Patterns of floral development in Agalinis and allies (Scrophulariaceae). I. Floral development of Agalinis fasciculata and A. tenuifolia

1987 ◽  
Vol 65 (11) ◽  
pp. 2255-2262 ◽  
Author(s):  
Christine M. Kampny ◽  
Judith M. Canne-Hilliker
Keyword(s):  
Floral Development ◽  
Floral Character ◽  
Sequence Of Events ◽  
Stamen Primordia ◽  
Lateral Posterior ◽  
Floral Bud ◽  
Two Sides

The sequence of events and morphology of structures were similar during early floral development of Agalinis tenuifolia and A. fasciculata. The lateral-posterior calyx primordia were initiated first, followed by the middle-posterior primordium, and lastly by the two anterior primordia. The corolla primordia arose in an anterior to posterior succession, then the four stamen primordia were initiated simultaneously. Later the gynoecium originated as an oval-shaped ridge. Two depressions within it became locules, and the two sides of the cleaved ridge separating them met and formed a septum. A placenta formed in each locule and numerous ovules were initiated on it. Zygomorphy was apparent in the calyx, corolla, and androecium during the primordial stage. Organogenesis in the calyx was rapid so that the calyx lobes and tube were well formed before organogenesis of other floral parts. Except for those of the calyx, floral character states distinctive for each species were manifested late in development of the floral bud.

L'androcée centripète d’Ochna atropurpurea

1978 ◽  
Vol 56 (20) ◽  
pp. 2500-2511 ◽  
Author(s):  
Fernand Pauzé ◽  
Rolf Sattler
Keyword(s):  
Floral Development ◽  
Fundamental Importance ◽  
Reliable Criterion ◽  
Early Stages ◽  
Stamen Primordia ◽  
Family Level ◽  
Definite Pattern ◽  
Phylogenetic Lineages ◽  
Floral Bud

After the inception of usually five sepals and five petals, five primary androecial primordia are initiated as broad bulges in alternation with the narrow petal primordia. On each of these primary androecial primordia, usually seven stamen primordia (i.e., secondary androecial primordia) are formed centripetally in a definite pattern. The fasciculate pattern of the androecium is noticeable only in very early stages of floral development since the stamen primordia of adjacent primary androecial primordia approach each other as closely as the stamen primordia of the same primary androecial primordium. Furthermore, the number and arrangement of the stamen primordia on the primary androecial primordia may vary even within the same floral bud. The total number of stamens per floral bud varied from 26 to 43, while the number of petals varied from 4 to 6. Some of the stamen primordia, especially among the inner ones, sometimes develop into filament-like staminodia. The findings support the view that the Dilleniidae cannot be generally characterized by a centrifugal androecium. The sequence of stamen inception is not necessarily of such fundamental importance that it is a reliable criterion for the reconstitution of major phylogenetic lineages at or above the rank of families. Shifts from a centrifugal to a centripetal androecium or vice versa may have occurred during the evolution of taxa at the ordinal (or even family) level. [Translated by the journal]

scholarly journals Ethylene and 1-methylcyclopropene action over senescence of nasturtium flowers

2015 ◽  
Vol 33 (4) ◽  
pp. 453-458 ◽  
Author(s):  
Tania P Silva ◽  
Fernando L Finger
Keyword(s):  
Floral Development ◽  
Development Stage ◽  
Flower Senescence ◽  
Premature Senescence ◽  
Flower Opening ◽  
Development Stages ◽  
Post Harvest ◽  
The Third ◽  
Exogenous Ethylene ◽  
Floral Bud

ABSTRACT: This work describes ethylene and 1-methylcyclopropene (1-MCP) action on post-harvest shelf life of four development stages of nasturtium flowers. To reach this goal, we carried out three experiments. In the first and second experiments, we studied five ethylene (0; 0.1; 1; 10; 100 and 1000 μL/L) and three 1-MCP concentrations (0.25; 0.5 and 0.75 μL/L), respectively. In the third experiment, 1-MCP was followed by combined with ethylene (only 1-MCP; only ethylene; and 24 hours of exposure to 0.75 μL/L 1-MCP followed by 24 hours of exposure to 100 μL/L ethylene). All experiments had two control treatments, one keeping non-exposed flowers inside and another outside exposure chambers. Experiments were set in factorial design, in complete blocks at random, with four 10-flower replications each. Flower senescence was determined by a pre-established visual scale and by observing floral bud development. Ethylene dose above 10 μL/L induced flower wilting and premature senescence from the second floral development stage. Furthermore, higher concentrations of exogenous ethylene promoted irregular flower opening and/or morphological abnormalities in opened flowers. 1-MCP effectively extended post-harvest longevity of nasturtium flowers, independent of the concentration and even in the presence of exogenous ethylene.

