Developmental morphology of the flower of Anaphyllopsis americana and its relevance to our understanding of basal Araceae

Botany ◽  
2008 ◽  
Vol 86 (12) ◽  
pp. 1467-1473 ◽  
Author(s):  
Denis Barabé ◽  
Christian Lacroix
Keyword(s):  
Phylogenetic Relationships ◽  
Floral Development ◽  
Early Stage ◽  
Anther Wall ◽  
Structural Constraints ◽  
Developmental Morphology ◽  
Circular Shape ◽  
Molecular Studies ◽  
Floral Primordia ◽  
Mode Of Development

The inflorescence of Anaphyllopsis americana (Engler) A. Hay consists of more than 100 flowers arranged in recognizable spirals. Each flower has four broad tepals enclosing four stamens that are not visible prior to anthesis. The unilocular ovary contains one ovule and bears a discoid stigma. The floral primordia are first initiated on the upper portion of the inflorescence. At an early stage during their development, the floral primordia have a circular shape. Two lateral tepals are initiated nearly simultaneously followed by two median tepals. After their initiation, each stamen is associated with a tepal of the same radius; the two lateral stamens are initiated first, directly opposite to the lateral tepals. The unilocular nature of the ovary is clearly visible during the early stages of development of the gynoecium. At dehiscence, anther wall raphides are present in anther locules and are mixed with pollen. The mode of floral development observed in Anaphyllopsis is similar to that reported for Anthurium jenmanii Engl. However, this similarity in mode of development may be linked to structural constraints rather than phylogenetic relationships. The presence of a few pentamerous flowers in the inflorescence of Anaphyllopsis suggests a possible relationship with Dracontium . This would be in accordance with recent molecular studies showing that Anaphyllopsis and Dracontium are closely related.

Some Effects of Temperature and Light on Floral Initiation and Development in Acacia pycnantha

1985 ◽  
Vol 12 (2) ◽  
pp. 109 ◽  
Author(s):  
M Sedgley
Keyword(s):  
Light Intensity ◽  
Floral Development ◽  
Early Stage ◽  
The Other ◽  
Floral Initiation ◽  
Ambient Conditions ◽  
Low Light ◽  
Floral Primordia ◽  
Effects Of Temperature ◽  
Normal Light

Floral initiation and development in Acacia pycnantha were studied under three environments. Two had ambient southern Australian temperatures of warm summer (mean max. 32°C, mean min. 16°C) and cool winter (mean max. 19°C, mean min. 8°C), one with full sunlight (outside) and the other with 30% light intensity (shadehouse). The other environment (glasshouse) had slightly lower than normal light intensity and a relatively constant year round temperature of mean 28°C maximum and 16°C minimum. Plants were scored for microscopic and macroscopic evidence of floral initiation and development. Floral primordia were initiated all year round under all environments. Floral development proceeded normally under ambient conditions of temperature and light, and anthesis occurred between August and October. Under low light intensity, floral development did not progress beyond a very early stage and macroscopically visible racemes were rare. Under the constant temperatures, floral development proceeded normally up to the stage of microsporogenesis and megasporogenesis. Meiosis did not occur and inflorescence buds ceased growth and were shed from the plant. Plants were transferred between the outside and glasshouse conditions in June, at around the stage of meiosis. Those transferred from outside to the glasshouse did not flower whereas some of those transferred from the glasshouse to outside flowered, but later and for a shorter period than plants maintained outside throughout. It appears that a 70% reduction in sunlight inhibits floral development at an early stage and that temperatures of approximately mean maximum 19°C and minimum 8°C are required for meiosis in Acacia pycnantha.

Developmental morphology of the flower of Anthurium jenmanii: a new element in our understanding of basal Araceae

Botany ◽  
2008 ◽  
Vol 86 (1) ◽  
pp. 45-52 ◽  
Author(s):  
Denis Barabé ◽  
Christian Lacroix
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Calcium Oxalate ◽  
Floral Development ◽  
Developmental Morphology ◽  
Calcium Oxalate Crystals ◽  
Stages Of Development ◽  
Early Stages ◽  
Floral Primordia ◽  
Scanning Electron

The early stages of development of the inflorescence of Anthurium jenmanii Engl. were examined using scanning electron microscopy. The inflorescence of A. jenmanii consists of more than 100 flowers arranged in recognizable spirals. Each flower has four broad tepals enclosing four stamens that are not visible prior to anthesis. The gynoecium consists of two carpels. The floral primordia are first initiated on the lower portion of the inflorescence, they then increase in size and appear as transversely extended bulges. The two lateral tepals are the first organs to be initiated, followed shortly thereafter by the two median tepals. The two lateral stamens are initiated first, directly opposite the lateral tepals, and are followed by two median stamens initiated directly opposite the median tepals. A two-lobed stigma is clearly visible during the early stages of development of the gynoecium. On some of the young inflorescences, all floral parts were covered by extracellular calcium oxalate crystals. The release of these prismatic crystals occurs before the stamens and petals have reached maturity. The mode of floral development observed in Anthurium has similarities with that reported for Gymnostachys . However, contrary to Gymnostachys, the development of the flower of A. jenmanii is not unidirectional.

scholarly journals Mitochondrial phylogeography of baboons (Papiospp.) – Indication for introgressive hybridization?

