Magnoliales) as an outgroup of Laurales (if present, plus other related taxa) support a lauraceous affinity for the two genera because of the presence of ramified raphal vascular bundles at the chalaza (a synapomorphy), but do not provide evidence for the separation of Hernandiaceae from Lauraceae.Hernandia rather shares with Lauraceae two apomorphies (i.e., the seed pachychalazy and the ruminate seed) which may be homoplasies judged from results of cladistic and molecular studies published elsewhere.Hernandia is greatly divergent from an ancestral line common withGyrocarpus and is even diversified within the genus. Based on evidence from embryology as well as from other sources, it seems best to accept two separate subfamilies in Hernandiaceae as usually have been accepted: one is a derived subfamily Hernandioideae, and the other a less specialized Gyrocarpoideae.     

中国特有河口异叶苣苔（苦苣苔科）胚胎学研究

对河口异叶苣苔的胚胎学观察旨在为该属的系统学研究提供参考。该种的花药药壁由表皮、药室内壁、中岐和绒层４层细胞组成。２－３－核细胞在绒毡层频繁出现。胚珠属倒生,单珠被和薄珠心。胚囊发育属蓼型。该种胚囊发中的双大孢子母细胞现象,分别为并列和前后排列型。前者发育至双并列四分体,后者发育到呈棱形的４个大孢子。胚乳的发育属细胞型。并在合点端和珠也端分别具有吸器。珠孔吸器发育早期为单核、２－细胞、后期为两核、２－细胞或单核、４－细胞,有时为多细胞,并在发育过程中向外伸长形成外珠孔。合点吸器为两核。由于合点吸器和珠孔吸器的活动,位于珠被最外层细胞的珠和被绒毡层之间的２－３层细胞逐渐解体和被吸收,胚的发生和发育属柳叶菜型,在胚的发育过程中,胚乳几乎被吸收耗尽,仅利下一层胚乳细胞紧贴内种皮,成熟种子的种皮由珠被最外层细胞和珠被绒毡层发育而来,本文对河口异叶苣苔的胚胎发育过程员苦苣苔科其它类群进行了广泛的比较和讨论。     

Embryogenesis and seed development in Sinomanglietia glauca (Magnoliaceae)

The development of the floral bud, especially the ovule and seed coat, of Sinomanglietia glauca was observed. Floral buds were covered by eight to nine hypsophyll pieces. The hypsophyll nearest the tepal was closed completely and characterized by two arrays of densely stained cells with dense cytoplasm, which split longitudinally at flowering. The perianth consisted of 16 tepals arranged in three whorls. The gynoecium was composed of numerous apocarpous carpels; the ovule was anatropous with two integuments. Embryogenesis was of the Polygonum type, and the endosperm was nuclear. The inner integument degenerated during seed development. The seed of S. glauca had an endotestal seed coat comprised of a sclerotic layer derived from the inner adaxial epidermis of the outer integument and a sarcotesta derived mainly from the middle cells between the inner and outer epidermis of the outer integument. The embryo developed normally, so embryogenesis is not the cause of difficult regeneration.