Floral development of Potamogeton densus

1973 ◽  
Vol 51 (3) ◽  
pp. 647-656 ◽  
Author(s):  
U. Posluszny ◽  
R. Sattler
Keyword(s):  
Floral Development ◽  
The Other ◽  
Floral Meristem ◽  
Developmental Sequence ◽  
Initial Activity ◽  
The Third ◽  
Stamen Primordia ◽  
Procambial Strand ◽  
Inflorescence Axis ◽  
Rates Of Growth

The floral appendages of Potamogeton densus are initiated in an acropetal sequence. The first primordia to be seen externally are those of the lateral tepals, though sectioning young floral buds (longitudinally, parallel to the inflorescence axis) reveals initial activity in the region of the lower median (abaxial) tepal and stamen at a time when the floral meristem is not yet clearly demarcated. The lateral (transversal) stamens are initiated simultaneously and unlike the median stamens each arises as two separate primordia. The upper median (adaxial) tepal and stamen develop late in relation to the other floral appendages, and in some specimens are completely absent. Rates of growth of the primordia vary greatly. Though the lower median tepal and stamen are initiated first, they grow slowly up to gynoecial inception, while the upper median tepal appears late in the developmental sequence but grows rapidly, soon overtaking the other tepal primordia. The four gynoecial primordia arise almost simultaneously, although variation in their sequence of inception occurs. The two-layered tunica of the floral apices gives rise to all floral appendages through periclinal divisions in the second layer. The third layer (corpus) is involved as well in the initiation of the stamen primordia. Procambial strands develop acropetally, lagging behind primordial initiation. The lateral stamens though initiating as two primordia each form a single, central procambial strand, which differentiates after growth between the two primordia of the thecae has occurred. A great amount of deviation from the normal tetramerous flower is found, including completely trimerous flowers, trimerous gynoecia with tetramerous perianth and androecium, and organs differentiating partially as tepals and partially as stamens.

Floral development of two species of Stylidium (Stylidiaceae) and some remarks on the systematic position of the family Stylidiaceae

1992 ◽  
Vol 70 (2) ◽  
pp. 258-271 ◽  
Author(s):  
Claudia Erbar
Keyword(s):  
Key Words ◽  
Floral Development ◽  
Floral Biology ◽  
Systematic Position ◽  
Inferior Ovary ◽  
Stamen Primordia ◽  
Floral Apex ◽  
The Family ◽  
Transversal Plane

The early floral development of Stylidium adnatum and Stylidium graminifolium is characterized by an initial circular primordium whose areas in the transversal plane of the floral primordium show enhanced growth. The spiral inception of the five sepals starts before the differentiation of the initial circular primordium into two stamen primordia in transversal position (in relation to the floral diagram) and the corolla ring primordium below the stamen primordia. Then five petal primordia, which alternate with the sepals, arise on the corolla ring primordium (early sympetaly). Peculiar to the flowers of Stylidiaceae is the column that bears at its top both stigma and anthers. Probably this column should be interpreted as a receptacular tube. No distinct carpel primordia have been observed. The inferior ovary results from intercalary growth in the peripheral parts of the receptacle below the calyx, corolla, and stamen primordia. The residual floral apex gives rise to a transversal septum, by which the ovary becomes bilocular. None of the morphological, palynological, and embryological characters discussed contradicts a position of the Stylidiaceae near the Campanulales, and several of these characters support this position. Key words: Stylidiaceae, Campanulales, floral development, systematic position, floral biology.