2009 ◽  
Vol 9 (1) ◽  
Author(s):  
Dietmar Zinner ◽  
Linn F Groeneveld ◽  
Christina Keller ◽  
Christian Roos
Keyword(s):  
Phylogenetic Relationships ◽  
Evolutionary History ◽  
Introgressive Hybridization ◽  
Distinct Species ◽  
Eastern Africa ◽  
East African ◽  
Hamadryas Baboons ◽  
Olive Baboons ◽  
Initial Separation ◽  
Molecular Studies

Abstract Background Baboons of the genus Papio are distributed over wide ranges of Africa and even colonized parts of the Arabian Peninsula. Traditionally, five phenotypically distinct species are recognized, but recent molecular studies were not able to resolve their phylogenetic relationships. Moreover, these studies revealed para- and polyphyletic (hereafter paraphyletic) mitochondrial clades for baboons from eastern Africa, and it was hypothesized that introgressive hybridization might have contributed substantially to their evolutionary history. To further elucidate the phylogenetic relationships among baboons, we extended earlier studies by analysing the complete mitochondrial cytochrome b gene and the 'Brown region' from 67 specimens collected at 53 sites, which represent all species and which cover most of the baboons' range. Results Based on phylogenetic tree reconstructions seven well supported major haplogroups were detected, which reflect geographic populations and discordance between mitochondrial phylogeny and baboon morphology. Our divergence age estimates indicate an initial separation into southern and northern baboon clades 2.09 (1.54–2.71) million years ago (mya). We found deep divergences between haplogroups within several species (~2 mya, northern and southern yellow baboons, western and eastern olive baboons and northern and southern chacma baboons), but also recent divergence ages among species (< 0.7 mya, yellow, olive and hamadryas baboons in eastern Africa). Conclusion Our study confirms earlier findings for eastern Africa, but shows that baboon species from other parts of the continent are also mitochondrially paraphyletic. The phylogenetic patterns suggest a complex evolutionary history with multiple phases of isolation and reconnection of populations. Most likely all these biogeographic events were triggered by multiple cycles of expansion and retreat of savannah biomes during Pleistocene glacial and inter-glacial periods. During contact phases of populations reticulate events (i.e. introgressive hybridization) were highly likely, similar to ongoing hybridization, which is observed between East African baboon populations. Defining the extent of the introgressive hybridization will require further molecular studies that incorporate additional sampling sites and nuclear loci.

Phylogenetic relationships among Halymenia (Halymeniaceae, Rhodophyta) species on the Brazilian coast with description of Halymenia cearensis sp. nov.

Phytotaxa ◽  
2016 ◽  
Vol 280 (3) ◽  
pp. 241 ◽  
Author(s):  
CAROLINA ANGÉLICA ARAÚJO DE AZEVEDO ◽  
VALÉRIA CASSANO ◽  
MARIANA CABRAL OLIVEIRA
Keyword(s):  
Species Diversity ◽  
Phylogenetic Relationships ◽  
Brazilian Coast ◽  
Molecular Tools ◽  
Ecological Data ◽  
Cortical Cells ◽  
Broad Base ◽  
Molecular Studies ◽  
Marine Flora ◽  
Inner Cortex

Phylogenetic relationships and species diversity within the genus Halymenia along the Brazilian coast were investigated through molecular and morphological analyses. Molecular studies included UPA, COI-5P and rbcL markers. A total of five Halymenia species were found: Halymenia cearensis sp. nov., H. ignifera, H. pinnatifida, H. silviae and H. cf. mirabilis. Halymenia cearensis was molecularly distinct from all other Halymenia species included in this study and is morphologically characterized by: cleft, lobate, oblong or obovate blades with broad base; apex irregular in shape; surface with bullations, rugosities, spiny and globular papillae irregularly distributed; abundant and conspicuous ganglionic cells throughout; blades up to 800 µm thick at base; outer cortical cells ellipsoidal or ovoid in shape, higher than broad; and inner cortex cells 4–25 µm in width. Our phylogeny demonstrated that entities attributed to H. floridana and H. elongata occurring in Brazil correspond to two distinct genera, which was also supported by morphological and ecological data. The use of molecular tools was crucial to provide a better understanding of the diversity of Brazilian marine flora.