The vegetative and floral development of the hybrid grape cultivar ‘Ventura’

1986 ◽  
Vol 64 (8) ◽  
pp. 1620-1631 ◽  
Author(s):  
Usher Posluszny ◽  
Jean M. Gerrath
Keyword(s):  
Fourth Order ◽  
Floral Development ◽  
Upper Arm ◽  
Grape Cultivar ◽  
Stamen Primordia ◽  
Short Style

The vegetative and floral development of the hybrid grape cultivar ‘Ventura’ was studied. A tendril forms opposite the last-formed leaf on the shoot but is slightly delayed in its initiation. Six nodes and 10 primordia complete one leaf–tendril initiation cycle. The inflorescence develops at the same site and is initially indistinguishable from the tendril. Inflorescence primordia are initiated on the upper arm, first opposite each other in a decussate arrangement and then apparently spirally. Each inflorescence primordium may subsequently initiate two lateral primordia, which become subtended by bracts. These in turn may repeat the pattern so that ultimately third- or fourth-order cysmose inflorescence branches may be produced. During floral development the calyx is initiated at first as three primordia, followed by a ring, which ultimately develops five lobes. The five corolla primordia alternate with the sepals. The five stamen primordia are initiated opposite the petals. The gynoecium initiates as five primordia, which later become a ring. Two septae are initiated opposite each other on the inner flank of the ring, forming the two-loculed ovary. Each septum forms a placenta, giving rise to two ovules. The upper portion of the gynoecial ring grows up over the ovules and forms the short style and discoid stigma.

Floral development in Melaleuca and Callistemon (Myrtaceae)

1998 ◽  
Vol 11 (6) ◽  
pp. 689 ◽  
Author(s):  
D. A. Orlovich ◽  
A. N. Drinnan ◽  
P. Y. Ladiges
Keyword(s):  
Floral Development ◽  
Flower Bud ◽  
Variable Expression ◽  
Total Absence ◽  
Stamen Primordia ◽  
Intermediate Morphology ◽  
Floral Apex

Floral development of seven species of Melaleuca and four species of Callistemon is compared. The multistaminate fascicles of Melaleuca develop from stamen primordia initiated on antepetalous pre-staminal bulges (PSBs); the resultant bundles of stamens become separated by hypanthial expansion as the flower bud enlarges. In most species of Callistemon examined the stamen primordia are initiated directly on the floral apex, and the stamens are distributed evenly around the hypanthium at anthesis. The possession of large and prominent PSBs, and thus stamen fascicles, is a feature of most species of Melaleuca and their total absence is a feature of most species of Callistemon; however, there is a continuum between these two extremes. Several taxa of both genera exhibit intermediate morphology. In C. glaucus (Bonpl.) Sweet, small but distinct PSBs develop, which influence antepetalous stamen groups that remain contiguous at anthesis. This also occurred in M. leucadendra (L.) L. This variable expression of PSBs is the result of differences in the timing of stamen initiation. Other variable features are determined by the space available for primordium initiation and the patterns of growth and expansion of the developing flower.

An updated interpretation of the androecium of the Fumariaceae

1992 ◽  
Vol 70 (9) ◽  
pp. 1765-1776 ◽  
Author(s):  
L. P. Ronse Decraene ◽  
E. F. Smets
Keyword(s):  
Key Words ◽  
Floral Development ◽  
Flower Bud ◽  
Stamen Primordia ◽  
Outer Whorl ◽  
Spatial Median ◽  
Median Position

A study of the floral development of Dicentra formosa, Corydalis lutea, and Hypecoum procumbens was carried out to better understand the nature of the androecium in Fumariaceae. Sepals emerge successively in a median position and are followed by two alternating pairs of petals. Four stamen primordia are formed in a diagonal position. They are promptly followed by two lateral, slightly externally inserted primordia. In Dicentra and Corydalis the stamens arise on two crescent-shaped protuberances. In Hypecoum, four diagonal androecial primordia fuse into two median staminal complexes. The gynoecium emerges as a girdling primordium with four growth centers. Different interpretations of the androecium are discussed. It is demonstrated that the androecium in the Fumariaceae consists basically of two whorls: an outer whorl of four alternipetalous stamens and an inner whorl of two lateral stamens superposed to the outer petals. The monothecal nature of the alternipetalous stamens and the fusion of the stamens in two triplets is probably caused by a spatial median compression of the flower bud. The androecium of Hypecoum is the result of interprimordial growth between the pairs of monothecal stamens, and the androecium of Pteridophyllum arises through the loss of the two lateral stamens superposed to the outer petals. Key words: Fumariaceae, floral development, androecium, stamen whorls.

scholarly journals Rootstock Effects on the Flowering of `Delicious' Apple. I. Bud Development

1995 ◽  
Vol 120 (6) ◽  
pp. 1010-1017 ◽  
Author(s):  
Peter M Hirst ◽  
David C Ferree
Keyword(s):  
Floral Development ◽  
Dry Weight ◽  
Growing Season ◽  
Flower Formation ◽  
Full Bloom ◽  
Floral Buds ◽  
One Year ◽  
Floral Bud ◽  
Leaf Dry Weight

Floral development was studied in buds of `Starkspur Supreme Delicious' apple trees growing on B.9, M.26 EMLA, M.7 EMLA, P.18, and seedling rootstocks. In each of 3 years, buds were sampled from the previous years growth at intervals throughout the growing season and dissected to determine whether the apex was domed, indicating the start of floral development. Number of bud scales and true leaves increased during the early part of the growing season, but remained fairly constant beyond 70 days after full bloom. The type of rootstock did not affect the number of bud scales or transition leaves, and effects on true leaf numbers were small and inconsistent. Final bract number per floral bud was similarly unaffected by rootstock. The proportion of buds in which flowers were formed was influenced by rootstock in only one year of the study, which was characterized by high temperatures and low rainfall over the period of flower formation. Bracts were observed only in floral buds, and became visible after doming of bud apices had occurred. Flowers were formed during the first 20 days in August, regardless of rootstock or year. The appendage number of vegetative buds was constant from 70 days after full bloom until the end of the growing season, but the number of appendages in floral buds increased due to the continued production of bracts. The critical bud appendage number for `Starkspur Supreme Delicious' before flower formation was 20, and was stable among rootstocks and years. Buds with diameters above 3.1 mm were generally floral, but on this basis only 65% of buds could be correctly classified. Spur leaf number, spur leaf area, and spur leaf dry weight were not good predictors of floral formation within the spur bud.

Floral development of Ruppia maritima var. maritima

1974 ◽  
Vol 52 (7) ◽  
pp. 1607-1612 ◽  
Author(s):  
U. Posluszny ◽  
R. Sattler
Keyword(s):  
Floral Development ◽  
Early Ontogeny ◽  
Main Axis ◽  
Ruppia Maritima ◽  
Procambial Strand ◽  
Inflorescence Axis ◽  
Floral Apex ◽  
Median Position ◽  
Floral Bud

A hyaline, unvascularized sheath envelops a portion of the inflorescence near maturity. Though resembling an appendage of the main axis, in early ontogeny it develops as a prophyll of the renewal growth apex below the inflorescence. Two flowers develop on the inflorescence axis, subopposite each other. Fertile appendages are initiated in an acropetal sequence on each floral bud. The first to form, in the median position, are the two stamens, the lower preceding the upper. Each stamen develops two bisporangiate thecae separated by a broad connective. A dorsiventral outgrowth is initiated slightly abaxially near the tip of the connective at the stage of theca differentiation. This outgrowth appears to be homologous with a similar outgrowth in Potamogeton densus, but not with the sterile appendages of the Potamogeton flower which, by some authors, have incorrectly been interpreted as connective outgrowths. Each carpel arises as a radial primordium which becomes peltate after its inception. One ovule is initiated at the adaxial portion (Querzone). The stigma becomes broad and flat, lobing at its margins. A slight outgrowth develops at the abaxial wall of the carpel. The floral apex has a two-layered tunica. The primordia of the stamens, carpels, and ovules arise by periclinal divisions in the second layer. Procambial development is acropetal following closely primordial inception. Each appendage, including the ovule, receives one procambial strand. The outgrowths of the connective and the carpel lack procambium.

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.

Sign in / Sign up

Export Citation Format

Share Document