The development, penetrance, and seed vigour of multi-ovary wheat and its application in hybrid breeding

2019 ◽  
Vol 70 (9) ◽  
pp. 781 ◽  
Author(s):  
Jialin Guo ◽  
Gaisheng Zhang ◽  
Yulong Song ◽  
Shoucai Ma ◽  
Na Niu ◽  
...  
Keyword(s):  
Floral Development ◽  
Theoretical Foundation ◽  
Developmental Process ◽  
Early Stage ◽  
Wheat Breeding ◽  
Hybrid Breeding ◽  
High Yield ◽  
Practical Application ◽  
Seed Vigour ◽  
Germination Ability

Multi-ovary wheat is a unique variety of wheat that has one to three pistils and three stamens, and can stably set one to three grains in each floret. By observing the developmental process of additional pistils, we found that the additional pistil was derived from a protrusion generated at the base of the main pistil, between the frontal stamen and lateral stamen. The additional pistil’s development was greatly delayed compared with the main pistil at an early stage. However, after the awn exposed stage, it developed very rapidly to a mature pistil within the maturity time of the main pistil. Generally, the grains originating from additional pistils were smaller than the grains from the main pistil. By studying the penetrance and germination conditions of multi-ovary wheat, we found that no matter which ovary the grains originated from, they had the same penetrance. However, the germination ability of grains generated from the main pistil was significantly higher than that of grains from additional pistils. Our results showed that multi-ovary wheat was an excellent variety, not only for studying the mechanisms of the multi-ovary trait and floral development in wheat, but also for improving the propagation coefficient and promoting the progress of wheat breeding. This paper lays a theoretical foundation for the practical application of multi-ovary trait in hybrid wheat; our results could be implemented in fostering future breeding activities focussed on the development of high yield wheat cultivars.

Morphological reassessment and molecular assessment of Sargassum (Fucales: Phaeophyceae) species from the Gulf of California, Mexico

Phytotaxa ◽  
2014 ◽  
Vol 183 (4) ◽  
pp. 201 ◽  
Author(s):  
GABRIELA ANDRADE-SORCIA ◽  
RAFAEL RIOSMENA-RODRIGUEZ ◽  
RAQUEL MUÑIZ-SALAZAR ◽  
JUAN MANUEL LÓPEZ-VIVAS ◽  
GA HUN BOO ◽  
...  
Keyword(s):  
Phylogenetic Analysis ◽  
Phylogenetic Relationships ◽  
Brown Algae ◽  
Gulf Of California ◽  
Phylogenetic Analyses ◽  
The Pacific ◽  
Pacific Side ◽  
Molecular Studies ◽  
Molecular Assessment ◽  
The Individual

Systematic molecular studies have not been performed on ecologically important brown algae (Sargassum) in the Gulf of California, Mexico, where 42 specific and infraspecific names have been recorded within this genus. We conducted phylogenetic analyses of nuclear ribosomal ITS and mitochondrial cox1 and cox3 sequences, along with detailed morphological observations of Sargassum collected in the Gulf of California. We confirmed the presence of six species, five previously described—S. herporhizum, S. horridum, S. johnstonii, S. lapazeanum, and S. sinicola, as well as the newly described Sargassum ulixei sp. nov. which is characterized by terete primary axes arising from the stipe, lanceolate to elliptical sessile ecostate blades with smooth margins, cryptostomata, ellipsoidal vesicles with a short mucron, and cylindrical to ellipsoidal receptacles. The individual analyses and subsequent phylogenetic analysis recognized two groups previously described by Dawson, one as Sargassum and other as Horridum. Our studies suggest that the Gulf of California is a region with endemic Sargassum species, and is clearly distinguished from the Pacific side of Baja California, where recently introduced species are common. Based on phylogenetic relationships, we propose two geographical origins for the Sargassum from the Gulf of California: a first group originating from the proto-Gulf, related to species from the northern hemisphere (including five species); and a second group, containing S. sinicola, introduced when the southern end opened at a later stage. 

Floral development of Maidenia rubra Rendle, (Hydrocharitaceae)

1983 ◽  
Vol 31 (6) ◽  
pp. 585 ◽  
Author(s):  
CA McConchie
Keyword(s):  
Floral Development ◽  
Floral Morphology ◽  
Male Flower ◽  
Pollen Grains ◽  
Anther Wall ◽  
Male And Female ◽  
The Third ◽  
Male Inflorescence ◽  
Single Flower

Floral development of Maidenia rubra was followed from initiation to maturity. Plants are dioecious. Both male and female inflorescences develop from complexes initiated subapically. Complexes have three meristematic components that include two inflorescence initials flanking a central primordium; these form sequentially in the axil of the preceding initial. The third component also produces an inflorescence and branches sympodially to form further floral initials that have a spiral arrangement. The female inflorescences produce a single flower only with an inferior, unilocular ovary and three sepals, staminodes and bifid stigma. In the locule, numerous bitegmic ovules, borne panetally, are produced. A male inflorescence produces hundreds of small flowers that are released and float to the surface individually. Each male flower has three sepals, a staminode and two stamens, each anther consisting of three locules with eight pollen grains. Prior to maturation, the anther wall breaks down leaving a membraneous layer that assists in binding the octad of pollen grains together. Both male and female inflorescences are enclosed in a pair of fused bracts. The floral morphology is compared with other closely related genera in the Hydrocharitaceae and the unique features are assessed.

Systematics and molecular phylogenetics of Asian snail-eating snakes (Pareatidae)

Zootaxa ◽  
2011 ◽  
Vol 3001 (1) ◽  
pp. 57 ◽  
Author(s):  
YUHONG GUO ◽  
YUNKE WU ◽  
SHUNPING HE ◽  
HAITAO Shi ◽  
ERMI ZHAO
Keyword(s):  
Molecular Phylogeny ◽  
Dna Sequences ◽  
Phylogenetic Relationships ◽  
Molecular Phylogenetics ◽  
Nuclear Gene ◽  
Morphological Characters ◽  
Cyt B ◽  
Ongoing Controversy ◽  
Distinct Genus ◽  
Molecular Studies

The taxonomy of the Asian snail-eating snakes (Pareatidae) is an ongoing controversy, partly because morphological characters do not yield consistent results across studies. We infer phylogenetic relationships within Pareatidae using ~ 2 kilobases of DNA sequences including two mitochondrial (cyt b and ND4) and one nuclear gene (c-mos). Results reveal four major lineages: Aplopeltura, Asthenodipsas, a clade formed by Pareas carinatus and P. nuchalis, and a clade comprising all other species of Pareas sampled in this study. Our data do not have enough signal to either support or reject a monophyletic Pareas. However, large molecular divergence (16.5%) is observed between the two major clades of Pareas, a level that is comparable to that between Pareas and Aplopeltura. Scale characters also suggest that P. carinatus and P. nuchalis are distinct from congeners, and future morphological and/or molecular studies might assess whether a distinct genus should be recognized. The molecular phylogeny further suggests a distant relationship between P. chinensis and P. formosensis and supports the validity of the former species.

Are Synthyris and Besseya closely related to Wulfenia (Scrophulariaceae – Veroniceae)? Evidence from floral development

1995 ◽  
Vol 73 (10) ◽  
pp. 1662-1675 ◽  
Author(s):  
Christine M. Kampny
Keyword(s):  
Principal Components ◽  
Phylogenetic Relationships ◽  
Quantitative Methods ◽  
Floral Development ◽  
Corolla Tube ◽  
Seed Morphology ◽  
Corolla Lobe ◽  
Development Patterns ◽  
Components Analysis ◽  
Besseya Alpina

Within the tribe Veroniceae (Scrophulariaceae), Synthyris and Besseya have been grouped at times with Wulfenia, because of their rosette habit, and with cauline-leaved Veronica, because of similarities of pollen and seed morphology. Floral development patterns of Synthyris reniformis, Besseya alpina, and Wulfenia carinthiaca were studied with quantitative methods to contribute additional evidence towards resolving the phylogenetic relationships of those genera. For each species, 19 flower organ measurements were taken on each of 50 buds from all stages of development. Compared to the fast early corolla development observed in most Scrophulariaceae, all species examined shared a delay in early corolla tube growth which was less extreme than that observed in Veronica. A strong delay in early corolla lobe growth was shared only between Veronica, Synthyris, and Besseya. This derived attribute is a possible synapomorphy supporting hypotheses of monophyly of those genera. Summarizing all measurements with multigroup principal components analysis showed that the overall floral allometries of Wulfenia have more similarity with those of Digitalis than with Veronica and relatives; this concurs with evidence from vegetative and reproductive morphology. Key words: floral development, allometry, phylogeny.

Photoperiod and floral-bud development in Caryopteris × clandonensis

1978 ◽  
Vol 56 (16) ◽  
pp. 1844-1851
Author(s):  
David B. Layzell ◽  
Roger F. Horton
Keyword(s):  
Floral Development ◽  
Anther Wall ◽  
Stages Of Development ◽  
Bud Development ◽  
Early Stages ◽  
Floral Bud ◽  
Short Days

Floral development in Caryopteris × clandonensis A. Simmonds (C. incana (Houtt.) Miq. × C. mongholica Bunge) from cyme initiation through to anthesis is described, with emphasis on the development of the anthers. The later stages of development and anthesis are completed only on mature plants under short days (SD, 8 h light per day). Under long days (LD, 20 h light per day) senescence occurs in the early stages of anther wall differentiation.

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